Gear Box Broken?

[Wild Hare]

(Friends kid's bike )
Gear Box Broken?

The bike is a '96 CR-125. Bike started and was placed in first gear, bike died presumably just be cause it was cold still. Went to shift back to neutral before restarting...bike will not shift. The bike will kick through with the clutch pulled. Clutch feels okay and the bike kicks through okay. I'm thinking GEAR BOX. Is there any way to check it out without splitting the cases? (You have to split cases to get at the gear box, right?) I'm I missing something else I should check? Any "return springs" or something easy I could check?

Any recommendation's on a west coast ( LA area ) engine shop that could fix it? I don't trust the local dealer INSIDE the engine...

 

[HLT]

With the bike on a stand, take the spark plug out and turn the rear wheel slowly. If there is a gearbox problem you should be able to hear and feel any clunks or bad noises without doing any damage. This may also help you get it out of gear. From what you say, it sounds like the kid may have a bent shift shaft. If that's the case, the cases don't need to be split.

 

[David Trustrum]

Do you mean the lever isn’t moving or returning or it’s just not getting into gear?

Drain the oil & water & pull the RHS side cover. Beneath the clutch & to the back you will be able to see the shift lever shaft acting upon the outside of the shift drum (the rest of which that lives in the cases & plays with the expensive bits).

It may be the gear shaft cannot rotate this due to say one tag broken off. Tell us if you see anything broken or bent including the spring.

You often have to rotate the wheel or engine a bit to shift it with engine off.

 

[Wild Hare]

Went over to my friends last night to help with the diagnosis....

Well it's bad, pulled the chain and small sprocket and the case is BROKEN. The case is broken all around the seal for the counter shaft, ball bearings fell out with the oil seal. I suspect that one or more of the ball bearings is rolling around in the gear box. I felt really bad for them, but I saw the kid running a chain that was so shot I could see several kinked links weeks before this happened...I explained that the chain could break and take out a case or cause other problems...the chain didn't break but I suspect the loads from it caused the bearing to fail, then it ate it's self.... :eek:

So what did we learn here kids? $40 worth of chain could have saved $700 worth of repairs. ..dealer estimated it yesterday, and it could go up if gears are broken! :(

I feel sick, but I told them...somehow that doesn't make me feel any better! :think

Any words of wisdom about spliting cases and repairing gearboxes?

 

[David Trustrum]

Ouch!