lineaway

That`s long ago now, Maybe 2013.

We had a member replace the whole transmission at 7 months. I want to say it was a 2012. Always something with the Pro motor. Great motor when it is running!

My son actually broke 2 gears in my front yard. He endo'ed over the bars. When the bike hit the ground the rear sprocket hit a brick that he had been using as a kicker. The engine was sill turning, knocked the chain off and wrapped around the front sprocket. One we got the chain off, we realized the tranny was locked solid. The next day which was a Sunday morning, when I split the cases 2 broken gears fell out. Monday I overnigjted the parts and wednesday I got the bike back together after work. We left Thursday for a 2 day event and my wife bought him a new bike on Friday! That should have been our last Gasser. I now have 2 more for my grandsons!

I guess you never read through the gas gas forum. Ever since the pro motor came out in 2002 it has been the most defective transmission in modern motorcycle history. So much so they changed the cases to where you could fix the tranny without splittinv the cases. Usually its the kickstart gear or the shift shaft breaks inside the drum. You are just unlucky. Good luck.

I had just assembled a brand new 1995 Fantic section that would not shift at all. After a couple of days of checking the easy stuff I split the motor. I found nothing wrong at all but a blued shift fork from forcing the shift. (Side note, it was assembled without a base gasket from the factory. Plus for the tear down.) Replaced all the shift forks and reassembled. That bike never, ever had another mechanical problem. Just goes to show not all issues are clearly evident. You might fake putting the cases together to get that motor to shift through the gears before the final re - assembly. Good luck.

The shift shaft would break loose at the weld. You did check that?

You do know that you have to spin the shafts to get them to shift.

Did you have a shift shaft problem first?

Well you are correct on that stock it is lean. All the bikes stock come lean from the factory. The Gas Gas forum had a lot of that info. It all depends where you are from as the fuels can be different. Seems in the .U.K. they were big on changing the slides on the pwk. But I think they also showed a different needle. In the states we usually just increase the pilot size, but our fuel is different and we ride higher elevations. Hopefully someone replies with a thought on the needle.

Working on hydraulics all the time, that is the preffered method. THE HAMMER. I always loosen all the large parts before removing the top end so you can hold it all in place. Makes life much easier. Same going back together.

You don't have an air impact or electric. Is the clutch side still togethet that you could hold the crank from turning by the rear sprocket. All tbis should have been done before engine tear down.

Yes.

The 4t is a fairly new motor. Should be right hand thread. A little hard with the motor apart.

The water pump impellor should have nothing to do with the head/ cylinder coming off. To be honest I never had to rebuild the 4 stroke beta thank god. We now ride Montesa.

https://www.ebay.co.uk/itm/116330877076?_skw=montesa+mh200+piston&itmmeta=01JCBJ8VY26YT4V0JAA595ZDTP&hash=item1b15dc5094:g:dAwAAOSwcCFm6vXm&itmprp=enc%3AAQAJAAAA0HoV3kP08IDx%2BKZ9MfhVJKkrnTzj2UbGziiRkQuuQYBoWIpbixYVJNUYrAa9JJbJtXtz2EWUiC5EyVVmsEUnfzjV1ofs50DSh7gRa0mQfgbYp1o5YBejKoHIbOgksb%2Bj8t4Td1hlI6NOECjNbW64rCXbHfD1zr0kS1FuPWodl1rXQxxw3O%2BxcrZONAnmtBq8mLaBci%2FWXCH7QbwXUy6A3R%2F3KKtxT0Sk0TQyUJMioT8UGhtv%2B4dkhm9l1j2Ka%2FFJ9tPus59qNSbxQWKHoo88nSU%3D|tkp%3ABk9SR46_o_LiZA

The coil is 30500-ML7-013.

Was it the coil or the assembly? Mind sharing which part number?

I started riding Beta in 1990. And still to this day Atf works the best. You can get it anywhere and its cheap. So change it often. TOTTY79 is correct that motul and other brands are more progressive, but that is not what you need in a trials clutch.

Being a Pro model. Anything is possible to be wrong inside. You are right wanting to fix it. A new transmission has to be quite expensive by now, or not available at all. I would pull it apart before any more damage happens.

Yes and no. The shifter can keep working with the tab sheared. But you are correct about a complete shift shaft. P.O.S.

If you look at that video. The shifter spring is held together by a piece of metal known as the top hat. There is a tab on it that can break and cause movement. You buy it complete with the spring. If that`s not the problem then one of the parts within the shift drum has broke. Which requires the cases to be split.

There is one on the u.s. Ebay right now. 165. With shipping. About 5 years ago they found a few hundred left overs that sold for 20 each.

Are you sure it's not a Grimeca master cylinder. Are you asking a dealer or just browsing the web. S-3 digit levers are easily available for Grimeca.

Maybe a 2001. Is the air box on the left side?

The 250/260 were very easy to keep running. My son has a 2018 300rr which has required very little attention. My 2021 301 has been a pain, but I am also picky.