hello all. what is the minimum thickness of the fiber plates? (748 but same as ...) is there one? was having probs with the clutch, pull in lever and the bike keeps moving.. pulled it apart a few weeks back and there looked to be very little meat left on the fibers, done no more than wheel it to the back of the shed (as i assumed that was the prob) untill today i thought id put the 749 clutch in it, (well i thought about it last week but didnt action it till today) anyhu, the fibers on the 49 look as worn and its working fine so i measured both.. 2.9 mm on average. some of the plates further down the stack were stuck together on the 48 so i sanded the steels, cleaned fibers and reassembled.. she's all good so far..
shit... on the limit then... mind you theres a few of em so i may have a mm to go combined! how do ya measure the .2 outa flatness?
the flattest surface i have is the kitchen worktop and being a single man the flatness varies depending on the expectancy of company... that and i installed the worktop and it aint flat to that degree.. (or level)
Most folk won't have a surface plate handy. I have a sheet of plate glass off the front of an old (1960's) telly that I use for this sort of thing. You should be able to find something suitable, big enough to place a clutch plate on.
Not sure quite where you are exactly with this. You say that some plates were stuck together and you've unstuck them and sanded the steels and she's all good so far. Does that mean you are no longer getting clutch drag and are just asking about the minimum thickness or is the drag still there????
no longer having issues... but there is fuck all meat left on the fibers (about half a mm to the eye before it hits steel)
Well, it's up to you if you ignore it till it slips or replace now. However, when you replace the frictions, you're likely to get some drag at first because the new sharp tabs tend to bind in the old basket slots, which will have some degree of notches in them. If your frictions are that worn, are you not getting terminal chatter??
not really.. its a bit noisier than normal id say but other than that ,untill the issue the other day no probs at all... no signs of wear on the basket (its a stock 1098 item with 5000 miles in total on it) as i said the plates in the 749 are at 2.9 mm as well and are functioning fine.. but i do have the feeling im in for new fibers on both real soon.. any recommendations on brand of?
Leave them until they start to slip. I got 38,000 out of the plates only ST4s, albeit after the quite clutch mod.
the worrying thing is ive only got 5k outa the 748 with a near as new clutch outta a 1098 engine. im talkin that engine has 200 miles on it and plates and basket looked as new..
The plates have little meat on them when new. It is normal with these bikes to have to change the plates due to knackered tabs long before the friction material is worn out. Usual scenario is that the tabs chatter within the basket slots and create wear, the slots get notches bashed in them and the tabs get hammered smaller and fatter. As this happens, so the chattering gets amplified in a vicious circle until the clutch is not just chattering at idle, it also chatters on a neutral throttle when riding along. It is at this point that most people decide to renew their plates and often the basket too. However, although the tabs are knackered and the basket slots are notched, there is usually plenty of life left in the friction surfaces themselves, as evidenced by Derek's 38,000 miles out of one set. Derek says that this is due to his use of the quiet clutch mod. I too have done this and thoroughly recommend it, as the elimination of chattering/oscillation virtually eliminates wear between tabs and basket and your almost pristine basket will stay that way for tens of thousands of miles.
My 998 when it was new did less than 1,000 miles before the centre plates in the clutch pack were completely worn through to the metal. They were replaced under warranty as there was clearly some sort of production fault with them. Having said that even new or decent clutch plates can wear rapidly and it seems to vary between one clutch and another, steel ones seemingly being the worst. I now use alloy plates in an alloy basket as they seem to work better as a set. If you want to run with the friction plates on the limit I would suggest you check the clutch pack regularly for potentially severe and quicker wear as they get near the limit. I always try and run mine to the stated limit and then replace them, not all at once though as I just put a few in let them bed down and then build up to doing the rest after the new ones have settled. Alloy plates in a steel basket also can give the basket an easier life but steel baskets really do ring like a bell as they get older and more worn.
Derek gets 38.000 miles and you get less than one thousand?? Wow... Are you doing loads of full-power launches or sitting at traffic lights in gear perhaps? Can't understand why you'd get such heavy wear. Maybe the plates were faulty as you suggest and the friction material broke up and became detached. Good idea to replace the plates a few at a time. I've done that and put the new ones at the bottom of the stack, so the old, looser ones are at the top and allow the clutch to clear nicely. As you say, an alloy basket and alloy plates are the way to go, if only to lose some of the rotating mass.
Neither as I was running the bike in and it was discovered at the service. It was one of a few teething problems I had when the bike was new including a rocker gallery oil leak, the clutch and the some minor wiring problems. Pretty poor for a new bike really although not atypical and all was fixed under warranty. Since then it has been fine and I now run a Sigma Performance slipper clutch which seems to be a little better on the plates overall.
