c20500 Posted February 23, 2010 Posted February 23, 2010 Howdy folks, I've owned several older Guzzi's including a 86' Lemans and an older V50 but I'm new to V11's Is there supposed to be a dry clutch chatter noise when the clutch is pulled in on the V11's (V11 2004 Sport Naked)? specifically a later 2004 model with the crossover just below the alternator cover.. I know the previous Guzzi's had dry clutches but none made any noise like say a dry clutch Ducati? It's not nearly as loud as a ducati's, I'm just checking with you guys if it's normal for the V11's. The bike I'm looking at has only 5k on it and looks to be a well cared for honest example. Thanks Charles
Guest ratchethack Posted February 23, 2010 Posted February 23, 2010 Welcome to the wonderful auditory extravaganza of V11 Guzzi music, Charles. If it ever stops (none too likely), that'd be the time to start worrying. You've got 2 floating friction disks splined on the gearbox input shaft, and an intermediate plate loosely floating on splines affixed to the flywheel all doin' the cha-cha. This is the percussion section of the orchestra. It's the signature of a single pin crank, 90-degree V-twin motor with a 270-430 degree firing order. Best keep idle RPM up to 1200, which will quiet it down somewhat, should the idle have drifted below this. And ain't it grand?
MickM Posted February 23, 2010 Posted February 23, 2010 Hey Charles, I can well understand your fear, but at least you were only looking. When I bought my 02 V11's were really rare in Australia, so I paid up without even seeing one in the flesh and had to get it shipped 2,000km. It rolled out of the truck, I'm all excited, started it and near had a heart attack ! So I rang the dealer and didn't feel all that much better when he laughed and said they all do that. Then I discovered this forum and learnt about broken shift springs, dodgy earth circuits, iffy relays, how the hell you grease the shaft uni's, fixing cush drives, putting grease where Luigi didn't, quelling the vibration, why $30 per litre gear oil is worth having, breathers that split and dump oil everywhere and another heart attack over the prospect of a spin-on oil filter spinning off for no good reason. I'm sure there's more but that's all I can think of immediately. Point is that after you fix all that you end up with a fabulous bike that, for me anyway, I'll never sell. At 8500km in 8 years I'm never gonna wear it out but every time I get on it, even if it's only a trip to work, it makes me feel good about the world. Go for it, you won't regret it.
docc Posted February 23, 2010 Posted February 23, 2010 Hey Charles, I can well understand your fear, but at least you were only looking. When I bought my 02 V11's were really rare in Australia, so I paid up without even seeing one in the flesh and had to get it shipped 2,000km. It rolled out of the truck, I'm all excited, started it and near had a heart attack ! So I rang the dealer and didn't feel all that much better when he laughed and said they all do that. Then I discovered this forum and learnt about broken shift springs, dodgy earth circuits, iffy relays, how the hell you grease the shaft uni's, fixing cush drives, putting grease where Luigi didn't, quelling the vibration, why $30 per litre gear oil is worth having, breathers that split and dump oil everywhere and another heart attack over the prospect of a spin-on oil filter spinning off for no good reason. I'm sure there's more but that's all I can think of immediately. Point is that after you fix all that you end up with a fabulous bike that, for me anyway, I'll never sell. At 8500km in 8 years I'm never gonna wear it out but every time I get on it, even if it's only a trip to work, it makes me feel good about the world. Go for it, you won't regret it. Mick, That is a fine Compendium of Woes! My son had asked me he should really buy a Mini Cooper since the forums showed so many problems with them. If you judged by the posting, you wouldn't think there was a V11 still running in the whole world. Yet, I agree, these bikes are worth working through the little issues. At 10 years/ 67,000 miles the Sport is happy as could be, reliable, and wondrous to ride! Well, there was that little stator failure last year . . .
gstallons Posted February 23, 2010 Posted February 23, 2010 Ditto to Ratch's post ! You can fix this noise by wearing the best ear plugs and a good full face helmet..
c20500 Posted February 23, 2010 Author Posted February 23, 2010 Thanks, I thought it was normal... but just wanted to make sure. Regards, Charles
gstallons Posted February 23, 2010 Posted February 23, 2010 Normal. That is not quite the word but is one that works. As RH said, when it stops making these rackets you need to worry!
rktman1 Posted February 23, 2010 Posted February 23, 2010 When I sold my 2000 Jackal (with 6500 miles) the buyer wasn't familiar with Guzzis. When I pulled in the clutch it made the usual racket and I told him that was normal for the Guzzi dry clutch. I don't think he believed me so I took him around back to my m/c shed where my 2003 LeMans (with 3500 miles) was parked and started it up. Exact same sound. Then he was convinced. When I pull in the clutch I often get riders of other brands that ask if there is something wrong.
MArkS Posted February 23, 2010 Posted February 23, 2010 Odd that mine quiets when I pull in the clutch. Should I be afraid or VERY afraid ?
Guest ratchethack Posted February 24, 2010 Posted February 24, 2010 Odd that mine quiets when I pull in the clutch. Should I be afraid or VERY afraid ? I heard that the green Tenni dual-platers are similar to all the rest in the V11 percussion section, but that they tend to be a little off-beat. Merely hearsay, y'unnerstan'. . .
Greg Field Posted February 24, 2010 Posted February 24, 2010 I heard that the green Tenni dual-platers are similar to all the rest in the V11 percussion section, but that they tend to be a little off-beat. Merely hearsay, y'unnerstan'. . . Tennis have a single-plate clutch. Opposite noises as a result. Not that it really matters, but the noise has nothing to do with the Guzzi firing order, since the earlier Guzzis with the same firing order and dual-plate clutches do not make these noises. The clutch noise started to be noticeable with the advent of really light flywheels, starting subtley with the Sport 1100 and crescendoing on the V11 Sports and continuing on with the two-plate Breva 1100/1200, Norge, etc.
Guest ratchethack Posted February 24, 2010 Posted February 24, 2010 Not that it really matters, but the noise has nothing to do with the Guzzi firing order, since the earlier Guzzis with the same firing order and dual-plate clutches do not make these noises. The clutch noise started to be noticeable with the advent of really light flywheels, On the contrary, V11 clutch racket has everything to do with the firing order. It's the most basic, primary cause, same as it is with Ducati 90-degree V-twins. In order to understand this, it's necessary to comprehend the simple concepts of momentum and angular velocity, and how changes in angular velocity occur within single crank rotations. Since this has been covered so many times by Pete over the years, I figured it would at least be fairly well understood by some who've been here that long. I think I had the simple principles pretty well down on my first engine rebuild as a 12 year-old, but that's just me. Cylinder layout and firing order of a motor has everything to do with the kind of flywheel it needs -- both to idle reliably, and to get any road vehicle underway from a standing stop wihtout a tendency to snuff itself. With a relatively light flywheel, at low RPMs, any motor tends to speed up considerably during the crank rotation of every power stroke, and slow down considerably during the crank rotation of every intake, compression, and exhaust stroke. The primary purpose of a flywheel is to smooth out these changes in angular velocity of the crank, each of which occur once within every complete cycle (2 rotations) in a 4-stroke. Without adequate flywheel mass to stabilize crank momentum, no internal combustion moto or auto engine will idle. Many race motors, having almost no flywheel, will not idle at all, and will snuff instantly at low RPM, with or without load. The trade-off here on the race motor is nearly instant spin-up and relatively rapid acceleration within the power band at WOT, where race motors are designed to operate nearly exclusively. For the most part, full race motors need just enough flywheel to keep them running off-throttle and allow them to upshift with a little throttle chop, and that's about it. If you allow RPMs to drop too far with the clutch in on many full-race motors, you're all done unless you can get it re-lit. A 4-stroke single needs a massive flywheel relative to its displacement in order to idle and deliver tractable power for normal use, since it has only one power stroke for every 2 crank rotations. Both 4-stroke V-twins and parallel twins also need fairly massive flywheels for the same reason, though slightly less so than singles, since they have 2 power strokes for every 2 crank rev's, so there's greater smoothing and more inherent steady-state momentum with twins, relative to singles. The staggered 270-430 degree firing order of a V-twin such as a V11 substantially compounds the angular velocity variations within each cycle, and therefore calls for more flywheel than a parallel twin of the same displacement, since the V11's staggered and uneven power pulses somewhat resemble those of a single, as opposed to the even 360-360 degree firing order of a parallel twin. At the opposite end of the spectrum on flywheel requirements, a radial, dual-row Pratt & Whitney 18-cylinder airplane motor needs no flywheel at all beyond the mass of the crank and the prop attached to it, since its firing order delivers "naturally" less abrupt, more smoothed power pulses with every crank rotation, with 18 power pulses within every 2 crank rotations, (one every 40 degrees). Pete has described V11 clutch racket as a "thrashing back and forth" of the clutch disk(s) and (with the dual plater) the intermediate plate, all floating on sliding splines. Since V11 riders can so clearly hear this every time they ride, I always thought it was relatively simple, self-explanatory, and obvious that this is due to changes in angular velocity within every crank rev. With a relatively massive flywheel like those found on Guzzi Ambassadors, however, there can be almost no change in angular velocity at idle -- therefore, no clutch racket. Ditto with the slightly less massive flywheels of Eldo's and most older Guzzi's prior to the V11. When it comes to the considerably reduced mass of the relatively lighter, lower-mass flywheel found on my Sport, however, the changes in angular velocity of the crank at idle are far more pronounced than on the Ambo and Eldo, and more than enough to cause the clutch components to rattle at idle. Just how significant this is, is easily demonstrated by raising RPM above idle and listening to the clutch. The "cha-cha" decreases with RPM to a point where it disappears. Depending on the load, (or lack thereof in neutral) The rotating mass of the light flywheel (momentum) is only sufficient at higher RPM than idle to overcome the inherent changes in angular velocity of the crank dictated by the staggered firing order. How'd I do, Pete?
Greg Field Posted February 24, 2010 Posted February 24, 2010 Yes, the difference in sound is due to the difference in mass of the flywhweels. That was my point. Also, the six-speed trans apparently contributes to the noise because the V11 Sport flywheel is functionally identical (both are light, 10-spring, dual-plate clutches) to that of a Centauro, but the Centauro clutch (hooked to a five-speed trans) makes less noise. Of course, having knowledge of one or two examples of one model, you could not know these things and have to try to make points by misinterpreting the writings of others with broad knowledge, such as Pete. Anybody remember the special-edition Japanese 4s (nonwierd firing order) of the 1980s with dry clutches and the rattling they made? Light flywheel + multiplate dry clutch= clutch chatter when the plates are released.
Guest ratchethack Posted February 25, 2010 Posted February 25, 2010 . . .(sigh). . . you . . .have to try to make points by misinterpreting the writings of others with broad knowledge, such as Pete. Please indicate exactly where you believe I've misinterpreted Pete. . . .the [rattling clutch] noise has nothing to do with the Guzzi firing order. . . If you also think I've "misinterpreted" this^ unquestionably false statement, please indicate exactly where (Part II). . . .the six-speed trans apparently contributes to the noise [of the clutch]. . . Please provide your best explanation for this^.
docc Posted February 25, 2010 Posted February 25, 2010 At the risk of inserting vulnerable fleshy parts directly into a cat fight, the early six-speed has a "cush drive" (not the cush drive in the bevel box), that increases drive line lash and certainly lends to the lash that would accentuate the "chatter." Problems with this unit were a component of the early gearbox recall. Mine has been less chatty since the change. I know all parties are fully capable of answering for themselves, but in the spirit of having a "forum" I figure I'd chime in. And, I suppose it's just my multi-cylinder background, but is "firing order" the correct term for the degrees of crank rotation between cylinder ignitions?
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