Ok so I had this knarley crash the other week. The bike was basically suspended by the shift lever when it was all said and done. After wards I noticed that it would not shift down easily and it would only catch every 5th or 6th time. It would shift up fine and it would return back to center spring loaded. 90% of the people i talked to said that my sheer pin shift shaft end was broken. I thought that this would cause my shifter to just free rotate 360 degrees... Well i ordered the sheer pin assembly and thats not it. Something is popped inside of the case... My buddy who has a puller for a gasgas is not going to be around till tomorrow so i am stuck with my brain wondering whats the root cause. Thoughts? Experience?

--Biff

At a guess I would say a bent or out of place shifting fork. Before that though there should be a small screw inside the clutch/flywheel cover, can't remember which as I have only stripped down a beta and not sure if its all opposite.

This may need adjusting slightly till you get a positive click in both directions, if you cant obtain a positive click in both I would reccomend checking your gearbox internals. Split the cases and you'll see which side there on, check these are all posistioned securely and none are snapped... Check it all out and get back to us! If you go on youtube with 30 mins spare and check the engine strip down videos (all three) In one of which it shows the adjuster screw, if this doesn't work it shows the full strip down procedure(sp?)

Best of luck,

Jamie

Edit: lean the bike on its side to adjust the screw, saves draining the fluid for something simple... thats if it is that!

Edited March 21, 200917 yr by shercoman2k8

Hi Biff,

As shercoman said earlier, try the shift spring stop eccentric adjuster to see if you can get all of the gears with your new sheer pin (The spring with top hat looking shouldered washer with a pin across it).

If not, then it is very likely to be just a shift fork or two, the older PRO's had shift forks that you could position back to back to check if the forks were parallel, later ones look more beefy and don't allow this visual check, pity as now it becomes difficult to tell which one or two is/are bent - look for suspicuous looking rub marks on the ends of the forks.

You'll need a flywheel puller, leave the head on the barrel and remove as one unit, maybe a puller for the crank gear though if you do this right, you can leave it in place and try to split the cases leaving the gears and crankshaft in the RHS case, you can get away with leaving the k'start shaft in place but I find it better to remove it, don't lose the washer between the k'start shaft and the clutch case, leave the hydraulic connection on the clutch case, should take about an hour or so. Need a new c'case gasket and clutch gskt - check the c'case seals!

Bye, Peter.

Hi Biff,

As shercoman said earlier, try the shift spring stop eccentric adjuster to see if you can get all of the gears with your new sheer pin (The spring with top hat looking shouldered washer with a pin across it).

If not, then it is very likely to be just a shift fork or two, the older PRO's had shift forks that you could position back to back to check if the forks were parallel, later ones look more beefy and don't allow this visual check, pity as now it becomes difficult to tell which one or two is/are bent - look for suspicuous looking rub marks on the ends of the forks.

You'll need a flywheel puller, leave the head on the barrel and remove as one unit, maybe a puller for the crank gear though if you do this right, you can leave it in place and try to split the cases leaving the gears and crankshaft in the RHS case, you can get away with leaving the k'start shaft in place but I find it better to remove it, don't lose the washer between the k'start shaft and the clutch case, leave the hydraulic connection on the clutch case, should take about an hour or so. Need a new c'case gasket and clutch gskt - check the c'case seals!

Bye, Peter.

Biff is now out of TT days! Oh Crap!

I don't even want to know how you got that bike in that position!

The ratchet arm assembly (part of the shift shaft - under the drum) can get bent easily as well. check it out when you have it apart.

Ok got her apart last night and the winner is!!!!

Laser1 you called it...!!!! <damn that's good

Cope.... It was one of those hmmm i don't think i need that much throttle..... Oh cra....

One of the two ratchet arms was not only bent but it cracked off the little ear....

First thought from me is.... Ooooo damn that looks expensive... Alas! Another Michigan gasgas rider had a shift shaft. Back in business baby! HA!

Here are some pictures of the breakage.

Thanks again guys!

--Biff

Hi Biff - Sorry to hear it, Unfortunately, Ive seen it several times. Ive also found as the previous posters mentioned, the forks can get tweaked as well when theres that much force involved. If your forks are also damaged, make sure you get the latest type shift forks (they made some recent improvements) . One nice feature about the pro tranny, you can test it out while its open. Also - you probably know, there is a trialspartsusa video on how to adjust the shift shaft eccentric. I make certin to check the up/down from 1st to 2nd and also 3rd/4th. I find it usually takes me several attempts before I get it set right.

Best of luck with it

YEA!!!!! Biff can come out and play a week from Saturday!!!!!!!