user7743 Posted April 21, 2018 Report Share Posted April 21, 2018 Hi all, I have a (new to me) Beta Evo 250 from 2010. Had it for a couple of months and given the clutch was sticky I did the clutch mod. That solved the cold drag. Fast forward a few weeks and two things have happened. Firstly, I did an oil change last week and put in some Motul Transoil 10W30. Secondly, the weather has upped its game from hardly above 0 the first few times i rode, to 25+ today. After everything got nice and hot, the clutch got to slipping like mad; to the point that I couldn't pull up bigger hills nor loft the wheel with the clutch or power alone... Just a bag full of slip. I guess my questions, anyone have experience of Motul's Transoil in a Beta? Is that likely be the crux of my issues? I felt the oil was low when I changed it, as it was barley visible in the sight glass when warm. After my change it is a per manual, always visible (when upright) both from hot and cold. Is too much oil going to be giving me issues? Or is it that I have just found a weak point of the bike that was there before but given the cold wasnt showing itself? Hopefully you can point me in the right direction before I go trying loads of different things and getting nowhere... Thanks in advance! Quote Link to comment Share on other sites More sharing options...
dan williams Posted April 21, 2018 Report Share Posted April 21, 2018 Did you do the tab polish part of the mod? The steels can get polished after a while and can use a dressing with fine emory cloth to break up the surface glaze. Do you have enough play in the master cylinder for the piston to return all the way opening the reservoir port? If not pressure will build up in the hydraulics and cause slip. Most people seem to run a little less than a full gearbox as it seems to cause a bit of drag. Quote Link to comment Share on other sites More sharing options...
user7743 Posted April 22, 2018 Author Report Share Posted April 22, 2018 Hi Dan, Yes, I performed the tab polish as well as clearing the glue from between the friction pads. The cold clutch drag beforehand was mega - the bike would basically run away as soon as you engaged a gear. After the mod, just a more familiar "clunk" on engagement. When you say steels - do you refer to the plain steel rings between the friction rings? Master cylinder play should be okay - it hasn't been changed since I initially set the bike up for me, but I am fairly confident there is plenty of free play there. What would be strange to me is why this issue hadn't manifested itself before it it was down to free play. I let a bit of oil out when I can back yesterday so it is lower in the sight glass, but I wont get to try this until next weekend as I am away for the week. To me it seems to be the kind of problem you hear of where the wrong oil is used on a street bike and causes clutch slip when the oil is warmed and less viscous. Hence my question to the specific Motul oil. Quote Link to comment Share on other sites More sharing options...
section swept Posted April 22, 2018 Report Share Posted April 22, 2018 Dump the Motul Transoil and use Putoline GP10 as per Mr. Lamkins suggestion. Maybe also a second look at the clutch to ensure all is well rebuild wise? Quote Link to comment Share on other sites More sharing options...
user7743 Posted April 22, 2018 Author Report Share Posted April 22, 2018 (edited) I assume when it comes to the Putoilne GP10, the SAE75 rating is okay for a Beta clutch? I'll order some and hopefully it will be there when I get back at the end of the week and I can give it a bash. Edited April 22, 2018 by user7743 Quote Link to comment Share on other sites More sharing options...
dan williams Posted April 29, 2018 Report Share Posted April 29, 2018 So how did you make out with this? Quote Link to comment Share on other sites More sharing options...
user7743 Posted April 29, 2018 Author Report Share Posted April 29, 2018 6 hours ago, dan williams said: So how did you make out with this? So far so good. Ordered the Putoline whilst I was travelling and it arrived Friday afternoon. Yesterday I managed to get an hour and drop the Motul and put the fresh Putoline in. I didn't get much more than an hour riding in, but so far so good. I should get some more time today (and the ambient temp is forecast for 25°) so it should be a good test. That said, I'm hopefully based on yesterdays limited test (I've not been riding trials for long so thee finer feel of things isn't yet there). One thing is for sure, no more Motul Transoil for me ? Quote Link to comment Share on other sites More sharing options...
user7743 Posted April 29, 2018 Author Report Share Posted April 29, 2018 9 hours ago, user7743 said: So far so good. Ordered the Putoline whilst I was travelling and it arrived Friday afternoon. Yesterday I managed to get an hour and drop the Motul and put the fresh Putoline in. I didn't get much more than an hour riding in, but so far so good. I should get some more time today (and the ambient temp is forecast for 25°) so it should be a good test. That said, I'm hopefully based on yesterdays limited test (I've not been riding trials for long so thee finer feel of things isn't yet there). One thing is for sure, no more Motul Transoil for me ? Unfortunately it hasn't solved the issue... It seemed to hold out longer (or I was riding lighter because of the warmth ;-) ) but after a while I did start to slip again. What would you look at next? Roughing up the steel plates a little? If so what grade of emery cloth would you use? I would also look to measuring the friction plates whilst having it open and see how much they have on them. Anything else to look at to get to the bottom of this one? Thanks for the help so far! Quote Link to comment Share on other sites More sharing options...
dan williams Posted May 1, 2018 Report Share Posted May 1, 2018 It usually takes a couple of oil changes to get completely rid of wonky oil so you may be in for more work. I’m kind of surprised though as the motul is spec’d for wet clutch. Then again most bikes don’t have trials clutches. We are a bit weird in how we use the thing. Quote Link to comment Share on other sites More sharing options...
user7743 Posted May 1, 2018 Author Report Share Posted May 1, 2018 7 hours ago, dan williams said: It usually takes a couple of oil changes to get completely rid of wonky oil so you may be in for more work. I’m kind of surprised though as the motul is spec’d for wet clutch. Then again most bikes don’t have trials clutches. We are a bit weird in how we use the thing. To be fair, it could well be that the issue was there before with the original oil, but not manifesting itself given the lower temps when I bought to the bike. I am going to check the fingers on the friction plates to make sure I really have flattened them off and also measure the thickness. See where that takes me. If this doesn't rectify, I think I jump straight to ordering a new set of friction plates. Its probably cheaper in the long run when taking the man hours into account ;-) Quote Link to comment Share on other sites More sharing options...
trapezeartist Posted May 1, 2018 Report Share Posted May 1, 2018 Check the springs too. If by some strange occurrence they are short, they won't be applying the necessary clamping force. Quote Link to comment Share on other sites More sharing options...
user7743 Posted May 1, 2018 Author Report Share Posted May 1, 2018 1 hour ago, trapezeartist said: Check the springs too. If by some strange occurrence they are short, they won't be applying the necessary clamping force. Will do. Any idea what spec they should be? I cant see anything in the manual. I have been out and smoothed the fingers on the friction plates and measured the material. Anyone know the minimum thickness? I am sure I have read it somewhere but I cannot find it for the life of me. The friction plates come out with the following thicknesses in mm: Plate 1: 2.72 to 2.84 Plate 2: 2.68 - 2.72 Plate 3: 2.69 - 2.72 Plate 4: 2.70 - 2.73 Plate 5: 2.69 - 2.72 Plate 6: 2.70 - 2.73 After lunch, back out to put it all back together. 1 Quote Link to comment Share on other sites More sharing options...
dan williams Posted May 1, 2018 Report Share Posted May 1, 2018 These are pretty much what they read new. I have yet to see significant wear on Beta clutch plates. Nominal is 2.7mm with the two thicker plates used in the newer bikes at 3mm. Quote Link to comment Share on other sites More sharing options...
dan williams Posted May 1, 2018 Report Share Posted May 1, 2018 Thinking about it the previous owner could have put some funky oil in with friction reducers. You never get all the oil out unless you split the cases. If it got better with one fill then it may get better with more flush and fill. I don’t normally recommend ATF as I find it makes for a grabby clutch but it’s cheap and maybe just the thing to get you through a couple oil chages. Quote Link to comment Share on other sites More sharing options...
user7743 Posted May 1, 2018 Author Report Share Posted May 1, 2018 Cheers Dan. And just for reference - springs were measured at 32.95 and 33.49mm in length between the 6. I am going to go out and see if I can test it now and see how things go. Temps are lower today so will be a decent test to see how long things "hold" for and if I get slip. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.