Hi

my 74' 850MkII runs an RGM belt drive with surflex fibre friction plates and standard steel plates plus an RGM thicker aluminium outer pressure plate.

The clutch operation is nice and light, no slipping or dragging.

The problem I have is that the outer surflex fibre friction plate wears excessively against the thick aluminium outer pressure plate.

Maybe I have something wrong in the assembly? Any suggestions what the problem may be?

Skoti,
Try swopping the plates round to put a steel plate next to the aluminium pressure plate or if there's room add a steel plate.

Cash

Hi Cash,

thanks for the suggestion.

there is no more room to add a further steel plate between the final fibre friction plate and the thick aluminium plate.

The only combination I can think of is to fit two fibre friction plates together and then a steel plate with the aluminium plate on top. But I'm not sure what the result would be.

At the moment the clutch is assembled as per RGM belt drive kit instructions, four fibre plates and three steel plates.
Fibre plate fitted first then a steel plate and finally the thick aluminium plate.

When I examine the fibre friction plates it almost seems as if the engine torque is being transmitted only through the outer fibre friction plate. The other fibre friction plates appear unworn.

Still unsure of how to proceed with this problem

I think putting two friction plates together is not so good .
If the alu pressure plate is too thick ,( and you do want a steel plate ) , why not put it on a lathe and remove a few mm ?
Or use the thin steel pressure plate , plus a steel plate in the bottom of the basket .
IMO , the best friction plates are the old full fibre plates , if you can find them , but they must be kept free of oil , so only with a belt primary .
My experience with surflex plates ( on alu base ) is not very good . Friction material AND theeth wear out very fast .

Hi Ludwig,

thanks for your reply.

I have a spare steel plate and the original steel pressure plate so will fit them and post back the results.

many thanks

Skoti

Fitted an extra steel clutch plate and refitted the original steel pressure plate but stack height a bit low, clutch action heavier and rattle from clutch basket when clutch disengaging.

Stripped again and fitted an original bronze clutch plate along with the extra steel plate and original steel pressure plate, stack height seems ok and clutch action nice and light. No slipping, grabbing or dragging when road tested.

Not sure if the original bronze clutch plate will be ok run dry along side the surflex plates.

Hi,

contacted the supplier regarding the wear on the outer alu pressure plate and surflex friction plate, here is the reply:-

the anodising does seem to wear of and produce a fairly abrasive mix, it looks a mess but does not seem to affect the function for quite a while, I put a little grease on the plate, just a smear, anf hoover out the dust that is created in a dry clutch fairly regularly, although that said if you ignore it it just carries on working but does get rather dusty in there, the clutch being of quite an enclosed design retains everything, oil, dust, heat etc, if you need to run high miles then the steel outer plate works without wear

Hi Skoti
I have the same bike, with the same RGM system.
When he sold me the belt drive and clutch basket with plates, he didn't sell me a pressure plate at all, so the stack height was all wrong!!
I made the decision to buy his steel thick plate, not the aliuminium one, as I figured ali was not a good choice of material here....turns out I may have been right...I would send it him back and buy a steel one, then you can bin the bronze plate...remember, two wrongs don't make a right!!
I have no problems with my setup...in fact it is fantastic, one fingered operation...and no clutch slip or drag at all...neutral always there even at standstill.
Stuart.

I use a thick aluminium pressure plate too, and had the same problem. i machined the back of the pressure plate by the thickness of a plain steel plate and then addeed a steel plate last som that it's next to the ally pressure plate. No more wear and a light clutch! Glad I still race my commando, our tridents have a horrible heavy clutch!!

Hi BigStu,

thanks for your input.
A thicker steel plate seems like the correct solution to the problem, but I don't see this part listed in the RGM online catalogue. Would you have a note of the part number?

Hi Seeley920,

thanks for your suggestion which I'll try if I can't obtain a thicker steel pressure plate, meantime it's running ok so I'm reluctant to start changing stuff around in cause I encounter further problems just before I set of to Dijon for the Coupes Moto Legende.

Hi Skoti
I believe the part you require is 060745.
Are you UK based?
The run to France sounds cool, did they change the venue and date?
I was planning doing the French Triton club rally in Switzerland June 6th ish..Thats a great little doo, but I quite fancy the Moto Legend thing sometime.
Stu.

Hi Bigstu,

thank you for the part number.

I am based in the Czech Republic.

Here is the link to the Coupes Moto Legende, I am entered to take part in the track demonstrations.

http://www.coupes-moto-legende.fr/