1985 250R trans problem

[2fiftyR]

Hey guys, I picked up another 250R a little while ago and it has a tranny issue.This thing will shift through the gears,but after it gets to operating temperature,its like you hit neutral when trying to go to the next higher or lower gear.I dont understand why temperature would affect this. It will stay in gear if you hold up or down on the shifter. The shifter will spring back, so I know that spring isnt busted.Is there anything i should check before I tear it down to look at the shift forks and shift drum? This really sucks because it looks like the motor was just gone through. Thank you in advance

[Dirtcrasher]

Take off your clutch cover and check all the external shifting parts, lots of stuff in there wears/snaps/comes loose and it's gotta come off to split the case anyhow.

You may find something simple and easy to fix...........

[ceaserthethird]

Could be they didn't re assemble correctly...

It's tuff when u don't know who did the work :(

[Dirtcrasher]

Your shift return spring is not the same spring that holds the drum in the given gear selected, There is a drum stopper/roller with a large torsion spring on it.

It is also not the springs (2) and hollow pins that engage the drum to shift up or down.

Take the cover off before you think about splitting cases.

If it works fine cold it leads me to believe that something is broke or loose and shows up once it's hot.

And it's definitely not the clutch slipping right??

[2fiftyR]

Thanks for the replies guys,especially dirtcrasher, I will pull my clutch cover and look for anything loose missing or busted. Clutch action is spot on,no slippage that I can tell in this wet,sloppy slushy conditions. I will pay particular attention to the torsion spring on the shift drum, in fact I will order and replace it anyway. Do you think that when it gets to operating temperature that somthing in there expands just enough to create this issue? I cant express how much I dont want to tear down a perfectly good running engine, but it is what it is. Thanks again for your time and consideration.

[Dirtcrasher]

IDK about the temperature thing.......

But, it's not 1 or 2 gears, it's all of them once it's hot which leads me to believe there is some issue with the mechanism that makes it shift and hold in position until told to do otherwise (with your foot) :D

If that spring was broke, the drum would never lock into position. There is usually a shoulder type bolt that holds it in place though. They come loose, the center bolt in the drum can come loose, the roll pin holding the "star wheel" to the drum can shear off etc etc. Once you get the clutch cover off, the clutch out and the plate that goes over the shifting goodies, then you can check things out (only costs you a gasket, just download a free manual here). You may see it as soon as the cover is off or may need to look deeper as stated above and in my other posts.

If you need help, OHIO has allot of guys that know the R well so I'm sure someone could give you a hand if you didn't feel comfortable with it............

[2fiftyR]

Thanks again for the advice dirtcrasher,I am a aircraft mechanic by trade, but I am a little intimidated by this transmission simply because I have never done one before.Where on this site can I find a manual to reference until I can get a hard copy for my garage?

[Dirtcrasher]

MonroeMike and a few other guys usually post the links to the free downloads. Look in "World Class Help" forum at the top of this forum page.

Trust me, even if you have an internal gear issue, being an aircraft mechanic, you won't have a problem with a simple 2 stroke and it's transmission. Very simple, it's right or it's wrong.........

[2fiftyR]

Thank you I will get a manual and tear into it. I will let you know how it turns out. Oh, by the way concerning the its either right or wrong Ive done plenty of the wrong usually because I get in a big damn hurry when I work on my own junk