raz

I'm just a dilettant amateur so this is merely random input for you: I love my Z6 front and my Z4 rear will be switched to a Z6 next time, that's for sure. Front spacer should sit on rider's left side. Pressure is fine. If you have bent rims you'd notice in the straights too. There are threads here somewhere dealing with swing adjustment so the rear is in line. You might want to check that. You might also want to check steering head bearing, and play. Pretty easy check. Stuff some grease in it when you're at it, it is always needed. My way of checking wheel bearings is take wheel off, put finger in bearing and turn around. Any un-even sensation is bad. Bearings are cheap. I don't know if this method is the Right Thing™ but it works for me so far. Last... if you haven't owned the bike since new, just consider the possibility the frame's been bent. Let's hope you don't even have to go there, but it may be next thing to check. There are ways to determine this, like triangle measuring, or loosening engine mounts and see where the subframe wants to go. There are threads on this too.

It's a Stucchi. It cost me €15 (US$ 20) and that places it way way above everything I ever bought to my bike in terms of bang for the bucks. Where I live it equals the price of half a tank of gas. Clock says 46,700 kms (some 30,000 miles) but I only owned it since 35,000 kms so who knows? Might be 146,700 for what I know. Or some PO might have used olive oil in the engine, or sewers water. I'm starting to trust it now I've been inside everything but the gearbox. I can tell someone has been there though, lots of grey liquid seal all over the covers.

What's with that downpipe, is it rust? That is known to lessen weight

Thanks. Feels great! And for once I over planned it instead of ending up bodging. Yes, I will not urge everybody they should do this mod, but Ratch, you're next, no? A couple of times you have raised the question if the original tensioner can be modified. I guess it can, just change the spring to a harder one, but given the price of the Stucchi I'm not sure it's worth the trouble experimenting. It would be plenty of work between tries. Also, the Stucchi/Valtech is a very proven design, isn't it? I think Pete said he has seen some broken springs, but I don't think a broken spring will do any harm unless it breaks in three parts. And that would be pretty wierd wouldn't it? The design assures good tension even with a broken spring.

I had that sympthom after winter. It felt as "controlled wobble" but it was not a good feeling. Low amplitude, low frequency. At first I suspected the pattern of the new front tyre. During winter I had counted clicks on rebound and compression screws, and then set them to lower damping. Apparently somewhere in the process I counted from the wrong end on one of the screws, from fully in instead of fully out. This apparently produced a very bad setting, with much higher damping in one of the directions. After fixing that it was rocky steady again. I was amazed it made such a big difference.

OK, now made a decent test ride. I can tell you this made a difference to the better. No ringing noise. In fact no noise at all, just the (to me) normal chain sound that I've never heard before on this engine. Idling is rock stable, it's like a Toyota V6 I used to own (I really miss that one). After getting the oil up to some 95°C, I stopped and let it idle for several minutes (until dipstick thermometer passed 100°C). It never missed, never varied at all. If I wanted to I could probably set the idle to 600 rpm but people have told me it's not a good idea. Low yet steady idle is cool though Strobed it too, but there wasn't really much to look at, since it never missed or made any variation in speed.

Tried again today with engine really warmed up and WOT. Left 9,25 (just above 130 psi) Right 10.5 (150 psi) Thats 13,5% or 11.9% depending on which way you calculate it. I'm pretty sure my heads are to blame and not the rings and barrels. Ah well, it will be interesting doing a comparison after the upcoming head overhaul...

This must be the best thread ever

I fail to understand this. Maybe the V11 reaction rod is different from mine. What is the uniball?

As far as I know (I don't have much hard facts on this and I've been wrong before) modern cables does not need lubing, and in fact may suffer from lubing (if you happen to use a lubrication not suitable for whatever long life magic and teflon stuff in there). Ratchethack, on the other hand, will probably tell you lubing is good, and preferably with Redline Shock Proof Heavy (I think he's tempted to drink that stuff). This puts you in a good position: you can chose for yourself Seriously I don't think it is needed but I don't think it will hurt either. Much more important is to avoid any sharp bends in its routing.

What, should I measure exactly 4 comp. strokes? Or at least 4? This is a cheap gauge with rubber cone inlet that I push to the spark plug hole. It remembers the max value so I just ran the starter until the needle didn't move any more, and then some. At least 5-10 compression strokes.

Uh... how do I get the strobe light out of phase? Maybe you mean I myself was 180 degrees out of phase... watching the Valeo starter instead of the flywheel inspection hole Well, that's plausible... but no.

Thank you, throttles were closed (I did figure that one out, but only later) and engine was not quite in temperature. I'll redo the test some day after riding. I'll also test a friends similar engine, a curious comparison. I feel like a kid with a new toy

When I bought my strobe lamp to check scatter, I also got another toy, a compression tester. Now the only problem is I don't know what it should read I guess doing this the right way involves checking/setting valve clearance first, right? Or would a little difference there not do much on the compression readings? Then, what are good readings on a Guzzi 1100 in absolute terms? And what are rules-of-thumb for relative difference? I already knew my heads are due for an overhaul, this is just for fun and curiosity. My current readings (without setting valve clearance first): Left 7 kg/cm² (100 psi) Right 8.3 km/cm² (120 psi) So, doctor, how bad is it?

All done now. I found a new M8x1 nut (they are not common even in Europe) and had to freshen up the shaft threads a little after the abuse. Man, I'm glad I found that time bomb! Unfortunately I can't take it for even a short ride cause I'm alone with kids all evening. But I've done some strobing. Engine was not warmed up as thoroghly as yesterday though, just from idling. Anyway, reading is rock stable. No scatter at all. It's like looking at a whole different type of engine. What is strange though is that yesterday I couldn't see any marks at all on the flywheel. Today I saw a crisp and steady "D" for the right cylinder and "S" for the left one. I really looked for it yesterday but saw nothing. I'm not sure why Idling was very stable too. And no ringing noise. It will be a very very interesting ride tomorrow. Thanks all of you!

Still, the question is, are the scattering due to a far too weak tensioner (and fairly good chain), or just a bad chain? I have nothing to compare to, but actually I think my chain is not in the best condition. All papers I got with the bike (dating a couple of years back) backs up the mileage on the clock, but I still can't be 100% sure it just has 46,000 kms. If it has, the chain should really not be bad. But, again, maybe it's 146,000 kms, or something else. Even so, consensus is that the original tensioner is really weak. It probably won't hurt replacing it, and it's by far the cheapest of the alternatives I had. If it masks the sympthoms of a marginal chain for another 50,000 kms it's worth it. If the ringing noise disappears, I'll be extatic. If it lessens the OEM ECU's problems, that's good too!

Yes, keep in mind my primary goal with this is to see if the horrible noise I've got from the chain will disappear. The idle stumble is no problem when I use the My16M, and little problem when the original ECU is in and everything is tuned perfectly. The noise at idle, however, remains. But one fact I've established today is the chain can not touch the housing regardless of how bad the tensioner is. I wonder if the noise could be a bearing in the oil pump, or something like that. Since noone came up with any ideas when I asked here in the forum, I figured this was a cool and fairly cheap project just to try and narrow it down. OTOH, my timing chest cover is still off. Is there some good way to check pump bearings health?

First pass complete. I have to replace the oil pump sprocket nut. Some idiot PO (or shop) had forced a wrong thread nut on, together with glue(!). I'll have to wait until tomorrow getting one and putting it all together. It's a M8x1, not the regular M8x1.25. Some notes: On the Sporti, loosening the oil cooler mounts and pushing it down is enough. All pipes left intact and oil left in sump. Removed front wheel and fender. Removed fuel tank. And downpipes. Removed rear upper bolts and engine bolts from subframe, Tilted subframe forward with frontmost bolts just loosened a bit. Removed alternator stator and rotor. Unbolted timing chest cover. One gentle blow with a rubber hammer and off it went. Gasket was a metal type (not reusable) so I have a new paper one ready. Removed oil pump sprocket nut (13 mm socket). That was far too easy, because it was just a wrong thread nut glued to the shaft. This alone make the project worth any money and time I put into it... It could have come off anytime, and since the Sporti have its' oil light hidden behind the fairing I wouldn't have noticed until rear wheel locked up. Removed cam sprocket nut, 27 mm socket. It came off pretty easy, with a screwdriver locking the starter gear. A rattle gun can't be used unless you remove the subframe completely. Unless it's a slick one with 90 degree angle maybe. Removed crank sprocket nut with a 32 mm wrench. The shaft sticks out 90 mm so no normal socket will fit. I put the ring wrench on, then a 16mm spacer (a roll of electric tape), then the alternator rotor and its' nut. This way the wrench was locked in place and wouldn't slip. I had a curious neighbour lock the starter gear and the nut came off without blood spill. Wiggled the three sprockets until loose, and removed all three and the chain together. Watch the keys on crank shaft and oil pump shaft! The oil pump one you can remove, it's put back after the sprocket is in. Removed old tensioner. One of its' bolts have no use after removing, and the resulting hole does no harm. The other bolt is one of the front main flange bolts so it has to be put back. But, warning, the old bolt is too long! I did not realise that at first, and what happened was the crank counterweight, or something, knocked into it (on the other side of that barn wall) when I had it all reassembled and rotated the engine with a wrench. I thought it was valves hitting pistons, and it took me a good part of the evening figuring out I had assembled chain and sprockets correctly, and this bolt was the culprit! Replace the M8 x 35 mm with an M8 x 25 mm. This is ordinary hex M8x1.25 and 8.8 grade. Installed new tensioner with two of the other front main bolts. See Pete's PDF, the Valtech tensioner looks the same as the Stucchi. At this point, I had the spring and blade removed from it. Put chain and sprockets back. Watch the marks. Put the oil pump shaft key in (see PDF). Install blade and spring on tensioner. Some people don't use the spring. I did. Nuts back, loctited. The cam one is spec'd to 150 Nm. I couldn't use the torque wrench on the crank nut so I just tightened it up to what felt good. The oil pump nut is just M8 so I'll use a standard value plus VAT, summing up to maybe 40 Nm. But if it feels right, I may stop before it clicks. This tensioner is... no let's put it another way. The original one did not tension the chain. This one does. It's a huge difference. But I'll have to wait until tomorrow to find out if that actually fixes my problems. I noticed I could probably fit a feeler gauge between outer and inner links in the chain, if you get what I mean. Does this fact alone say my chain is due to the floatation test? I'll measure tomorrow anyway. Yeah, the phonic wheel clearance was between 0.6 and 0.7 mm. I won't touch it.

I just remembered I have one more fact to indicate we are on the right track: When using Cliff's My16M, the chain whip is not by far as self-amplifying as with the original ECU. Probably MyECU deals with borderline signals from the pickup much better (I think at some times, like when cranking, it reads the signal into an ADC instead of using the digital signal from discrete circuitry). So the sudden will to change rotation doesn't happen, for instance. I'm currently installing a roperplate. Pure therapy. Weather looks promising so I'll probably have a go at the chain tomorrow. I tried buying a strobe light again today at what I thought was a logical store to buy one. They didn't even know what it was . This makes we want one even more (before they start costing huge money at pro stores) so I will try again tomorrow at a proper car parts store. Hopefully they are open Sundays, I think they are. When I'm done with this I will store the strobe light together with my vinyl record player for use after WW3

I'm desperately trying to convince myself doing a cam chain job in the one-wall carport while it's raining is a Bad Idea™. I have the option to take it inside my living room, where I had it all winter, but GF tend to dislike that. Also, my first try buying a strobe light resulted in zilch. Not many need those nowadays... The timing chest cover can be removed with sump full of oil, right? Oil level should be way below that.

It's checked with cam sprocket removed, with a feeler gauge (it's called that isn't it?). There's probably no need to check it unless rebuilding the engine since it won't change over time, but I suppose it's possible with some imagination, like your examples.

Could a tiny exhaust leak render such sympthoms? Why?

You two really make me laugh at least once a day! I feel for you Ratch. I get so frustrated dealing with computer sales and support, I'd often rather throw away a faulty computer than try to claim any warranty. With a price on my own time, I figure it's even worth the money in the long run. I come to think of the fax machine slaughter ritual in Office Space I'm sorry for the noise, I can't help with the original question

Interestingly enough my WHB (for a Sporti) says 0.6-1.2 mm. I'll set it to your spec's as they are subrange of mine.