Clutch plate thickness and intermediate warp

[raz]

Having suspected my clutch for some time, today I whacked the engine out of the frame and disassembled it. Seems to me it's worn out and the intermediate plate is warped. Thought I'd check the details with you lot. Bike has 55,000 kms on it. 10-spring clutch.

• Friction plates are riveted type, rivets seem good but total thickness is about 7.4 mm. The "protrutions" in the friction material is only some 0.3 mm at the worst places.
  
• If I put the intermediate plate on a flat surface, I can fit a 0.3 mm feeler gauge under its' outer area (or inner if I put the other side down)
  
• All splines look and feel like new (made me feel happier)
  

So...

1. The plates are end-of-life, right? I saw somewhere for a V11 they are out if they come anywhere near 7 mm.
   
2. The 0.3 mm "convex", that is the warped intermediate plate you use to talk about, right?
   
3. Did the warped plate cause more wear? I haven't noticed any slip, just a very deep engaging point (almost failed to release completely with lever fully in) that I failed to adjust to the better.
   
4. I'm not interested in lightening the clutch but I certainly would appreciate lighter operation. Would a single plate clutch do me any good?
   
5. As long as I just replace plates and intermediate, are these just the standard "big block since 1989" ones despite I seem to have other part numbers in my parts manual?
   

[raz]

Found most answers myself, when reading the english WHB pdf instead of a crappy paper copy in german. Less than 7.5 mm plates should be replaced. I'm pretty sure the 0.3 mm warp is bad and I'll replace it anyway. Oh, and apparently the same plates can be used from 1989 and up to V11 at least.

[motoguzznix]

Found most answers myself, when reading the english WHB pdf instead of a crappy paper copy in german. Less than 7.5 mm plates should be replaced. I'm pretty sure the 0.3 mm warp is bad and I'll replace it anyway. Oh, and apparently the same plates can be used from 1989 and up to V11 at least.

Raz

 

Guzzi quotes 8 mm thickness for a new plate and 7.5 for a worn one.

But when I measured new plates, the starting figure was mostly at 7.7 to 7.8 mm. And I disassembled perfect working clutches with friction plate thickness near 7mm.

 

There is an opportunity to drill and saw in the new steel plate to prevent the new one from warping. Drill 6 holes of ~3 mm into the steel plate in 60° distance in the middle of the friction area. Saw in the plate from the outside to the first hole , the next from the inside etc. There is a description of this modification somewhere in the net, but I can't remember where.

[raz]

Raz

 

Guzzi quotes 8 mm thickness for a new plate and 7.5 for a worn one.

But when I measured new plates, the starting figure was mostly at 7.7 to 7.8 mm. And I disassembled perfect working clutches with friction plate thickness near 7mm.

 

There is an opportunity to drill and saw in the new steel plate to prevent the new one from warping. Drill 6 holes of ~3 mm into the steel plate in 60° distance in the middle of the friction area. Saw in the plate from the outside to the first hole , the next from the inside etc. There is a description of this modification somewhere in the net, but I can't remember where.

Thanks Ernst. I saw that too though I recall cutting all of them from the inside. Even so, I find that a bit scary. My impression is most people don't have the warping problem so my first shot will be to use it as is. I do have a proper clutch spring preloading tool, so I hope that will do the trick.

[Phil A]

Thanks Ernst. I saw that too though I recall cutting all of them from the inside. Even so, I find that a bit scary. My impression is most people don't have the warping problem so my first shot will be to use it as is. I do have a proper clutch spring preloading tool, so I hope that will do the trick.

The warping may be a sign that things have been warm at some time.

 

I would recommend the mod Ernst has mentioned.

[motoguzznix]

Thanks Ernst. I saw that too though I recall cutting all of them from the inside. Even so, I find that a bit scary. My impression is most people don't have the warping problem so my first shot will be to use it as is. I do have a proper clutch spring preloading tool, so I hope that will do the trick.

Raz

 

I disassebled a lot of guzzi clutches and the intermediate steel plate was warped on almost every clutch. With very low mileage you might have the chance to find an unwarped plate. This makes the clutch engaging point unstable and eventially the clutch fails to disengage.

 

I did this mod on my own V11, but only 7000 km since then. No problems, but this in not really a durability statement.

[raz]

I disassebled a lot of guzzi clutches and the intermediate steel plate was warped on almost every clutch. With very low mileage you might have the chance to find an unwarped plate. This makes the clutch engaging point unstable and eventially the clutch fails to disengage.

 

I did this mod on my own V11, but only 7000 km since then. No problems, but this in not really a durability statement.

OK, thanks. I'll look into it. For future readers interested in this, the english instructions is at guzzitech.dk

[raz]

For the record: when measured more carefully, the intermediate plate was warped 0.7 mm that explains some clonking and shift problems!