jcr Posted July 3, 2008 Report Share Posted July 3, 2008 is there a way of adjusting the clutch on a 1999 txt 270 or is it a case of replacing the clutch plates? the clutch drags a little and it is difficult to engage neutral when the engine is running and fully warmed up,also what gearbox oil should i be using? Quote Link to comment Share on other sites More sharing options...
ridgrunr Posted July 3, 2008 Report Share Posted July 3, 2008 (edited) Try some Maxima 75 wt lite transmission fluid. Worked really well in the '99 321 and '00 280 GG's we had. Edited July 3, 2008 by Ridgrunr Quote Link to comment Share on other sites More sharing options...
steam Posted July 4, 2008 Report Share Posted July 4, 2008 I am about to replace the oil in a 97 270 with Dexron 3 as the bikes clutch is dragging. I will let you know if there is any improvement Quote Link to comment Share on other sites More sharing options...
jandyb Posted July 4, 2008 Report Share Posted July 4, 2008 I guess You will find some answers in this document http://www.trialspartsusa.com/diagrams/Clu...air%201990~.doc -Jan Quote Link to comment Share on other sites More sharing options...
jcr Posted July 4, 2008 Author Report Share Posted July 4, 2008 steam it will be good to know if the dextron 3 makes a diffrence keep us posted Quote Link to comment Share on other sites More sharing options...
peterb Posted July 4, 2008 Report Share Posted July 4, 2008 On the older GG motors, the clutch works best with either a mineral 10 weight, or an ATF rated to Dexron III, drain old oil when warm as any metallic particles are held in suspension and can exit the cases. Re-fill with 700ml. Finding neutral was never so easy on these bikes, but if you have excessive drag and it is not the oil, then you may have a problem with the clutch master, clutch slave or the clutch fibres have started to peel off the steel plates. The only adjustment you have is on the clutch lever. Bye, PeterB. Quote Link to comment Share on other sites More sharing options...
erikrs Posted July 10, 2008 Report Share Posted July 10, 2008 I just got myself a '99 txt 270 and have the same clutch drag problem. I asked the GasGas importer in Holland what oil to use and they advised a Putoline ATF. When I looked this up it proved to be a Dextron II spec. That's lucky since it's a GM spec and the same goed into the automatic gearbox of my Chevy van , so it was on the shelf. I cleaned the clutch-plates, changed the oil and the drag stayed I refreshed the hydraulic fluid and the drag stayed. Tonight I experimented with shimming the end pressure bearing and the result was that the "gripping-moment" changed accordingly, but the drag stayed Tomorrow I will check the flatness of the plates and if there is something amiss in the hydraulic system. I will keep you posted and if anybody has an idea where this problem comes from, I 'd love to hear it. It's not so that I don't want to invest in a fresh set of plates, but I'd like to know if they really are the problem, since I'm not convinced of that (they look brandnew, but measurements will have to confirm that). Is there anybody with a service manual that could give me the numbers to measure (clutch plate thickness/tolerances, traveling distance of the slave cilinder's piston a.s.o.). I've been trying already to get a service manual, but apparantly '99 is obsolete and not on the downloadlist of GasGas anymore Quote Link to comment Share on other sites More sharing options...
erikrs Posted July 11, 2008 Report Share Posted July 11, 2008 Well I'm back again and baffled. The clutchplates are flat, the fibre ones measure all evenly abt. 2.34 mm, spring lengths are equal, travel of the end housing is 1,5 mm, evenly spreaded (measured in 4 places). The master cilinder bore looks fine and the package is strong enough for the slave to bend open a forged Bessey clamp, without any feelable falling of the pressure. Still the drag stays I'm running out of ideas Next week I'll attend a workshop with a guy who has been running GG-bikes for quite a while. I'll talk to him, maybe he has an idea Well draggin' or not, I'm off to a little playground Quote Link to comment Share on other sites More sharing options...
peterb Posted July 12, 2008 Report Share Posted July 12, 2008 Hi Erik, Sometimes on the older GG motors, the clutch slave piston can give a problem: inside this piston is a ball bearing for the clutch push-rod to depress against. Over time, the push-rod can push the ball bearing farther into the piston housing to such an extent, that when the clutch lever is actuated, the slave piston is travelling as physically far as it can go, that is into the side of the crank case - this prevents the clutch plates from separating sufficiently. Over the years I have replaced 3 or 4 of these slave pistons which gave clutch drag symptoms, this may be your problem. The other thing to look at is to ensure that the ball bearing (another one) is still in place at the opposite end of the push-rod, separating it from the short mushroom headed push rod. If not, make sure it is not somewhere in the motor - lots of damage. You can still obtain the slave piston kit, or even a complete slave unit. I have never seen GG plates wear on the older bikes, only some that have had the clutch fibre rings peel away from the steel backing plate, have a close look for this as it is not always so evident at first glance. Bye, PeterB. Quote Link to comment Share on other sites More sharing options...
erikrs Posted July 12, 2008 Report Share Posted July 12, 2008 Hi Peter, Thanks for the reply. I'll check the slave cilinder. Needle bearing in the end housing is ok (I even tried shimming that a little bit). Plates are in perfect condition as mentioned, and would cause slipping instead of drag if they'd be worn. Hope to find the problem, since the bike runs nice and smoothly and this is the only thing that takes out the fun a bit I'll keep you posted Quote Link to comment Share on other sites More sharing options...
peterb Posted July 12, 2008 Report Share Posted July 12, 2008 Hi Erik, Just to make sure, the bearing I was referring to at the opposite end to the slave, is the single ball bearing that should be between the two clutch pushrods, not the end thrust needle roller. The fact that you tried shimming it out tends to indicate that there is insufficient travel - check for this single ball bearing aswell as the possible slave problem. Bye, PeterB. Quote Link to comment Share on other sites More sharing options...
erikrs Posted July 13, 2008 Report Share Posted July 13, 2008 (edited) Checked it all again: Ball between the 2 pushrods is present. There would be no pressure at all if that 's not there, I take it, since it's a 5 mm ball and the travel I measured is about 1,5 mm. The slave piston looks good and the ball inside dooesn't look to have moved (I see no marks at the piston at the counterside), but I must see if I can get hold of a new one to measure the distance from the flat side to the top of the ball (4,4 mm now). On the other hand, if that were the problem, shimming the thrust bearing should have had effect also. I will replace the piston's o-rings tomorrow, since one isn't so fresh anymore. I doubt that that is the problem, since there were no traces of leakage and I felt no loss of pressure testing it with the clamp. At least it's better when it's warm. I took the bike out last friday for abt. an hour and a half, so it really got warmed up and the dragging was less (but still present) then. To be continued Edited July 13, 2008 by ErikRS Quote Link to comment Share on other sites More sharing options...
jse Posted July 13, 2008 Report Share Posted July 13, 2008 (edited) The slave piston looks good and the ball inside dooesn't look to have moved (I see no marks at the piston at the counterside), but I must see if I can get hold of a new one to measure the distance from the flat side to the top of the ball (4,4 mm now). Erik, I got a new piston kit out of my parts and measured the distance (the ball is installed with the piston when manufactured) and it was 4.5mm from top of ball to flat of the piston. Jon Forgot to mention. Although it's only a wild guess, I'm thinking that perhaps a slight amount of drag is designed into the clutch pack. Just about all the GasGas bikes I've known for over a decade have had a least a slight amount of drag and I would think a company with their experience could make a full-release clutch if they wanted to. It makes finding neutral when stopped a pain but watch bikes in a full-lock tight, slow turn and where you will see some other bikes with full-release clutches crabbing the front tire over the tape, but with the driveline always "loaded", the GasGas seems to be easier to control. Like I say, this is a wild guess based on observation. Edited July 13, 2008 by JSE Quote Link to comment Share on other sites More sharing options...
erikrs Posted July 13, 2008 Report Share Posted July 13, 2008 (edited) Cheers Jon, I'll speak to some more GG-riders in the near future to see what their opinion is on your theory. I'm not completely unskilled in spannering and mechanics and have found everything in order as for now. And it's not a very complicated system First I'll do some more riding now Edited July 13, 2008 by ErikRS Quote Link to comment Share on other sites More sharing options...
erikrs Posted July 22, 2008 Report Share Posted July 22, 2008 ...Next week I'll attend a workshop with a guy who has been running GG-bikes for quite a while. I'll talk to him, maybe he has an idea.. Well I spoke to the guy of the trialdemoteam last sunday. Apparently the problem is lateral play on the clutch housing, so the platepackage doesn't move enough, since the housing is partly moving with it. As a practical solution they usually stack 3 metal- and then 3 fibrecoated-plates in the pack, instead of the normal procedure (1 metal, 1 fibre a.s.o.). The other solution being of course getting rid of the play, but that's a more serious operation. I will try this trick and let you know the outcome. I just started, but this trial virus is really on me now, so I will, without doubt, know all the ins and outs of the bike in a short time. But before my next ride I will first go out and buy some proper gear, especially boots, since I already hurt my leg badly slipping of the kickstarter in the rain Jumped my first pipe though (on my second time on a trial's bike). Me happy Quote Link to comment Share on other sites More sharing options...
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