850 shim pate for clutch

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jchill

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I am need of a thinner plain plate in my 850 clutch basket
Using Barnett friction and factory plain plates at present

Old Britts did have a .65 plate (factory plate is .80) but no longer will offer this.

Was wondering if anyone still makes anything similar to this
Also if anyone has experience in this would like to know how much difference this could make using a .65 vs .80
I.E. Is one plate all you will need
Thanks all
 
Hey John. WINO Steve here. I don't remember you having clutch issues with your bike. If you do need something special and Barnett or Fred doesn't have what you need give Matt at Colorado Norton Works a call. If he can't hook you up he will know who can.
 
Your clutch stack is too tall for the basket? Wow! I didn't know that could happen! You don't have a spare steel plate laying in the bottom undetected do you?

What thickness is your pressure plate? Maybe a 750 pressure plate in there?
(.225 vs. .102)

It is also possible that the friction plates are .145 thick instead of the intended .120 thick for the five friction plate clutch.

Time to start measuring everything.
 
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I am know it is unusual but in researching it does happen especially on a 850
A friend had same issue on his and diagnosed this as likely cause and fix

The pressure and plain plates are sock size per Old Britts site and was confirmed by measuring before I reinstalled ploates
Have checked and rechecked adjustments so I hope this can prove to be my solution
I
 
It is always a bit of a puzzle. It would be interesting if you are able to measure the distance from your backing plate to the groove for the circlip. You have to wonder if some of them where machined differently. Otherwise it is all about what gets stacked in them. So yes, if your stack is too high, you can search for thinner friction plates, find thinner steel plates or machine some off of your pressure plate.

DBR grinds Commando brake discs, he might be able to do clutch discs. Otherwise a number of nights with a piece of sandpaper on a sheet of glass. Put on old movies and start sanding.

I moved my diaphragm .020 closer to the clutch stack to ease my pull on the clutch cable. It made a noticeable difference. So I assume going .015 the other way would too. What is it that your clutch is doing that you want to change?

Russ
 
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PS - I discovered I had some friction plates that were warped (Barnett style) and I could measure them and they were within spec. I would put the clutch together and the stack measured higher than the sum of individual parts. When the diaphragm put pressure on them they would compress to the correct height for the sum of the parts. I never noticed a problem with these riding but it was a real problem trying to adjust the stack height for my desired diaphragm deflection until I figured this out.

I don't know if this story will help with your problem, or with anybody else here, but it is worth taking a look at. I had previously checked my steel plates by marking on them with a felt tip and then burnishing them on sandpaper on a sheet of glass. The idea being that the felt tip markings would reveal whether they were flat as they were removed. The steel plates where flat. Originally it never occurred to me the friction plates might not lay flat.
 
vrich
I likley need reduced pressure on the spring plate
Old Britts does sell slightly thinner plain plates but I think I would need at least .15 - .25 to make a difference
I wont know till I fit them
After Christmas I will open the case (again) and remeasure thickness
I will be asking around to see there is a shop that can thin out a plate
Happy Holidays to all
 
jchill said:
vrich
I likley need reduced pressure on the spring plate
Old Britts does sell slightly thinner plain plates but I think I would need at least .15 - .25 to make a difference
I wont know till I fit them
After Christmas I will open the case (again) and remeasure thickness
I will be asking around to see there is a shop that can thin out a plate
Happy Holidays to all
Click to expand...

John, Have you given Matt at CNW a call??? Your solution is probably just a phone call away.
 
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I seem to have the same problem. I've had it for years. It's not much of a bother but now that I am homing in on perfection in all other areas, I'm working on a solution. Basically, with the clutch adjusted as per the manual, the clutch drags, I have to adjust the clutch with no play and then give it a few more clicks to engage neutral easily. The clutch has never slipped since I fitted Barnett plates and a new clutch centre over 40,000 miles ago. I have printed out the clutch stack height info, and I'm going to pull the clutch next week and start measuring. The clutch isn't terribly heavy, quite manageable in fact, but I rode my mate's 750 Fastback a while ago and it was so light I thought the cable had snapped ! Time to do something.
 
LAB That was a mistype as I need more clearance from the circlip ring
Thanks for catching it as that would confuse the issuie
 
Fullauto said:
I seem to have the same problem. I've had it for years. It's not much of a bother but now that I am homing in on perfection in all other areas, I'm working on a solution. Basically, with the clutch adjusted as per the manual, the clutch drags, I have to adjust the clutch with no play and then give it a few more clicks to engage neutral easily. The clutch has never slipped since I fitted Barnett plates and a new clutch centre over 40,000 miles ago. I have printed out the clutch stack height info, and I'm going to pull the clutch next week and start measuring. The clutch isn't terribly heavy, quite manageable in fact, but I rode my mate's 750 Fastback a while ago and it was so light I thought the cable had snapped ! Time to do something.
Click to expand...

I recently had my clutch apart for a number of different "situations" and decided to work on the clutch pull. I don't like the idea of adding weight to the clutch, so instead of increasing stack height I put a shim under the circlip that holds the diaphragm and moved the diaphragm .020 closer to the stack. There was that much room in the slot. It made an immediate difference at the lever.
 
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