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Clutch problem? Or not ? 04 Lemans


GreasyDave

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Hello all, I am a new member, and have a question for you...regarding my 04 Lemans. First off, I would like to say this is a great forum, I am so glad to have found it. My LeMans has had about 20 assorted problems so far, and I have found documented cases here of almost every one of them, and often a remedy or easy fix. What a relief!

Ok, heres the deal...... My Lemans shifts, runs, and engages/disengages the clutch smooth as silk..... no problems there.... but litterally, with every pull of the clutch lever (in neutral, idling) the motor tone changes (not rpm). Initial start will be a smooth running motor, (pull lever and release) sounds like excessive rattling of the gearbox, (pull and release lever again) and it sounds like a lower end rod knock...alarmingly loud !! Pull and release lever again, and its a smooth as silk motor again. This has not affected performance in any way, nor does it make funny noises going down the road, but its a new issue that has never happened before. Could it just be clutch splines getting worn? Something worse? Normal? Bike has 18K on it. The other 19 problems have all been sorted so far, many with help from lurking around this forum, thank you! Any advice would be appreciated !

Dave

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Guest ratchethack
Any advice would be appreciated !

Dave

Dave, the Guzzi music you hear in neutral at idle is louder at a low RPM idle. This makes perfect Guzzi sense. According to the Maestro of Bungendore, due to the staggered firing order (270 and 430 degrees) of the 90-degree, single-pin crank layout, at lower RPMs, there are changes in angular velocity at the crank WITHIN every revolution -- power pulses, if you will. These power pulses tend to make the clutch do the "Low RPM Cha-cha". The power pulses smooth out with higher RPMs as the flywheel effect takes over, and the "Cha-cha" goes away. The "Cha-cha" actually wreaks havoc on the clutch hub/gearbox input shaft splines over time, eventually wearing them into a "stepped" (destroyed) configuration, which makes for a very expen$ive tear-down & replace excursion. It's one more reason not to allow idle RPM to go much lower than 1200.

 

Hope this helps. :helmet:

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Guest ratchethack
Any advice would be appreciated !

Dave

Dave, FYI, here's the straight info from the original source (the emphasis is mine).

One place where spline wear does very often occur is withing the clutch/flywheel assembley. With a twin plate unit when you engage the clutch, (Pull in the lever.) it de-compresses the friction and intermediate plates. The friction plates are splined to the input hub of the gearbox, the intermediate plate is splined into the flywheel. As the flywheel accelerates and decellerates between power strokes the plates will thrash bavk and forth on their splines and this will eventually cause *stepping* and wear on the splines leading to poor engagement and disengagement of the clutch and in extreme cases 'Creep' when the clutch is engaged at a standstill.

 

This thrashing is only really a problem at low engine speeds and is due to the 270/430 degree firing order of the V twin motor. For this reason it is unwise to set your idle speed low, (Guzzi recommend 1200RPM for a reason.) and likewise it is not good for the clutch componentry to sit at idle with the clutch pulled in. Another completely unrelated reason to keep the idle speed up is of course that the lower the crank speed the lower the oil pump speed. Set the idle really low and you may, in extreme circumstances, not have an adequate oil supply at idle to prevent boundary lubrication.

 

pete

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Dave, FYI, here's the straight info from the original source (the emphasis is mine).

Cool, Thanks for answering guys, and taking the trouble to look it up as well ! So, I should assume that its getting a bit noisier because there is some wear as the miles build up, but nothing to worry about yet? For what its worth, I live in the city, (LOT'S of traffic lights) and have gotten in the habit of not putting bike in neutral till a car has saftely stopped behind me, because I have been rear ended before, (seen it coming in mirror) , but was unable to get it in gear and get out of the way in time. Probably because I was staring in the mirror in disbelief !!!, but just as much to do with i was on a 46 Knucklehead with a foot clutch and tank shifter.... Anyways, I will perhaps bump up the idle a bit, and start using neutral more often! Thanks again, Dave

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A low idle will not wear out your splines. Violently jacking the throttle on and off, or ignoring your cush drive will. RH is merely parroting something he heard but does not understand. A low idle is more likely to contribute to bearing wear inside the engine, not because there's anything per se wrong with a low idel but because the oil pressure could be too low with the engine hot.

 

After all, the bike is almost never under load when idling. When the clutch is pulled in, the plates are loose and under no load. When the bike is idling with the trans in neutral, the plates are clamped together and under no load. If you drive around for 10,000 miles without throttling up, the difference between an idle of 1000 rpm and 1200 rpm ain't gonna make any difference, and you'll spin a rod bearing before you notch your splines.

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Guest ratchethack

Too many automotive clutches to remember since each of my first 2 cars by age 20, and at least half a dozen moto clutches since then, including both moto's I now own and ride. I replaced the clutch basket on the XT600 a few years back.

 

It only took one disassembly and inspection of my Guzzi clutch (with the exception of dual disks, nearly the same as any standard auto clutch) when I had the gearbox out and did a careful re-lube of the splines, to easily grasp the wisdom of Pete's analysis above. It's a simple thing, not much to it. . .

 

Too bad that even with all your vast experience behind the parts counter that you obviously still don't understand the very significant primary source of damage that a low RPM idle represents to the splines. . . :rolleyes:

 

Pretty simple, really. . . But there you have it. . . :huh2:

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You've now convinced me that you've never opened up a Guzzi dual-plater. If you had, and I doubt it, you didn't gain an understanding of what's going on in there. Here's a test: Which specific spline takes the hit? Feel free to Google this to feign that you have some knowledge. I'm a spline reader. I can tell how a guy rides by looking at his clutch bits. I've been inside hundreds of them. Over the life of a clutch, the idle speed makes no difference to spline wear. You're re-inventing the square wheel on this.

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Ok..well, now I am a bit more confused, ..... but, I still have questions...Because I have never taken apart a MG clutch. HD and Triumph, yes, plenty, but never MG. Greg, you say this is completely normal, nothing to worry about, That would be great!! However, I am concerned as to why the sound is now more pronounced than when new. I do not do any throttle jacking, and most of my downshifting is very smooth and easy. I have riden her a little rougher whon my 5 or so trips across west virginia (RT 250, great road) but generally it has been ridden very gentle. Could you please try to explain to me what is going on thats making the noise, and is it a danger to my motor? I have seen both HD and triumph clutch baskets with the grooves completely hammered, but never have they rattled the gearbox this way. Any suggestions would still be greatly appreciated, thanks!

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If you pull in the clutch on a normally functioning V11, it'll sound a little tingley-rattley. If you release the clutch, it may or now make knocking sounds, depending on the position of gears and dogs. What's hapening in the trnas is just shafts and dogs and gears harmonizing with the engine while not under load. They're just rattling around randomly 'cause most of the shafts are spinning but there is no load. The odd firing order exacerbates this. If it does knock, feather the clutch in or out 3-4 times, and you can usually get the knock to go away. Is this what you're hearings? If so, it's entirely normal.

 

Certainly, there could be something wrong with your clutch, but we typically don't see problems with the two-platers until into the 30,000-40,000-mile range, and many go far longer than that. On very rare occasion, one will break the splined center out of a plate. Very rare occasion. This is actually much more common on the Calis than on the V11 Sports.

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Guest ratchethack
You've now convinced me that you've never opened up a Guzzi dual-plater. If you had, and I doubt it, you didn't gain an understanding of what's going on in there. Here's a test: Which specific spline takes the hit? Feel free to Google this to feign that you have some knowledge. I'm a spline reader. I can tell how a guy rides by looking at his clutch bits. I've been inside hundreds of them. Over the life of a clutch, the idle speed makes no difference to spline wear. You're re-inventing the square wheel on this.

. . .[sigh]. . .

 

It's getting increasingly difficult not to notice lately how easily convinced you are of baseless fallacies of your own fabrication, otherwise known as delusions. . . :rolleyes:

 

There are always some people who can't learn, and then there are always those with personal problems, who simply won't learn. So has it always been, and so will it ever be. But how it's possible to leave this Forum on something like a daily basis for years with exactly the same level of ignorance that you bring every day is beyond me. Square wheels again, indeed.

 

If you have a problem with Pete's post above, I suggest you take it up with Pete. Unlike yourself, he has both a full grasp of how Guzzi's work, and a gift for explaining things. More importantly, unlike yourself (Part II) he has a sincere motivation to actually help people, and he demonstrates personal integrity while doing it. MOST importantly, unlike yourself, (Part III) he doesn't seem to suffer from any blatantly obvious, debilitating ego disorder. <_<

 

I reckon Dave and anyone reading this who may have gained an appreciation for Pete's mastery of such things over the years here (a mastery that has always easily trumped yours on his worst day and your best) and knows when they see someone with a terrific ego problem attempt to cover and protect the maintenance of his own ignorance with some bizarre denial behavior. It's a sad sad thing to see displayed so spectacularly in print, particularly on an increasing basis, as you seem to be doing lately. Why it is that you've felt it necessary to go out of your way to demonstrate so much of this recently is beyond me, but it seems to be some kind of a cry for help. I sincerely hope you seek professional counseling soon.

 

My Guzzi's clutch came apart for full inspection when I had my gearbox off 5 years ago. I have never had a gearbox off of any vehicle without doing a full clutch inspection. It's easy enough to do, and it's just common sense. No, I don't recall all the details, having had so many very similar clutches apart over the years (before and since), but I do recall everything being in good shape, including the end of the actuating pushrod (no mushrooming) the pushrod seal was intact, and that there are two sets of splines -- those on which the intermediate plate rides that spin with the flywheel, and those on the gearbox input shaft, on which the 2 clutch disks ride. IIRC, on the Guzzi, the clutch disks can easily be re-installed backwards, rendering the clutch inoperable, but the proper orientation can be ascertained by careful inspection of the length of the protrusion bosses at the disk centers, which are a few mm different front and rear, but otherwise identical front to back. I seem to recall that there's only one way both disks will go back on with the intermediate plate between them, where there's *just enough* clearance between the disk centers. Having studied the thing carefully to note all points of wear (including both sets of splines), it was clear that getting one or both disks backwards would result in either no clearance or too much clearance between them on the shaft, and an assembly that would bind and potentially cause damage if assembled this way. In any case, I got the stack correctly oriented, re-installed and aligned, pressure plate properly threadlocked and torqued to factory spec, and the gearbox back in without a hitch, splines cleaned and sparingly lubed according to Pete's recommendations, and it's been operating flawlessly for over 20K miles ever since.

 

For anyone such as Pete, myself, and I expect many others here, who have both an understanding of how the clutch works, (evidently excluding yourself), and who also understand how the changes in angular velocity of the crank that take place at low RPM idle with the Guzzi motor, and cause the disks to thrash back and forth (evidently excluding yourself, Part II), it's pretty obvious that the gearbox input shaft splines take a considerable beating at low RPM idle (as I clearly mentioned in post #3), and that for most riders not inclined to abuse their Guzzi, this would be the PRIMARY location of spline wear. Simply paying attention to the noticeable decrease in clutch rattle at higher RPMs is about as conclusive of this as it could possibly be. Unlike the clutch disk splines on the gearbox input shaft, however, the intermediate plate can only freely float on its splines on the flywheel when the clutch is engaged (lever pulled in). At all other times the intermediate plate, being fully clamped up, cannot rattle freely on its splines -- at any RPM -- and its splines would not be expected to wear nearly as quickly, unless the rider has a habit of holding the clutch in (engaged) at idle.

 

Now if that's^ not all perfectly correct from my 5 year old memory of dismantling and inspecting my clutch, I'm sure you'll be running it up some kind of a Fraud Flagpole of your own fabrication and staging some kind of twisted ego celebration here, as if this could by some contorted stretch of your obviously twisted imagination, possibly "prove" something to support your lack of comprehension of Pete's clear explanation above, with which you seem to have your greatest disagreement here -- despite your transparent attempt to make it appear that it's ME who's somehow the odd man out on this. . .. :huh:

 

Of course the accuracy of my recall of the above, AND the number of times I've done it, are both entirely irrelevant to the baseless argument you've attempted to launch here, despite your increasingly familiar obvious attempts to twist, obfuscate and derail arguments and make them into something entirely unrelated when you realize you've dug yourself into a hole you can't get yourself out of. Even in the event that my memory of ALL of my clutch inspection were 100% incorrect, none of your sad, dark personal coping problems that seem to be unfolding here would ever trump Pete's understanding, my understanding, nor anyone else's understanding of how it actually works -- INCLUDING the PRIMARY importance of keeping idle RPMs up to 1200 for the long-term health of the splines, as Pete recommends and describes so well, as quoted above.

 

Hope you're feeling better soon.

 

Until you actually do get better (or should I say unless you get better), it might be a whole lot less misleading and confusing for those with a real need for accurate advice and sincere interest in actually learning things here if you made an extra effort to consider the possibility that there are many here who possess knowledge, ability, and willingness to comprehend truths beyond both your own experience, and beyond the increasingly limited capacity to comprehend simple concepts that you've been broadcasting lately. :whistle:

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Guest ratchethack
. . .I will perhaps bump up the idle a bit, and start using neutral more often!
. . .Any suggestions would still be greatly appreciated, thanks!

Coupla thoughts, Dave.

 

You didn't mention what your idle RPM reads, nor is it possible to know how accurate your tach might be without benchmarking it against a known accurate reference anyway, but both Veglia and ITI tachs have sometimes been known to be considerably off.

 

We've had people reporting idle RPMs down in severe low oil pressure risk territory, as low as 800-900 on the dial (accuracy unknown). :o If you think the true idle RPM could be somewhere down around 1K RPM or lower, it might be helpful to find a place where the acoustics are good (an alley perhaps) and listen to the clutch racket at idle in neutral, both engaged and alternately disengaged, and then raise it up above idle 200 or so RPM, and compare. If you notice its clearly quieter at the higher RPM, chances are you need to bump it up. Wouldn't be a bad idea to have the tach calibrated if it's off -- or at least get a read on how far off it is at idle.

 

FWIW, I have a riding Pal with an '04 LeMans who can make distinct changes in the level of clutch racket in neutral at idle by engaging and disengaging it a few times. Next pull and release, it will change back. Mine's always the same. Just another thought, but seems reasonable to me that with 3 disks rattling about on splines in the stack, all with enough clearance to freely "float" when the clutch is engaged, that with any amount of wear, the clearances naturally open up, and the "music" tends to get louder. How all 3 happen to "line up" when suddenly clamped up together as the clutch is disengaged would tend to determine exactly wot kind of "music" comes out. . . Louder music -- clamped or unclamped, at lower RPMs, as Pete explained above.

 

But then, Guzzi music is always good music. ;)

 

Hope this helps, my friend. :luigi:

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