06 yz 125 wont shift after bottom end rebuild?

I finally got my cases pressed together, both trans shafts spin smoothly. I can also spin the drum by hand and run it through all 6 gears smoothly. The problem is when I  hook up the shift shaft, drum, and shift stopper it won't shift even when I hook up the shifter lever and put pressure on it. If I pry down on the shift stopper to disengage it however I can shift it smoothly by hand again. I did by a new 2007 shift stopper, spring and bolt. Does anyone have any ideas why it wont shift, is the shift stopper installed right? (pics below). Thanks for any help on this.

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Edited by crmaverick

Does the roller on the end of stopper spin? Possibly over peened?

Something incorrectly assembled is causing the shift drum to bind. You need to try and isolate what piece is causing the bind. remove everything until you see just the shift drum, then rotate the drum it should be smooth running through the gear changes. You might have to spin the output shaft to help get through the gears. Then incramentally bolt up another component until you get the bind. You should be able to figure out the problem. Do you have the service manual ?

Something incorrectly assembled is causing the shift drum to bind. You need to try and isolate what piece is causing the bind. remove everything until you see just the shift drum, then rotate the drum it should be smooth running through the gear changes. You might have to spin the output shaft to help get through the gears. Then incramentally bolt up another component until you get the bind. You should be able to figure out the problem. Do you have the service manual ?

 

 

I do have the service manual, I tried spinning the output shaft while shifting. This allowed me to shift with everything hooked up.

 

It wasn't exactly easy to shift but did click in to gears. Is it normal for it to be hard to shift when the motor is off the bike not running?

Does the roller on the end of stopper spin? Possibly over peened?

 

Yup it spins smoothly 

I think I might see ur problem...the mechanism that bolts to shift drum backwards? The piece that sets inside the shift shaft ( little collar) is 180 off. Should it be closer to shift shaft hole, if that makes sense

Its kind of hard tell from pics, but it looks as if the spring tensioned "catches" or pawls are hitting the retaining plate. Maybe the pin on backside is not aligned with hole in piece the pawls holding out

Are you compressing the pawls so that it seats fully into the piece that bolts to drum? I like good challenge every once and a while;)

Are you compressing the pawls so that it seats fully into the piece that bolts to drum? I like good challenge every once and a while;)

 

Heres another picture if it helps. I did have to squeeze the the spring loaded pawls so that they fit into the shift drum. Does this look right? They are flush with the edge when in. 

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Heres a pic with the shift shaft on if it helps. Mabe its normal for it to be hard to shift when off the bike? 

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If you loosen the retaining plate does it make a difference? Are the pawls catching on this plate?

It is a little difficult but with shifter it should be relatively easy...just as before as if you reached down a shifted with your hand. With shaft in, does it budge at all or locked solid?

It is a little difficult but with shifter it should be relatively easy...just as before as if you reached down a shifted with your hand. With shaft in, does it budge at all or locked solid?

 

It does move when pushing on the shifter shaft but doesn't seem as easy to shift as when the motor was in the bike, sometimes it wont shift and I need to spin the trans shaft to get it to shift. When I take just the shifter shaft out I can't push down/up where the shift shaft hooks up to (photo attached pointing with red arrow), is that normal because of the pressure on the drum from the shift stopper? 

 

 

 

 

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Edited by crmaverick

If you loosen the retaining plate does it make a difference? Are the pawls catching on this plate?

 

When disconnecting the shift stopper it makes it easy to shift, loosing the plate didn't effect it. 

Ive never put one together and not been abke to shift with the shifter off the bike...weird. just out of curiosity, how does that stopper compare in shape to old one? Does it feel smooth when u pry it down (feeling just tension of spring)? Does the shift shaft just slide into bore?

Ive never put one together and not been abke to shift with the shifter off the bike...weird. just out of curiosity, how does that stopper compare in shape to old one? Does it feel smooth when u pry it down (feeling just tension of spring)? Does the shift shaft just slide into bore?

 

It feels smooth when I pry down on the shift stopper, the new stopper rotates fine when off the motor and fits perfect into the grooves/bore of the shift drum. Are you usually able to push down by hand where the shifter connects to? Photo attached. It feels locked up when I try to do this by hand. 

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Edited by crmaverick

Pushing at that spot bare handed...probably not.

With shaft installed and shifter attached, you have more leverage

Where in mass are you located? I live just north of haverhill. If you want another set of eyes. Bring your bottom end to my house and i can have a close look at the issue. Im sure we can straighten it out.

Polar is telling you to get your ars over to his house !!! Sorry,I couldn't resist PB. :lol: Seriously, I would take take this man's advice and take him up on his offer,he know's his stuff very well.Fact.

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