pete roper

Surely nobody actually uses a torque wrench on axle nuts???? Unless of course they have weedy spacers when I suppose there is an un-necessary need. Good lord, it's a wheel spindle, you do it up until just before you fart! All it's got to do is clamp a few bits together and not fall out, how hard is that. I believe the V11's even have a nylock type nut to stop it falling to bits of it's own accord but honestly If you can't work out how tight an axle nut should be then I suggest that you shouldn't be allowed out in public without a leash, and you certainly shouldn't be allowed to ride a motorbike, never mind work on it Pete

Mate, I never said that the problem wasn't caused, (at least in part.) by the incorrectly fitted cap, simply that in a situation like this where a young engine has gone tits-up in a major way I'd be looking a lot deeper than just finding one problem and fixing that and then pronouncing it cured! I currently have a Mk IV Lemans in my shop, it's a mates bike and I know how it has been cosseted all it's life. The thing is that it lost oil pressure and the deeper I've gone into it the odder it looks. I've found a couple of things that may well be the source of it's problems but I put the proposition to him that it would be better to go through it and zero time it. I said wait 24hours to think about it but he got staright back and said 'Go for it'. This to me is the wise decision because it means we can check *everything* rather than just fixing the superficial shit! All I was suggesting was that you get whoever is doing the rebuild to go through everything with a fine tooth comb as it goes back together. I'd do this as a matter of course but if your dealer is NOT a commited Guzzi enthusiast then they amy just fling it back together having isolated *a* problem and not have really got to the bottom of it. all I was suggesting is care and caution, I wasn't suggesting the original diagnosis was wrong!!!! Pete

OK, lets start this again. Hopefully I won't get side-tracked by my two sons trying to kill each other Alternatively spun bearings can be caused by the oil pressure being too high due to a faulty relief valve or insufficient contact between the back of the shell and the rod itself. Firstly lets consider why the bearings are a separate part from the rod at all. Well the real reason is simply that they are sacrificial. There is absolutely no reason why you couldn't just machine the steel of the rod to an exact fit with the pin and run it. The problem is that any contamination of the oil, particulate matter etc. would damage the pin and rod surface and once damaged you'd have to throw both away. By using a softish bearing material any particulate matter simply embeds itself into the bearing and the bearing will continue to function without damaging the journal it runs on. When it gets damaged beyond serviceable limits you can simply take it out and replace it with a new one rather than having to buy a new rod and crank, (In this case it's a rod and crank but any plain bearing is the same.) OK, so what prevents the bearings simply spinning in the big end eye? I'll betcha that most people think it's the little tabs on the ends of the shells, right? Wrong! The little tabs are there basically to make sure that the bearing is centralised laterally in the eye of the rod. Yes, they will help a bit to prevent the bearing from spinning but what really keeps 'em still is friction between the *back* of the shell and the surface it sits on in the rod. this is the 'back clearance' and depending on how well the rod is machined and the bearing is manufactured it governs the ability of the bearing to resist spinning. If you remove a rod from a motor and remove the shells you can see by looking at the back of the shell and the inside of the rod where it sits witness marks, (the metal will be a different colour.) which show how tightly the bearing has been pressing on the rod or cap and where oil has been able to seep in between the two. Obviously, since the idea is to prevent the bearing from spinning you DON'T want oil in there so the greater the area beneath the bearing that is a lighter, shiny colour, the better. Guzzi rods are usually pretty good in terms of the rod machining and back clearance.So how does one check this to ensure that the clearance is right before installation? Well, quite simply you can't! What you can do is ensure that the big end is perfectly round, (Or as close to it as possible.) and that the bore of the rod is not tapered or damaged. Then you have to make sure that when the bolts are tightened up there will be adequate pressure exerted on the bearing halves to ensure that they are pressed tightly against this round and un-tapered surface in the bore. So how do you check that? As mentioned before the actual clearance of the bearing is a result of it's manufacture and the size of the journal it runs on. The thing is that the shells are made fractionally larger than the ID of the rod eye. As the bolts are tightened the bearings won't deform enough to change the clearance betwixt bearing and journal but they DO compress against each other forcing the back of the shell into tight contact with the bore of the eye. This force will also try to push the cap away from the rod and it is this that allows you to find out whether there is going to be sufficient back clearance. Take the rod and cap. Clean the surfaces of both where the bearing sits VERY, VERY carefully. I usually give 'em a spray with carby cleaner then wipe them obsessively with a soft, lint free, cloth. Repeat with the back of the shells and then install the shells into the rod and cap. It is VERY important that the face between the rod and cap and the shells be clinically clean as any foreign bodies left in there will deform the bearing, bugger-up the clearance and the ability of the oil film to wedge and shorten the life of the bearing. Once the shells are installed the cap should be placed on the rod, (The right way round!) and the bolts and/or nuts installed with their threads lubricated well with moly paste or some other anti-sieze product. The rod can now be placed in soft jaws in a vice with the jaws clamping the rod part of the big end eye from the side and the two bolts/nuts torqued down to their specified working torque. Once THAT is done you release just ONE of them. When you do this the cap will be forced away from the rod on that side by the pressure the shells are exerting between the two and a feeler guage can be used to measure the gap between rod and cap. This is called 'Measuring the nip' although some joyless bastard with no sense of history has over the last few decades started talking about 'Measuring the *Crush*'! He probably thought 'Nip' was to frivolous and tried to make it more serious. I hate these pompous arseholes!!!!!! I can't offhand remember what the exact spec is but I'd say that for our size journals and bearings you'd be looking at 8 to 10 thou nip. Too much nip and it indicates the bearings are too big for the bore, (Or the bore is too small for the bearings!) and then the shells WILL deform and go out of round as the rods are installed on the crank. Too little nip and there will be insufficient pressure on the shells to ensure they won't spin in the bore in service. Reasons for this can be that the bore is too big or the bearings too small, ovality of the bore or damaged shells, any which way it won't work boy-o!!!!! Once the rods are assembled on the crankpin, (With heaps of moly paste, I use Penrite camshaft and bearing assembley compound, lovely stuff and you can stick it in your bevelbox!) you can check if the clearance is correct pretty easily by simply pulling the rod up to the top of the crankcase mouth and letting it go. It should slowly drop to the bottom of the mouth, (speed will depend on ambient temperature and it's effect on the viscosity of the moly compound.) but it should be smooth and *slow*. If it just drops with a clank the clearance is too big for some reason, if it just sits there like a sodding great errection and you have to poke it to move it then either there is some contamination in the bearing or it's simply too tight for some reason! Yes, you can plastiguage it if you want but if you've measured the pin accurately, the bore of the beaings accurately and know the nip is right then that simple 'Look and Feel' test should be good enough. Works for our racer that last weekend was circulating at Oran park at the same speed and with identical lap times as a 2004 FZR 600 You want more precise? Go and buy a plant in Hamatsu!!!!! Hope that helps. If the bearing had been hammered out of shape in this case the rods, if re-used should be resized and I'd get 'em crack tested too. I'd also double check the piston to head clearance known as the *squish*, (Another lovely old-fashioned term that probably the same joyless bastard has tried to get us to call the 'Quench"!) as insufficient squish clearance is in my experience the commonest cause of hammered out big ends, (Piston hits head at top of stroke, quite often this doesn't do it hard enough to make much noise but the big end shells disintegrate. Double check that the top ring isn't tight in it's groove too, that's a good give-away!) Best of luck with it anyway. I hope that's satisfactory Carl? If anyone has any questions I'll do my best to answer them. Pete

Gladly mate, as long as people remember I'm just a spud-thick mechanic. My forte is explaining things in easily understood terms, I don't claim to be able to give chapter and verse engineering descriptions but I do hope that I can convey not only what is important but WHY. It's the WHY that is so often missing and causes most of the problems! Incidentally, how many of your stable are up and running right now? Is the Sport going yet? I seem to remember that it was giving you a *shirtload* of grief a while back???? Pete

OK, but it's very difficult to tell if the problem is with an out of round or mis-sized rod after the damage has occured. Unless the shell and rod are still sufficiently undamaged to leave a decent witness mark on either you won't be able to tell if it was poor sizing, ovality or a bearing problem. The point I was going to try and make is that it is imperative that if the rods are going to be re-used, with or without the caps aligned correctly, it is essential that they be re-sized and the nip should be ascertained with new shells and roundness of both installed bearings and the journal checked and double checked. If a new crank and rods are being installed then I would STILL, as a matter of course check the nip, (Belive me people this IS the correct technical term!) and, if a decent internal and external micrometer wasn't available, plastiguage the bearings two or three times on the bench in different positions. I would suggest that in this case failure is far more likely to have been due to a discrepancy in rod to bearing sizing rather than bearing to journal. If the same rods are re-used without the sizing being corrected then the same failure will occur again. I may well be preaching to the choir here but I've seen so many *rebuilds* done by people who seem not to remember the basics from their apprenticeships or conversely, because modern motors so rarely go tits-up they've never had to learn them, that I think it's worth making sure the job is done right. If people need an explanation of the whys and hows of back clearance and the checking of nip I'll happily oblige but I don't want to shit people off by telling 'em stuff they already know. Pete

Interesting. I would suggest that the problem may not be down to the cap being on back to front alone, (Although this may of been a contributing factor.). The clearance between a split plain bearing like a big end and the journal it rotates on is essentially a manufacturing thing. The bearing clearance will either be too big or too small or within tollerance. What causes a bearing to spin is too high oil pressure meaning that the internal friction between oil and bearing overcomes the friction betwixt the back of the bearing and the rod or the rod eye being too large for the bearings so that when they are tightened down there is insufficient friction betwixt shel and rod for the bearing to stay in place. (Sorry, gotta go and sort out a little family tiff, I'll continue this a bit later!).....

What's the required ID???? I'll see if i can knock you ups something next week if you like? Pete

Sorry if I gave offence? There was no intention to 'Work anyone over' Pete

Unsprung weight????? Mate you've got a sodding great GEARBOX on the rear wheel spindle, do you really think the few grams difference in weight between aluminium and steel in the spacer is going to make the teeniest bit of differenece????? Really, there is no need to be getting the distance between the bearing registers measured to microns! All you need to do is ensure that when the spacer is installed it is ever so slightly LONGER than that distance so that when the bearings are installed they, or at least one of them, will be slightly off the register. When you tighten up the axle nut what you are doing is effectively compressing a whole series of spacers. (I'm doing this from memory so there may be something I miss, if so I apologise.) There is a shoulder on the spindle that goes through the brake caliper carrier, this presses against the LH wheel bearing inner race, that presses against the spacer inside the wheel, then that presses against the inner race of the RH wheel bearing which in turn presses against that stupid, useless, and to my mind completely un-necessary washer in the interior of the bevelbox. That presses against the spacer in the B-Box housing which, (I think.) then presses against the outer race of the crappy needle roller and finally there is a washer and then the nut. as you tighten it it's just like tightening a nut on a bolt wth a stack of washers on it. They all get clamped up together. Now the bearings themselves are only a push fit into the wheel. A fairly tight push fit but as you know it doesn't take much to remove them. They don't have to be tight in there because their position in relation to the centreline of the bike is kept correct by the lengths of the shoulder on the spindle and the various other spacers being clamped together. The wheel itself can't "Fall off" the bearings because if it tries to move left on the bearings the register of the left hand bearing will prevent it. Likewise if it tries to move right the register of the right hand bearing will prevent it The loadings caused in this situation are pretty low. Ball races like the wheel bearings CAN take a small amount of side loading and they are more than up to taking these sorts of pressures, remember that most of the loads on the balls will be in line with the bearing due to the weight of the machine and the working of the suspension. Side loadings in service are very low and are mainly down to overcoming the gyroscopic forces of the wheel and tyre as you counter-steer like buggery to go round that bend . What will kill them really quickly as I said is if the spacer is too short. If it is then when the bearings are installed they will BOTH settle on their registers in the wheel but because the spacer is too short when the nut is tightened the inner races will be pulled in towards the centre of the wheel until large side loadings are imposed on them, deforming the balls, preventing them from rolling and denying them lubrication as they skid around the races. Result? Very rapid failure!! We had this problem with the front wheel of the race bike early on due to it's odd front hub! "Ah" I can hear you thinking, "But if the wheel bearings are free to *move* in the wheel without being clamped in the registers then surely the wheel won't remain on the centreline of the bike!?" Well, yes, if you had say 2mm of extra length in the spacer that might well be the case. The wheel would have a tendency to *walk* about on the bearings and in all probability it would very soon wear the wheel out around the outer races, not to mention the fact that centreline of the tyre would be moving around the centreline of the machine misalighning the wheels, (Although to be honest I don't think it would be very noticeable, I've seen machines with lots more off-centre than that come out of crates from the factory!). Because though, if the spacer is correctly made so there is only a fraction of a mm clearance once the bearings have settled, the bearing clearance, the friction of the outer races in the wheel and the very minor loadings will mean that the whole sorry box and dice won't move once it has settled and self centred. or if it does the movement will be so small and so infrequent as to mean that no damage will occure within the predicted lifespan of the wheel. When I suggested 2.5mm thickness this was for the wall of the spacer, obviously it's ID needs to be ever so slightly bigger than the wheel spindle but not so large that it can be misaligned on the bearing inner races. I suggest a wall thickness of 2,5mm simply because I reckon that that would be more than adequate to take the compressive forces imposed by the nut when done up by an over-enthusiastic tyre-changing pimply a your average Wottalottacrap-Discount-Tyre-and-Pornography emporium in downtown Turdpoke! Bearings are bearings are bearings! They are all made to ISO standards and as long as the bits they are fitted to/in/with are properly made you'll find that this is such a low speed/low stress situation that even the cheapest and nastiest of them should last pretty much forever! Like all bearings I tend to buy ones from reputable manufactures, SKF, Timken, NSK, NTN etc. and try to avoid ones made by some unknown firm based in Boongo-Boongo land, common sense really. I have to say that I can't remember the last time I saw a wheel bearing fail? About five years ago on a twenty five year old T3 I think . Measuring the distance doesn't need an expensive micrometer, just use a vernier caliper, then measure the spacer you have and see if it's too short. Any wombat with a crappy old Myford can turn up a wheel spacer in a three jaw chuck in about five minutes, all it takes is a bit of pipe with the right ID. As I said the length doesn't even have to be *exact* as long as its a smidge over the length of the distance between the registers so the inner races aren't clamped. Now stop worrying and working yourself into a lather and go and do a couple of simple measurements, go to the local metal-mart and have a dig through the off-cuts bin until you find a bit of mild steel pipe with the right ID, take it to someone with a lathe, get the OD turned down to the correct size and then part it off the right length. Dress with a file to get the burrs off, drop by the bearing shop on the way home, biff it all back together, go for a test ride, come home, drink beer!!! Pete

Oh... Christ on a bloody crutch!!!!!! C'mon guys, they are bloody wheel bearings! They turn over at glacial speeds in terms of roller bearings and will NEVER overheat unless something is wrong!!!!! The C1/2/3 designation is irelevant in this application APART from the extra few microns of side clearance being usefull for accounting for manufacturing tollerances in the wheel/spacer etc. What will, and does, kill sealed roller bearings stone dead is too much side thrust. What will cause this in this application? The spacer being too short and/or being compressed by over-torquing the spindle. The wheel bearings aren't actually *retained* in the wheel in any way, the outer races are just a press fit, (From memory?) in the wheel itself. Therefore the outer race can, and will, settle and find its own *correct* spot within a few minutes of operation. If they needed to be retained they'd have a sodding great circlip holding them in BUT retaining them that way requires all the relevant parts, wheel, spacer, bearings etc. have to be machined very much more precisely than your average mass production line will do. What is a problem, at least on 1100 Sports it is so I'd guess it's likely that the V11 is the same, is that the bearing spacer that goes between the bearings, rather than being made of a decent bit of steel pipe, is made of thin tube with a couple of crappy pressed tin *flanges* on it to help prevent it dropping into the wheel when the spindle is removed. Not only is this bit of shit so flimsy as to be almost impossible to machine accurately, (If it is?) it is so weak that even torquing up the spindle a bit vigorously would be more than sufficient to cause it to deform, it's easy to put hundreds of pounds of pressure on such a thing with a good heave on the spindle nut!!!! If the tube, which may or may not have been long enough in the first place, deforms and the outer races of the bearings seat fully home on their registers in the wheel itself as the nut is tightened the inner races will be pulled inwards and the bearings will be asked to take a side loading they were never intended too. Result? Lots of friction, lots of heat and rapid bearing failure. So why does this aflict 1100 Sports and V11's more tha any other machine? The simple answer is that they are made cheaply and poorly, sad but true. Once again this is an example of crappy execution of a very simple piece of engineering, it's a bloody wheel for fucks sakes, not the space shuttle!!!!! If you want a cure, once and for all, measure ACCURATELY the distance between the two bearing registers in the wheel and have a proper spacer machined from 2.5mm wall tube to that EXACT dimension +0.25mm. Get a pair of poxy 2RS/C3 bearings of the correct type, stick 'em in and forget about it for 100,000Km!!!! As for the crappy little needle roller in the bevelbox? What a prick of an idea!!! It even has a little hole in the race to encorage the ingress of water! WTF is all that about!!!!!!! Pete

The simple answer is that no, it can't be done. Yes youcould probably butcher and hack and eventually get it into the old Tonti frame but so much would have to be changed that you'd essentially be building a completely new motorbike . There is, or at least was, a six speed gear-set produced by someone, (Dutch????) that fitted into the five speed casing at one time. To me it's about as neccessary as a parachute in a submarine, good lord, a lot of Ambo owners reckon that the five speed was an un-neccessary complication , lets face it, one of the Guzzi motor's great strength is it's wide spread of useable power and torque. who needs more gears? There is also the matter of different splineforms on the various shafts and things, it would be a nightmare. Just rebuild the old five speeder, shim it up properly and fit a light flywheel. That will improve a standard early LeMans out of sight with no serious farting about!!!! Pete

Hmmmm, All my Guzzis have always been models of reliability. You want hassle try riding a highly tuned Triumph T500. I eventually went to Guzzi when I got sick of replacing the crappy main bearing bush on the timing side every 8,000 miles. Ride to Paris, come back, split the cases. Ride to Copenhagen, come back, split the cases, Ride to Naples, come back, split the cases, B-o-r-i-n-g!!!!!!! My Guzzis have never failed to get me home, ever! It's been a close run thing on occasion but I've always got home. My now retired Hot-Rod has close to 300,000 miles on it now so I don't think that's too shabby. As for the age thing? All road type Guzzis, even those that have been warmed over a lot, the fatigue life of all the major commonents is damn near infinite. They are made of metal, they have no idea how old they are! If the crankcases were made out of something silly like magnesium, yes, then there would be an issue but generally? Nah. Solid as a rock. Pete

If you think you might of over-revved it and bent a valve a simple compression test will soon say yay or nay but usually if you've bingled a valve it won't idle and if you're lucky in a couple of weeks your sump will fill up with bits of big-end shell. Pete

Nah, I don't reckon it's cavitation, I reckon it's exposure of the pick up due to oil surge rearwards. Cavitation is something else all together. While I'm more than happy to be guided by Mr.Wittner I can't see how changing the way the engine inhales and exhales can have such a drastic effect. I mean more *oomph* should eaquate to better ring sealing, not worse????? I'm certainly not looking for an argument, that was, I'm sure you realize, a joke. I'm just interested in seeing if there is a solution. It's interesting to note that on the late model Calis, (Dunno about the V11's?) the frankcase breather has been moved to the timing chest. The only reason I can really see for this, (apart from making leaky gaskets easier to fis, maybe?) is that there will be less oil being held in suspension in the timing chest rather than the crankcase. Who knows? Not me for one, but I do know my old pusbags are remarkably oil tight. the only drips I get are from the 'Outsider' sump extensions that have sacrificed a bolt. I'm afraid i;'m still 'Old School' enough to refuse to use a gasket sealant on it Pete

Greg, I don't actually think that with this problem the switch is responsible. Usually the poxy things either fail open or fail shut. With the V11 problem it's that the oil pressure appears to drop catastrophically and the light comes on only under hard accelleration. At all other times the wretched switch seems to be operating quite normally. Yup, sticking a guage on it would probably tell the story a bit better but since the problem is only momentary unless you were using some sort of guage with a very quick reaction time, (digital maybe???? I dunno, there has to be something!!!!) it might be hard to spot. With the oil loss? I still reckon that it's probably due to the through-flow of gas through the case and breather system pushing the oil vapor through the frame too quickly for it to condense out. I'm not sure a leak down test would prove all that much, (unless of course there was a serious problem.) I was thinking that with Nicasil you should be looking at about 2% leakage as a ballpark figure. Say the motor is turning 6,000 RPM then you'd be getting 20cc of gas passing the rings every cycle of the motor. 3,000 x 20cc. That would mean a throughput of 60 litres a minute though which can't be right can it?????? Perhaps it can????? I assume that in service the ring seal is a lot better so it must be reduced appreciably, (I hadn't ever actually thought about this before ) but certainly earlier models tend to breathe out oil fairly quickly if the PCV valve is missing or stuck open. Guzzi is also alone to the best of my knowledge in puting the PCV valve BEFORE the oil separator rather than after it. If the V11's don't have a PCV valve fitted as standard then this might well be a contributory factor and fitting one in the breather to the airbox might help oil loss, it would almost certainly help in the prevention of the mayonaising problem. Hey, when I'm in Seattle in a couple of weeks time we can have a long, acrimonious, drunken argument about it That'll be fun . Have you worked out wether your Eldo or Enzo's sofa is faster yet Pete

When I was living in Wolverhampton back in the '80's I too had that problem when I was using my SP for short journeys, it was particularly horrid in the rocker covers! Not as bad as yours looks though, bleargh, that is *really* horrid . My *solution* was to buy a thirty quid Honda C50 to commute on, not only did this save wear and tear on the Guzz but the wreckers are full of low mileage ones that have been embedded in the side of Austin Maxi's so I never did *any* maintenance, when the donks went *pop* I just went to the wrecker and bought another one for 15 quid and bolted it in, (Three bolts! ) it was cheaper than bus fares!!!!!!! It was also a hoot to ride, the tyres were made of bakelite and I could two wheel drift it round roundabouts holding it up with the horrid plastic leg shields like Vallentino does with his GP bike . Nowadays I'm sure you could get a 'Twist and go' scooter that would be even better for much the same money, then you could save the Guzz for solid thrashing which would probably help. Another thing you could try is what people do with Tall Head Tontis that use the frame as the condensor and put a small car type PCV valve in the breather to the airbox, (Shouldn't cost more than a couple of quid from Halfords.) The water, or most of it, gets in from *outside* as the motor cools down and *pants* at low RPM and then condenses inside the frame and cases. fitting a PCV valve helps stop it. Chris Rampen in Canada cured the emulsion problems on his Mk V this way. I haven't actually tried it myself but that's because I live in one of the driest areas of the driest inhabited continent on earth!!!!! I simply don't have condensation/emulsion problems so I don't need to do it and can't comment on it's efficacy or veracity, sorry. I trust Chris though, he's a clever bugger. Pete

Jeff and the boys at Detroit Eurocycle are top folks! Say hi to them from me. I bought my Convert from Jeff, they know and actually LIKE Guzzis and that is half the battle with owning one if you aren't mechanically minded yourself. Dunno about V 11's but when I toured the US on my 'Vert I took loads of tools and didn't need any of 'em. the only thing that went wrong in 7,000 miles of hearty thrashing was that a breather hose fell off, (big deal, I put it back on.) and I fell off, twice, because I'm an idiot I do always carry a rubber chicken though, IMHO an essential aid for any Guzzi traveller. Pete

OK, (Sigh!) Nearly there. The breather system. We've established that the larger the displacement of the motor the greater the pumping action as the pistons rise and fall so the greater the pressure differential between the case *maximum* volume and it's *minimum*. Now lets look at the effect this may have and how the factory has tried to cope with greater or lesser success over the years. The crank whizzing round in close proximity to the oil in the sump will have a tendency to pick up oil particles and droplets from the sump and drag them around in the low pressure vorticees behind the crank webs. oil flung off the crankpin through the spray jets fitted to some connecting rods and the side clearance of the rods will also tend to remain suspended in the air within the case until it hits the walls of the case and runs down returning to the sump. this means that there is always a mist of oil floating around in the air inside the case and this will be pumped out of the breather along with the excess gas towards the low pressure area outside, (The atmosphere.). Initially Guzzi used a collecor/condensor box that was not really much more than a small box stuffed with wire wool. The expelled gas/oil mix went into this via a one way flapper valve in the inlet and the oil particles condensed or were deposited on the wool and then drained back in liquid form to the sump via a return pipe. this at least was the theory. In practice, especially with the larger displacement motors with cast iron bores, the fact that the return pipe returned the oil to BELOW the level it was supposed to be in the sump it was possible under hard running for the crankcase pressure to actually push the oil from the sump back UP the return pipe, flooding the condensor and then puking it out of the breather to atmosphere or in the case of bikes with a rebreather system filling the airbox until suddenly oil flooded down the inlet trumpets, through the carbs and flooding the motor, (Guess how I know this?). To combat this problem Guzzi started fitting a sump extension, basically a one inch spacer, between the block and the sump itself. This had the dual benefits of not only moving the oil away from the spinning crank but also increasing the volume of the case so the pressure varaition was reduced during the cycle aiding the dimunition of the pumping action of the cylinders. On later 1100 Cali models the sump extension has been replaced with a much deeper sump but the overall outcome is the same. They have also over the years replaced the original, and horrid, flapper valve in the breather box with a ball valve and routed the oil returns in various different ways to avoid the pumping back into the condensor problem. With the advent of the spineframes the condensor has become the spine itself. the big box-section of the frame has the crankcase breather run into it, (without any sort of ball valve, (Commonly known as a PCV, Positive Crankcase Ventilation, valve.) in the system to the best of my knowledge. The greater volume of the spine allows for a greater area for the oil vapor to condense and it then runs back down the spine and is returned to the engine via a pipe or pipes to the sump or drain plug for same. The excess *gas* is vented intio the airbox for re-breathing through the motor. To the best of my knowledge the V11's don't suffer from the problem of crankcase pressure pushing oil up the returns into the airbox but the fact that a lot of people suffer oil loss with no visible sign of leaks would seem to indicate that the oil is going *somewhere*. Where I don't know for sure but I'd think that the absence of a PCV valve between the case and condensor may well mean that a lot more oil is expelled into the frame than was expelled into the condensor boxes of earlier bikes. It may well be that given the throughput of gas through the breather system the oil simply doesn't have a chance to condense out as it should and conseuently more of it passes through the re-breather system and is simply burnt by the engine. While this is not enough to cause any obvious indications like crusty plugs it *may* well contribute to detonation as a clean charge is much less likely to detonate than an oil contaminated one. So as to oil *loss* I don't see this as a problem per-se. It's just a consequence, and a fairly minor one, of grossly over-stretching the original design parameters of the engine. What IS a concern is that as a result of this loss the level can easily drop to a point where, under certain circumstances, the pick-up can be exposed and this, as discussed, is BAD NEWS!!!!! So, finally, what can be done about it? IMHO the first step, which is unfortunately the most expensive, is to ditch the broad sump and it's spacer and pick-up and fit one of those German V sumps. Not only will this move the oil further from the crank but it re-locates the pick-up to the very BOTTOM of the sump where it is less likely to be exposed. Yes you loose the provision for the oil cooler but as I said on a pushrod motor terms like 'Tits on a Bull' and 'Ejector Seat in a Helicopter' come to mind, especially on a road bike. Secondly I'd fit some sort of windage tray/baffle plate to separate the oil in the sump from the spinning crank, in effect 'Dry Sumping' the engine. While Enzo has addapted one of my plates for this purpose and still uses his 'Broad Sump' the nice thing about using the V sump is that the windage tray would be child's play to manufacture as the only holes needed in it would be those for the bolts to hold it on and slots in it for oil feed, pick-up and return, the filter is of course out the front and I don't Think the pressure relief valve would poke up high enough to foul he plate. For those wishing to minimise loss of oil, (and therefore refilling.) fitting some sort of windage/baffle plate would certainly help prevent the rearward surge of oil under hard accelleration and the consequent risk of pick-up exposure as well as reducing the tendency of the crank to draw oil from the sump whilst spinning therefore giving the the entire breather system an easier time and hopefully preventing quite so much oil being breathed through the motor. For those unwilling to take the step to the V sump Enzo can probably supply the patern of the plate he's using in his bike. The other alternative is, I suppose, to ride your V11 like an Ambo but i can't see too many owners coming at that!!! As I stated in the first place this is all my own personal theories, they may be quite wrong! Having said that while my experience with V11's is minimal I've found that similar issues with earlier bikes could be addressed in the above mentioned ways with considerable success. If you follow my train of thought and understand how the various bits work and what they need to work properly you'll find it all make a bizzare sort of sense. Having said that I'm *really* glad all mine are 1980 models Pete

OK, on to the lubrication and breather systems. First and foremost you have to realise that THERE IS NO SUCH THING AS *SUCK*! This should be drummed into every first year apprentice with a rod of iron as so many misconceptions about the way stuff moves relate to things being *sucked*. What any pump, be it the oil pump or the cylinders do is create a low pressure area. The greater pressure from *outside* then pushes whatever is being pumped into the lower pressure area. It doesn't matter if its the gaps between the teeth and body of the oil pump or the cylinder as the piston decends, what is happening is that a low pressure area is being created and *Something* with more pressure pushing it will rush in to occupy the low pressure area. With the twin-gear type oil pump as used in your V11, (Or any previous big Guzzi twin.) what happens is that as the gears un-mesh they create a low pressure area between the teeth. Pressure in the crank case forces oil into the space and it is then carried around the outside of the gear in the gaps between the teeth and the pump housing until it is squeezed out again by the teeth on the delivery side meshing again. This makes the delivery side pressurised so it seeks an escape route which it finds through the galleries to the various bearings and thence to the inside of the crankcase. This obviously takes energy which is provided mechanically by the motor and actually robs the motor of power. So, if you want more power, (For a nannosecond or so!) remove your oil pump! Simple, innit!!!!!! The thing is how does the oil get to the pump? Well, obviously it isn't *sucked*, (I hope you're paying attention up the back!!!!!!) It gets pushed by the pressure inside the crankcase which will be atmospheric, (14PSI/1 Bar.) plus a bit from whatever high pressure gasses are leaking past the rings and exhaust valve guide. Now quite simply that isn't much pressure, at least not in *real* terms. and it's trying to push a fairly viscous liquid through a fairly small hole, yes? This is the main reason its NOT a good idea to thrash your engine from cold. When the oil is cold it's more viscous, (Thicker, yes?) so it's going to be a lot less willing to be pushed through a pick-up or gallery by the weedy 17PSI or so in the case. If the oil is *thick* enough what will happen is that as the oil pump gears spin there simply isn't enough time for the space between the gear teeth to fill up with oil so less is delivered. this is what is known as 'Cavitation' and what happens is the pump is effectively pumping *empty space*. Needless to say this empty space provides bugger all lubrication or cooling so your bearings go tits-up! Make sense?????? This is something that designers will take into consideration with an engine when they first set about drawing it up and while most Guzzis won't have a problem if, like me, you set about building a motor that will rev to 10,000RPM you soon discover the limitations of the standard oil pump. My little hot-rod used to torch it's big ends lavishly and with Gusto when I abused it but, unforunately, it was such FUN to abuse I did it often. It gets old very quickly mind So lets go back to the beginning and the V7 through to the 850 T. These motors didn't have an oil filter. Just a strainer on the pick-up to take out the *lumps*. This was bolted to the back of the front of the crankcase (???) and essentially was a bit of bent pipe that stuck down into the sump below the level of the oil. Now lets face it, and I'm sure that Jason would agree, (he has an Ambo.) Those early models wers scarecely fire-breathing monsters that would accelerate so hard that the oil would be liable to slosh towards the back of the sump under acceleration!!!!!! 'Dignified' is the term usually used to describe the performance of these early models and despite the pick-up being at the front of the sump it was unlikely that it would ever be exposed, even under the most extreme, beetle-browed, nongish shows of enthusiasm by their owners. Remember of course as well it was originally designed for the police and military, principally for escort work which is hardly 'Nose on the Tank' stuff! Presumably once the 850 T came out and performance went up a bit,(oh, and the poxy V7 Sport that everyone raves about!) exposure reared it's ugly head. Oddly enough even the earliest crank cases have the cast in bosses for the later oil galleries that were used from the T3 onwards which allowed the fitting of a different sump with a fairly central, bottom mounted pick-up, (Still covered by the 'Lump Extractor') and a different, slightly higher output, oil pump on the crankcase. Post T3 bikes all had this sump which also allowed, for the first time, provision of a *real* cartrige type oil filter. This was located within the sump and required the removal of the sump to change. Remember that. It's important and you'll be tested on this later! This competely cured the pick-up exposure problem but created another one. Namely that Guzzi owners started pissing and moaning about having to remove the sump for filter changes . An added down side was that it made the path through which the oil had to be pushed more restrictive, but having said that I've never found it a problem apart fro m on race engines and guzzi eventually tackled it by increasing the size of the pick-up gallery from strainer to sump on the 1100 models, (Maybe before, can't remember.). This system worked spendidly for a couple of decades but during that time the whining, carping and general stupidness from owners, (Most particularly the Yanks!) about the removal of the sump to change the filter reached a creshendo and rather than payingb a royalty and addopting the 'Harpers Outsider' solution that had been around for years they chose to design their own solution. This first crawled out from under it's rock with the Daytona RS/Centauro Sport and Sport Corsa models which were the first to have the 'Broad Sump' as fitted to the V11 series machines. At Last! Here was an answer to the whiners prayers!!!! In the bottom of the re-designed sump there is a fucking great plate with a 27mm hex in it. Around then outside it has a flange and O-ring to seal it and then a very, very fine pitch thread that screws the plate into the sump. This piece of incandecent brilliance not only is prone to seizing the threads, (especially in cold climates where they put shit on the roads in winter) and is easy to cross thread, necesitating a new sump and plate, but it requires a 27mm hex tool to remove, (Hands up how many shops, never mind home mechanics have such a silly thing ? I had to get one made!!!!!) and it's crowning glory was that even when you got the bloody plate off you STILL couldn't get to the filter without a special filter wrench and 9-times out of ten IT would slip off the oily filter before it came undone so you have to remove the sump anyway!!!!!! Hoorah!!!!!!! Well done boys and girls! What a waste of money and a complete frontbottom of a job has been made of something that was previously so simple!!!!! 10 out of 10!!!!!! Now, to fit this horrid excrecence to the motor required bolting a nasty bit of plumbing to the inside of the crankcase to hold the filter, and, incidentally, the oil pick-up from the sump. The one other thing it allowed was the fitting of a thermostatic control for an oil cooler which is all well and good but apart from with the Hi-Cams which run a lot hotter it's, IMHO, about as much needed as a saddle on a Unicorn!!!!!! The problem is that the oil pick-up has reverted to being a forward mounted *pipe* that just pokes down through the strainer into the sump so it revives the old problem of exposure during hard accelleration. The problem is that these later models like to go!`An Ambo they aint!!!!! Hence the problem with flickering oil lights!!!!!!!! You may of noticed that i haven't mentioned the sump extension fitted to post '82 models? The reason for this is that it has more to do with the breather system than oil delivery and that guys, is the topic for the next little rant!!!!! Pete

OK, first though a couple of caveats. These observations and suggested cures are based on my 1/4 century of farting about with Guzzi twins. They should NOT be taken as definitive answers but are purely my ideas and suggested ways of fixing what I have percieved as a long time Guzzi failing. To start with in any major way the actual Guzzi block has changed very little in 30 years of production. Essentially it's internal volume has remained the same from the V7 of 1967 right up to the current V11 series. What has changed marked ly is the swept volume of the motor. Up from the original 700cc to 1064cc. that's over a 30% increase. It's important to remember that the swept volume is not only above the pistons it's also below it and while the diference between the crankcase's maximum volume, (When the crankpin is at 12 O'clock.) and it's minimum volume, (When the pin is at 6 O'clock.) is not that full 30+% it is still a healthy increase so the amount of change ot the *air volume* in the case between it's maximum capacity and it's minimum capacity has increased appreciably so every revolution it has to cope with trying to push more out and overcome the tendency to try and pull more back in with a V11 than it did with a V7. The bore size has likewise increased from the original V7's (?) 80mm to the current V11's (?) 92mm This makes the circumfirence of the bore larger, (251mm Vs. 289mm.) which means there is a greater area that the rings have to seal. While with the advent of Nicasil bores this is less of a problem than it could be it's still a big step and it's noticeable that models with cast iron bores are a lot more prone to pressurising their cases later models have only 1 and 1/2 compression rings as opposed to the earlier models 3 and new bikes use semi-slipper pistons with a truncated, and shorter, skirt that are more prone to rocking in the bore hindering ring seal. Another factor may well be the longer stroke of the later models. This places the rods, crankpin and webs closer to the surface of the oil in the sump so the cyclonic forces it creates, (Remember, it's spinning 100 times a second at 6,000rpm!) will have a greater chance of dragging oil out of the sump via windage and keeping it in suspension in the *air* within the case. Lastly it should be remembererd that the V7 as a low compression, slow reving slug. Despite it's shorter stroke it was never really designed to be taken much over 6,500RPM. Yes, you can do it but it will achieve bugger all apart from making it sound like a cement mixer full of bricks! You'll still have to use time-lapse photography to establish whether the horizon is coming towards you . Remember too that there is always going to be *some* leakage of gas past the rings and usually a small amount past the guides so over the 720 degrees of the cycle, especially once the motor is spinning fairly fast and is under heavier load the crankcase is always going to have a degree of positive pressure when compared to atmospheric as *some* leakage into the case will occur on every power stroke. It's gotta go somewhere, hence the breather system with a vent to atmosphere, (Or in the case of later bikes a vent into the airbox to re-breathe the escaping hydrocarbons.). That is basically the reasons that they pressurise the crankcase and consequently try and blurt their oil out. I gotta go off and do some work now, (I do, occasionally do this, I'm not at the wretched 'Pooter 24/7 ) but I'll come back later and discuss the lubrication and breathing systems before making my suggestions as to what can be done to help. Pete

Hmmm, look, the oil pressure warning switch operates at some ridiculously low pressure, like 5 PSI or some such. It's effectively useless if it comes on while you're riding. Why? First lets look at how plain bearings work. The important thing with them is that the two surfaces of the journal and the bearing are not supposed to touch. To prevent this they need a constant supply of oil. thats CONSTANT, not INTERMITANT. Put very simply the shaft has to *float* on a film of oil that separates the two parts. If for any reason the supply is interupted, even briefly, then metal to metal contact will occur, this is known as 'boundary lubrication'. Alas it's not quite that simple. Firstly the delivered oil pressure of approximately 50PSI is nowhere near enough to prevent boundary lubrication on its own. The pressures caused by the force of the expanding gas above the piston would easily overwhelm a paltry 50PSI. As the shaft spins though it creates a rolling pressure wavefront in the oil, conveniently at the point where maximum force is being applied to the bearing. This is known as the 'Hydro-dynamic Wedge' and at this point the actual pressure within the oil is muliplied by (From memory?) roughly a factor of ten! The thing is for a decent wedge to form the clearnce in the bearing has to be very exact. This is the reason why both the journal and the bearing have to be perfectly round. Any ovality will lead to parts of the bearings rotation where the clearance may be too great to allow proper formation of the wedge and boundary lubrication will occur. Given that things are happening in your motor much faster than it's easy to imagine lets do a few simple sums. At 6,000 RPM the main and big end bearings are going around 100 times a second. Your big-end journal is 44mm across so it's circumfirence id 44x Pi, which is 3.142. So the circumfirence is 138.25mm (Close enough.) Multiply that by 100 and you get 13825mm, divide by 1000 and you get 13.825 which is the number of metres per second the bearing is moving relative to the journal per second. 13.825M/Sec! Now imagine being towed behind a car at 13.825 M/Sec with your arse on the tarmac! not a nice thought is it!!!!! You'd want a bit of lubrication, my guess it would be self supplied and probably brown!!!!!!! OK, so we've established that we need oil to keep bearing and journal apart. We've also established that we need a constant supply of oil at pressure to form a decent wedge and we also know that the parts have to have the correct clearance and they're moving bloody quick in relation to each other. The second thing that the oil does is remove heat. The stresses imposed on the oil itself create a lot of internal friction between the oil molecules, you need a constant throughput of oil to take this heat away. Even the briefest of interuptions will cause rapid overheating. The bearings themselves are made out of something with a really quite low melting point, lead-antimony or some such, (There are reasons for this I won't go into here.). It doesn't take any time at all for this to melt when oil flow is interupted and when this happens the bearing will tend to 'pick-up' quite simply it welds itself to the journal and then rips free. Once that has happened you're on a short and slippery slope to bearing failure as the bearing and journal are no longer going to have the correct clearance at that point so a wedge won't be able to form. this imposes greater stresses on the remaining parts of the bearing as well as usually allowing more rapid egress of oil thus reducing the pressure and therefore the strength of the remaining wedge. It's a viscious circle and wen it's all happening at 13.825 metres per second it tends to happen pretty damn quick!!!!!!!! That's when you hear the dreaded 'Dogga-Dogga' noise!!!!!!!!! Being a mechanical, spring loaded, switch the oil pressure warning light, (which we've already established doesn't come on until the pressure is way too low.) takes time to come on. OK, not much time but we've already established that it doesn't take any real time for damage to occur. Add in the fact that it only comes on when the pressure is already so low that the oil can't protect the bearings properly, especially in high speed/high load situations and then add in the fraction of a second that it takes the globe of the light to start to incandese and then add in the further fact that you may not notice it immediately, (Especially if you're accelerating hard enough to expose the pick-up!) and I think it's fairly obvious that noticing a winking oil light is a pretty shitty thing!!!!!!!! Why V11's are particularly prone to this and what I'd suggest are sensible solutions are something I can rabbit on about later but only if anyone is interested Pete

It's always been a classic Guzzi problem. Quite simply there isn't enough volume in the crankcase so that until sufficient oil has been ejected to allow the whole sorry business to stabilize it will continue to loose it. The only issue with V11's is that they are a bit prone to exposing their pick-ups if the level is allowed to fall too far. The only folks I've heard of who chronically have tghis problem though are the real 'Hard Chargers' who wheelie a lot or rev it out constantly in all gears. At the end of the day Guzzis have always 'Found their own level' as far as oil is concerned. All three of mine do it. I stopped worrying about it years ago and just remember where on the stick their *level* is and try not to fill it beyond that. Pete

Bruce, I dunno if your ring gear helped but we WON all four races in our class . The Green Goose was flying, even though the track was as slippery as a politician in full election mode. The bugger is that the bike is now overwhelming the clutch and I'm beginning to think we need a 2.50 rim and a 120 tyre for the back Pete

Uhhh! Bruce. I still have *most* of the original Scura clutch, I can weigh the flywheel on it's own if you like, it certainly doesn't weigh very much!!!! Incidentally, the ring gear from your dead unit came in very handy! I had to turn 1mm out of the middle of it and then it was a direct bolt on for our super-lightweight single plate unit we use in the racebike! Handy as when this was aquired it came without a ring gear and I was trying to fart about using a Convert ring gear but it wasn't going to be easy. So, if you get to one of the meets where we're running, (Oran this weekend if you're in NSW!) you can look at the Green Goose and know that part of your Scurra is helping it wheeze around Pete

Go for your life! Nobody will hate you, (Unless they have really tiny brains!). I personally have ridden lots and lots of motorbikes from the small and cheap to the expensive and exclusive over the last 20 years and I still have to find one from any manufacturer that does what I like about my shitty old Tontis any better, and certainly not $20,000AU better! I also modify everything I own from the moment I purchase it and certainly don't see modifying stuff as 'Torture' simply using my skills as a 'Tool using ape' to make another ape's tool more useful for me. Different strokes for different folks as the saying goes. Have fun with whatever you buy. pete