I stripped my single spring clutch yesterday and found that the steel plates had some light rust on them, about 50% of the surface area. No deep pitting. I was able to separate the fiber discs (with 'Ferodo' marked on them) from them with ease after using some petrol on them.
Before I scrap the steel discs, I thought I'd better ask if I can (1) wire wheel the steel discs clean and reuse them, and (2) if the rust will have damaged the fiber discs.
Rather than scrap the lot and then wait two weeks for spares to arrive I thought I'd ask advice first.
If nothing is too worn and pitted, I would give the plain plates a rub down with wire wool on a flat surface, wash both plates (fibre and plain) in petrol and put it all back together.
In the meantime I would probably order a full set (plain and fibre plates) and keep them as back up if the clutch is playing up after using the old plates.
Thanks for this, Pat -- I was beginning to think the same way myself. I think I'll take your advice.
I noticed when I took the clutch apart that the center nut was poorly made, and in fact tended to bind up on the center thread, removing shards of steel from the nut's threads. This one's clearly one of the ones Draganfly warns us against as being from a faulty production run of 'a major manufacturer'. I can't work out how they got it wrong - the threads seem to get tighter towards the middle, but are fine at each end. I don't know how a tap could do that....
M20's share their clutches with a lot of much more powerful engines so you can do a lot of naughty things with them
For 15 years I have run with doubled steel plates and one less set of plates which I have found works very well
Me too. Both mine are more powerful than a standard M20 and I've run for years with one steel and one friction plate removed. Gives a lighter clutch and more room for the plates to separate. Ron
It's helpful to know that these clutches are so robust. I will remove one steel plate and one fiber plate when I rebuild it (pending the arrival of the new Draganfly center nut). The steel plates are cleaning up pretty well, and the fiber ones seem brand new, at a healthy 3/32 thickness and no signs of wear. The faulty center nut meant that the spring was never fully tightened down - and with the plates stuck together with light rust I could neither get them to separate nor to transmit full power. The worst of all worlds! It's amazing I could go down the road at all....
Just ready your reply to this thread and was wondering if you could recommend a manufacturer or supplies of the clutch plates you are using. I have found that sometimes when I'm sitting at lights with the clutch pulled in all of a sudden the bike is pulling itself forwards, I cannot hold it back I need to step on the rear brake peddle. It seams to happen if I tip the bike over to the right while I'm sitting there. I presume one less plate would give me a little more space, But I may just go ahead and change to a new set while I'm at it.
Could it be Stuart, that the clutch is not straight inside ?
I've heard the spring is sometimes slightly bent. Not allowing to free the plates completely.
Stuart, after market friction discs can often be thicker than standard and can be the reason for clutch drag, especially when the clutch gets hot, even more reason to remove two plates. Best to strip and inspect/measure them. No point replacing them unless you have to.
Ian wright had several sets manufactured to the original spec, but I don't think he has any left?? I still have a spare set of Ian's in stock for my own bikes. Otherwise it's Russell's, Draganfly or C&D Autos I guess. Ron