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YZ250 gearbox problem, still here!!! >:(

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So here's the background, I rebuilt a YZ250J for a mate after someone else bodged it up (fitted wrong water pump seals, fitted piston backwards stripped threads, cracked cases.... :p

Anyway, the main problem apart from the piston & resulting broken rings was that when it did run third gear wouldn't engage. First thing I did was check for stripped gears/bent forks etc as it was apart anyway but nothing, next was to install a new shift shaft (original had stripped splines & was bodged together with no way of moving pedal position, pedal was hitting sprocket so I thought probably just not enough pedal travel to put it all the way in gear). So I put the motor back together again & rode it today & it runs nice & strong with no water in the 'box :moon: but still it won't engage third gear :busted: All that happens is it sits & grinds like with a stripped cog or not properly engaged, all other gears work fine. It feels like the drum is going in right & waggling the lever just either procures 4th or 2nd.

Anyone had similar issues with 3rd on their YZ & if so what was the problem? I'm running out of ideas & patience with this bike now so any suggestions would be cool, cheers. Dan.

EDIT-: also if anyone's got a pdf parts book or manual that covers the box I'd appreciate a copy of that to see if the last "mechanic" didn't lose a thrust washer or similar, although I'd doubt that as other gears are good I'd still like to eliminate it.

EDIT 2-:Just found a parts book & there's a possibility that there may be some thrust washers missing if the cluster's been apart, which I don't think it has. Other than that though I'm still stumped... Going to pull engine out again now anyhow, it's gotta be done...

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Cheers for the reply.

Yep, all seemed good. I will be stripping it down soon (not many other options really!) to have a closer look & find out what the hell's going on.

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