pauldalgarno Posted April 26, 2010 Report Share Posted April 26, 2010 Hi Folks, Looking for some guidance on my clutch (Beta Rev 3 250 cc 2005). Seems to drag even if I have the lever right out to give maximum leverage on the system. I've played about with the span and leverage point with no real success. I've done the clutch fix tagged on here and it's certainly made it smoother, but it still drags just enough when I'm in gear to have to hold it on the brake which causes issues on slower turns of course. Lever has plenty of feel, so I think it's working fine. I know it'll probably always drag slightly, but this is just enough to stall the engine even when the clutch is in. I'd prefer to have the lever closer to the bar for better control. What sort of travel is it possible to set it up for e.g. could it go from fully engaged to disengaged on approx 1 cm of lever travel at the end? Or what is possible with a perfect clutch set up? What is the wear limit for the clutch friction pads? Some looked like new, and some nearer both end of the shafts looked pretty worn - could this cause drag? Difficult to estimate, but would guess at around just under 1 mm on the friction material on the worst worn plates. Cheers, Paul Quote Link to comment Share on other sites More sharing options...
dan williams Posted April 26, 2010 Report Share Posted April 26, 2010 (edited) Hmmm, if you did the fix as outlined including the polishing of the tabs and removal of the excess glue then the only thing I can think of is warped plates or a weak throw from the actuation mechanism. It is possible for an older bike to have damaged or worn the return spring in the master cylinder on the bars. That might cause it to not return all the way and properly refill the system with fluid. Another possibility is wear in the clutch basket fixing the plates under load not allowing them to properly come apart. You didn't by any chance lose the ball bearing at the end of the actuator rod when you reassembled the clutch. Can you describe the drag better? Does it always drag from the moment of pulling in the clutch? Does it change? i.e. while you're holding in the clutch does the drag get progressivly worse over time? You could have air in the hydraulics. That would effectively reduce the clutch throw because air is compressible while the hydraulic fluid isn't (well it is, but to a much lesser degree). What are you using for tranny fluid? Two years in on my 08 and it still has NO drag. Sometimes I forget that it's in gear. Very entertaining to my friends. Edited April 26, 2010 by Dan Williams Quote Link to comment Share on other sites More sharing options...
pauldalgarno Posted April 26, 2010 Author Report Share Posted April 26, 2010 Hi Dan, thanks for taking the time to reply. In answer to your questions.. 1) Using Putoline SA75W GP10. Drained and new put in before last run. 2) Clutch drags whenever lever pulled in, doesn't change however long it's held in. 3) I've tried bleeding the clutch, but of there's air in there it must be very small and stuck somewhere in the system. Lever does feel meaty, so seems to be good pressure i.e. it doesn't feel like a soft brake lever. 4) Looking for an exploded diagram of clutch system to check where this bearing is at the moment. I peeled everything very carefully away, and didn't see anything. However it was dragging before, and the mods you put on here have made it more progressive, but not stopped or changed the drag. How much meat should be on the friction material? If the gap is too small between these pads will the clutch drag? The inner and outer pads were certainly significantly more owrn than the middle sets. I can check the plates on a glass surface for buckling. How far would the lever normally travel to disengage the clutch fully on a well set up bike? Quote Link to comment Share on other sites More sharing options...
pauldalgarno Posted April 26, 2010 Author Report Share Posted April 26, 2010 Hi again Dan, Found a diagram here http://www.trialsport.com.au/beta/Parts/Re..._270%202004.pdf Assume you mean part number 142 on page 2? I didn't have the clutch pump off, can the bearing fall out even without me being in that part? Cheers, Paul Quote Link to comment Share on other sites More sharing options...
nh014 Posted April 26, 2010 Report Share Posted April 26, 2010 Ensure that the thrust washer, item 90, part number 13-38360, in your parts diagram is in place between the inner and outer clutch baskets. Without it the clutch will drag. Quote Link to comment Share on other sites More sharing options...
duggan Posted April 27, 2010 Report Share Posted April 27, 2010 Have you tried bleeding the clutch in reverse? had a problem bleeding a clutch on my 09 evo, wouldnt bleed either way. after hours of struggling i noticed the small washer that holds the master cylinder seals in had been ever so slightly bent and was stopping the plunger returning fully. After fitting a new one the clutch reverse bled first time. Quote Link to comment Share on other sites More sharing options...
dan williams Posted April 28, 2010 Report Share Posted April 28, 2010 The uneven wear is a little disturbing. Could be a worn bearing or wear in the rubber bushing under the basket. I just measured a new plate across the pads with a caliper and get 2.74mm average. The aluminum base plate measures 1.70mm. Quote Link to comment Share on other sites More sharing options...
liviob Posted April 28, 2010 Report Share Posted April 28, 2010 Hello Paul. If you find that you have no warped clutch plates and all of the clutch parts are assembled correctly and working properly. You might have a look at the bearing that the clutch basket rides on. I had purchased a used bike a few years ago and no matter what parts i replaced. I could not make the clutch work properly. I had to replace the clutch basket because the outer race was not removable from the basket and the needle bearing that the basket rode on. After replacing these items my KTM 300's clutch worked fine. Quote Link to comment Share on other sites More sharing options...
pauldalgarno Posted April 28, 2010 Author Report Share Posted April 28, 2010 Thanks everyone! I'll check out the easy things first, then move to the things to check by dismantling, then the expensive stuff. Off into the garage for the night! Paul Quote Link to comment Share on other sites More sharing options...
liviob Posted April 28, 2010 Report Share Posted April 28, 2010 If the basket wobbles alot after removing the clutch plate stack you may have a worn clutch hub bearing. Quote Link to comment Share on other sites More sharing options...
pauldalgarno Posted April 29, 2010 Author Report Share Posted April 29, 2010 Hi Folks, Problem resolved when I backfilled the system. It forced some fluid back into the reservoir and it was dirty. Now changed the fluid by beeding new on top of old and clutch now OK. Will put the fluid on a 6 monthly replacement schedule. Also had a good look around all the other points to rule things out - plates are flat, all parts are present and correct, etc. Thanks for the advice all! Paul Quote Link to comment Share on other sites More sharing options...
ktminduro Posted August 3, 2018 Report Share Posted August 3, 2018 On 27/04/2010 at 5:38 PM, duggan said: Have you tried bleeding the clutch in reverse? had a problem bleeding a clutch on my 09 evo, wouldnt bleed either way. after hours of struggling i noticed the small washer that holds the master cylinder seals in had been ever so slightly bent and was stopping the plunger returning fully. After fitting a new one the clutch reverse bled first time. I had exactly the same problem on my Evo 200. Re-flatenned the washer with a hammer. I must have hit it too hard as i then had to file it down to fit back into the master cylinder. All good now. Quote Link to comment Share on other sites More sharing options...
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