mike wilson

Dave has made the point I was going to; that Motoman's examinations are considerably less than his builds, so it's not easy to draw real conclusions. WRT your penultimate paragraph above, I have to disagree. _All_ mechanical things need running in to some extent to get the best life and performance out of them. All we are discussing here is the methodology. One could argue that the high pressure line contact of gear teeth is a good analogue to the ring/bore interface and therefore needs the same treatment. The same for the roller bearings found in gearbox, drive and wheels. I'm not suggesting for a moment that Motoman is doing anything scurrilous. I'm not even stating that he is wrong. I just find some of his statements to be somewhat ambivalent. I would also like to see some hard numbers. For instance, what is the difference in ring seating pressure between an engine at tickover and one at full throttle? Order of magnitude? Or less? Although it seems to make empirical sense that pressures will be much higher, will that increase make a practical difference to the bedding of rings? My contention is that the first minutes of an engine's life is what decides its fate. In that respect, it would make more sense for Motoman (not me.....) to advocate his methodology to be applied from first run. By advocating a preliminary warmup (which is where I think most effect will be) he is reducing, if not negating, the effect of the procedure. One may think that the procedure has worked when, in fact, it was the preliminary run at the factory that bedded the ring in. You were just lucky in your choice of dealer mechanic afterwards. These two sentences: As Pete has mentioned, plain bearing motors, especially today, including the Guzzi, with respect to "the rest of the machine (gearbox, final drive, wheel bearings, all the walloping bits in the cylinder head, etc.)" don't require ANY break-in wotsoever. As has been pointed out many times, the Guzzi has an extended break-in, which would seem to require more careful attention over more miles than other kinds of motors. seem to be rather contradictory.

Very interesting thread so far. Pity I was away over the weekend - there was much to jump in on. So, a few more penn'orth. First of all, a postulation: the wear between a new cylinder and rings follows an inverse logarithmic pattern. That is, the first stroke procudes the most wear. The next stroke quite a bit less. The next stroke a bit less again. And so on, until each stroke produces virtually no wear. Until, at some point in the future, some factor is exceeded that causes wear to accelerate again to the point of needing repair/replacement. A graph of the wear would look like a very open letter "U" with the right hand leg not rising as much as the left. Maybe a back-to-front letter "J" would be a better analogy. Is this generally agreed to be a reasonable picture of what goes on at the bore/ring interface, all conditions being normal? If the above is true, it is the _very_ first strokes that cause most wear by a large margin. This is where I find Motoman's logic to be flawed. By the time you have warmed up your engine (what? 20 minutes to get a decent sized lump up to temperature?) for the first time much, if not most, of the serious wear has already taken place. In a sense, it doesn't really matter what you do. At least, as far as the ring/bore interface is concerned. It's already done what it's going to do. For the rest of the machine, it may well be a different story. Putting aside the "special circumstances" of ring/bore seating, it seems that nobody disputes that the rest of the machine (gearbox, final drive, wheel bearings, all the walloping bits in the cylinder head, etc.) need to be treated gently to produce the best life. Motoman wants you to do exactly the opposite. For his hypothesis to be functionally true, one would need to have a system of externally warming the engine and then apply the procedure from the first cough. Is there an answer? Is there pills! The reason why some machines don't seal well? For me, I would be questioning exactly what happened to them in that first twenty minutes, when they were tested at the factory or run during a PDI. That's where the fate of your machine is decided.

From the page: ========================================== So why do all the owner's manuals say to take it easy for the first thousand miles ??? This is a good question ... Why would Yamaha recommend a break in method which will prevent the rings from sealing as well as possible ?? This is a good question ... Why would Honda recommend a break in method which will prevent the rings from sealing as well as possible ?? This is a good question ... Why do the manufacturers recommend waiting until 600 miles to flush out all the loose metal ??? This is a good question ... =============================================== None of which he answers..... I understand that some of them may be rhetorical but I would really like to see his explanation for the first. I'm also curious as to why he specifies four strokes for this procedure. I assume two strokes are excluded, which I find odd. He may have a point but breakin is, as with most things, a compromise. Gas pressure is what seats rings. Making the pressure higher _may_ help to seat rings slightly better but it seems to me that modern manufacturing and materials are having a bigger say in better sealing than some form of driving methodology. In any case, the methodology is not one easily applicable with some modern machinery. I'm not sure I would be comfortable making full throttle passes in second gear on, say, a brand new FJ1400 on the way home from the dealer. If it is even possible. The time taken (running the engine at outputs it is likely to endure for most of its working life) to get to a suitable place to do it would probably outweigh the theoretical benefit. FWIW, I have always run in engines by treating them carefully - neither slogging or going into the higher reaches of their capabilities and making sure that they are warmed up before using more than modest throttle openings - and have never had any problems either. At least, none that weren't designed in....

Having had the dubious pleasure of removing the left hand cylinder from a BMW (can't remember the model but it was a sidevalve - cast iron, none of this namby-pamby aluminium) by applying it with some effort to a mountainside, I can attest to the extreme force needed to do this sort of thing. I do wonder, however, about the effort needed to displace the cylinder at its joint with the crankcase. It is located by a combination of the hole bored into the case and the head studs. It could be possible to slightly twist the cylinder/head combination about the longitudinal axis. The giveaway would be a leak from the base gasket, I suppose.

Pine Marten, Mustela martes. Generally about 50cm. 100cm would be an Arnie amongst Martens.....

Aren't there anti-chatter/squeal shims/clips for this sort of problem? One man's squeal is another's chatter. 8-) It's just a matter of frequency.

After months of seeing nothing but cruisers, bm's and squids, I saw three Guzzis in one journey yesterday. First looked like an early Spada going in the opposite direction at a rate of knots. Second a V11 of some type (red....) by the side of the road, hopefully not broken but there was too much traffic to stop. Third ditto, doing what the Spada did. All on the A19 in NE England. Lovely day.

I'll go with Greeves too, for now. 197cc and 1971.

You folks are just too, too kind. 8-)

Thank you. It suprised me when I found it, too. Would like to know more but there's little online. I have some (Russian) books on their motorcycles. I think I'll do some scanning over the weekend... On Lou's (produced by Bowie) Transformer album, there's a song called "Satellite of Love"

It's doomed. From the bike description page: "alloy timing gears"

1964 Vostok Grand Prix 350 USSR Apparently an almost identical copy of the MV of the time, four were made. I can't find any record of them ever racing. Vostock was the Soviet capsule that carried Yuri Gagarin into space.

Aren't they all? Ice-nine.

Kurt Vonnegut has shuffled off. http://www.nytimes.com/2007/04/12/books/12...amp;oref=slogin I know some here will be saddened.

Looks like I will be telling you in the morning.

Outfits are like _nothing_ else on the road. You have to learn riding from scratch. Trikes are possibly less stable than an outfit, as the outfit at least has two wheels on one side. Both of them are formatted the wrong way round. Two at the front, one at the back is _much_ more stable.

Names, Nigel, names. Bike setup 101. I've seen some people riding with controls set nearly 90degrees from arm line. I could never get the hang of Lambrettas. Others I have found useful: Footrests under the nose of the seat. Adjust height to taste. Straight line between the centre of the left and right handlebar grips goes over/through the steering head.

http://www.motomeccaspares.com/shop/browse...wse&feed=BS Plenty of caliper o/haul kits listed. I don't know what number to look for.

One last clue. Somebody should get it from this. Not a one-off, although not many (single figures) were made. An almost direct copy of something else.

The big advantage of Herron heads is in the production engineering area. Multicylinder engines' heads need quite complex machining operations on all cylinders. If the machine has one head for all cylinders, it is easy to gang the mills/drills and whatever so that all cylinders are worked on at once. You can then cut all the intake machining at once, reset and cut all the exhaust. If you have one head per cylinder, that is two loads of setting up per cylinder, rather than per machine. If you have the parallel bores of the valves of a Herron head, you can do all the work in one pass. Properly designed, as the Guzzi ones seem to be, the disadvantages of the poor gas flow are reduced.

Very warm indeed. Now be a bit more oblique.

Getting warmer.

You're right Ben. On both counts. Although I find many faired bikes remarkably difficult to differentiate. You're wrong DH. This is more enjoyable than I thought it might be. Another clue. David Bowie and Lou Reed wrote a song about one of these. (Sorry, there's no point in making the clue easier than the picture)

It's a clue. Don't read it literally.

No, no, etc. Stuff your hints. 8-) OK, I relent. Note the engine has a lot of _space_ around it.