dan williams Posted July 22, 2009 Report Share Posted July 22, 2009 To the best of my knowledge that is the only significant difference with Sureflex and what got me started on this issue. The 30X series of Fantics came with Sureflex plates and their clutches were excellent. Quote Link to comment Share on other sites More sharing options...
mrkartoom Posted July 22, 2009 Report Share Posted July 22, 2009 To the best of my knowledge that is the only significant difference with Sureflex and what got me started on this issue. The 30X series of Fantics came with Sureflex plates and their clutches were excellent.I'll be sure to go with them when replacing mine. I assume they are cheaper than the stock units anyway. Quote Link to comment Share on other sites More sharing options...
yeoblade Posted November 19, 2009 Report Share Posted November 19, 2009 Had the same clutch not dissenaging problem, carried out all of the above, and now its clearing fine, thanks all the info, wet n' dry on plates, cleaning edges and AFT. A couple of problems I came across were: a) I only took off the circular cover, 4 bolts, to get to the clutch plates, this seemed sufficient, because, After removing the kick start bolt I could not get the kick start off, does it just pull off? tried wedging it off with screwdriver against case but wouldn't budge, stopped before I damaged casing, so couldn't get the full cover off. TIA Julian rev3 250 2002 Quote Link to comment Share on other sites More sharing options...
nh014 Posted November 21, 2009 Report Share Posted November 21, 2009 It's been mentioned before but if you want to eliminate clutch drag on a Beta Rev 3, deglaze the clutch plates, and if you know someone who can do it, have the metal plates knurled. To deglaze the friction plates place a piece of 150 grit paper on a piece of glass or some other flat surface and lightly rub the friction plates over the sandpaper in a figure 8 pattern. Roughen them up just enough to take the glaze (shine) off them. Of course replace any warped plate. Deglazing every 5 or 6 events will ensure that you can find neutral with the engine running. Using ATF oil will also help reduce drag, but it tends to make the clutch a bit grabby. Quote Link to comment Share on other sites More sharing options...
jokerr Posted November 23, 2009 Report Share Posted November 23, 2009 Take a jeweler's file or an ignition file and remove the adhesive between the fiber pads on the fiber plates. Then look at the tabs on the fiber plates that ride in the grooves in the clutch basket. These are usually unfinished and are the cause of most of the Beta clutch problems. Essentially these are bearing surfaces and when the clutch must engage or disengage these have to slide in the groove of the clutch basket. This is what the plates look like from the factory. http://newenglandtrials.org/clutch001.jpg http://newenglandtrials.org/clutch003.jpg Needless to say this is less then ideal as a sliding surface. Imagine as the clutch is engaged these surfaces are torqued against the side of the clutch basket grooves and stick. This makes the clutch slip until the lever is released further and the plates let loose with a snap. AKA light switch clutch. Also why the Beta seems to have a heavy clutch. The heavy springs are there to compensate for the inability of the fiber plates to slide by forcing them into position. Now look at it from the disengagement side. The lever is pulled in but the plates are held in place by the torque forcing the rough surfaces on the tabs into the basket grooves not allowing the plates to slide apart to release the clutch. This is the famous Beta dragging clutch. Take a fine file and smooth the sides of the fiber plate tabs trying to keep them even with each other so they all contact the bearing surfaces of the clutch basket. This removes the rough edges. Finish with a polishing stone. It's OK if it rounds them somewhat. I've done this on several bikes and the result is a Beta clutch that is smooth and consistant. One of these days I have to write up a good description of the procedure but for now this will have to do. On my bike with the fiber plates cleaned up and two springs removed I have no slip and a light clutch pull that is on par with any bike I've ever ridden. It's a time consuming fix to do but it's free and it works like a charm. dan i tried to send you a pm but dont know if it worked. so here goes i have a 2010 evo 250 2t the clutch operates fine other than the bike will not roll freely when in gear, running or not, hot or cold . selecting neutral when running is also very difficult. neither of these issues are a show stopper for me ( dealer is 6 hour round trip away) but i would like to lighten the lever pull by removing 2 clutch springs . is this as easy as removing casing remove 2 bolts and springs? or does the whole clutch have to come out? if so i would consider carrying out your developed procedure on tabs and plates. does the whole clutch come out by removing the 6 spring retaining bolts? many thanks in advance jokerr. Quote Link to comment Share on other sites More sharing options...
dan williams Posted November 29, 2009 Report Share Posted November 29, 2009 (edited) Sorry I didn't get to this earlier. Busy at work and then flu. The heavy springs are there to compensate for the friction of the rough fiber plate tabs. If you just pull two springs without doing the whole procedure you will end up with a worse performing clutch, with a light pull. It works on the EVO. I'm currently giving the treatment to a set of plates for one of the top New England riders. He's ordered his 2010. I worked on the plates for his '09 EVO and after the last event this year he handed me a spare set of plates to put in the 2010. He was amazed at how good the clutch was especially when he saw his competitors fighting with their grabby, dragging clutches. He doesn't talk about the modded clutch though. I don't think he wants to give up any advantage. Oh yeah. Finding neutral on a Beta even with the modded clutch...good luck. Not really on topic but why do trials bikes shift so clunky compared to Japanese trail bikes of the '70s? I've head lots of explanations but the one that makes the most sense to me is that they use two shafts in the transmission instead of three to save weight and space and that makes it much less mechanically simple to shift gears. Edited November 29, 2009 by Dan Williams Quote Link to comment Share on other sites More sharing options...
jokerr Posted November 29, 2009 Report Share Posted November 29, 2009 thanks dan, i will probably give it a go when the weather is a little better (garage is freezing) untill then i will try an alternative oil, currently using "silkolene light gear" it was the only thing they had at our local shop. i was considering atf but your comments on jerky take up have me reconsidering. cheers . Quote Link to comment Share on other sites More sharing options...
dan williams Posted December 1, 2009 Report Share Posted December 1, 2009 Since I'm doing a set now I suppose it's time for me to drag out the camera and document the procedure. Will post in a few days. Really. Quote Link to comment Share on other sites More sharing options...
matt_urban Posted December 2, 2009 Report Share Posted December 2, 2009 i just did my bike al it was was the friction plates needed a scuff up with sand paper and bam work fine now from cold I think its worth doing when it starts to drag the glazing makes the plates stick together Quote Link to comment Share on other sites More sharing options...
dan williams Posted December 5, 2009 Report Share Posted December 5, 2009 That will work for a short time but it isn't the solution. I did that before but it never lasts. The treatment of the fiber plates I do only needs to be done once to last the life of the clutch pack. I shot the pictures of the mod and will try to have them and the description up this weekend. Quote Link to comment Share on other sites More sharing options...
matt_urban Posted December 11, 2009 Report Share Posted December 11, 2009 I did the same on my bike scuffed plates up and clutch friction plates works good now i can start it in gear no problems Quote Link to comment Share on other sites More sharing options...
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