I`ve just bought some stainless clutch springs to use with my standard pressure plate and spring caps. These springs are 1mm shorter than the standard ones, the clutch will only work if I put a 1mm washer under each spring cap. Would it be ok to run like this? Anyone else had to do the same? Everything will be tightened, nothing will be left loose. I am going to ring the seller in the morning to double check he has sent the right springs for my bike. Cheers.
it shouldnt make much difference about 1mm should it? Theyre under compression so if theyre not too short it wouldnt matter? I may be wrong though
I bought some cnc clutch springs a few months ago, along with a new pressure plate.....and they are a lot shorter than my standard springs. The new plate fits closer than the standard ( according to my mate who fitted it). Hope this helps.
that's often the only cure for some aftermarket springs as they become coilbound before they can produce even 2mm of compression when fitted (which is madness really). I would send them back personally but it's perfectly acceptable to use them with an added washer imo. Apart from this, the main thing to check is that the actual spring rate isn't higher than the standard fitment springs as aftermarket st/steel often are. If you don't object to a higher effort needed at the clutch lever then please ignore the last bit.
Thanks all. I spoke to the seller today and he said the springs should be ok with oem caps. He also said they would give a similar weight to the standard springs, +/-5%. The clutch works fine with a small washer under each cap. When I stripped the clutch I found I have a 39mm stack height, and its had an extra friction plate (3mm thick) put in first, this will be why the clutch is so quiet. Would I be right in thinking this makes for a 42mm stack height, or isn`t it as simple as that? The clutch has been like this since I bought the bike, no drag, no slip, no squealing and no trouble finding neutral, also, cos I`m a leftie, I don`t find the clutch particularly heavy to use.
It isn't as simple as that because the plain plate that normally goes in first has tangs that fit in a slot with a square end at the bottom. If you put a friction plate in first, it sits down further because the tangs on a friction plate sit in a deeper slot with a rounded end at the bottom. This is what makes the clutch quieter because the friction plate jams into the bottom of the curved-bottom slots, damping the movement of the stack and preventing it from oscillating backwards and forwards. This has the added bonus of reducing wear on both tangs and slots, which is usually what causes the plates to need replacing, long before the friction material is worn down.
Thinking about this further, I realise I didn't give you a full answer to the original question. Because the first plate now sits further down than the plain plate did when it was the first plate, I guess what now matters is the effective stack height, not the total stack height. Some people have found that they can fit two friction plates below the first plain plate and end up with a similar effective stack height. I could only fit one. What I find really strange is that a friend of mine, who has restored a 900SS, is that he has simply re-ordered his plates with a friction plate at the bottom. You'd think this would make his effective stack height too low but he swears it's absolutely fine...
