Problem shifting into 4th

[DConwheels]

I am having a problem with shifting into 4th gear on my cr125. When I go to shift it acts as if it is in neutral. If I try hard it will go up into gear. I wonder if it is possible I am missing 4th gear totally. Has anyone had any experience with this type of problem? I am prety new at working on the bike but seem to be able to do most things. Any help would be appreciated.

 

[76GMC1500]

The shift fork is probably worn or bent.

 

[dezryder]

I second the worn/bent shifting fork.

 

[DConwheels]

How easy is it to get to and replace the shift fork?
Do I need to take the entire engine out of the bike?
The manual talks about some special tools needed (crankcase splitter?) is that needed?
I did the top end work with no problem but this worries me a little. Any help would be nice.

 

[Ol'89r]

How easy is it to get to and replace the shift fork?
Do I need to take the entire engine out of the bike?
The manual talks about some special tools needed (crankcase splitter?) is that needed?
QUOTE]

You will need to remove the engine and split the cases. You can leave the gears in the right side case and just remove the left side case to access the shift forks. You will need special tools like a flywheel puller and case splitter to do it right. It is easy to make a case splitter or adapt a steering wheel puller to do the job.

Also, check the gears for worn dogs where the gears engage. If the dogs are worn it will damage the new shift forks fairly quickly.