Gettin' ready to split cases on '91 KX125

[mobrown]

Okay so I got the primary gear, stator, clutch and kickstarter gear off and the motor is on the table and I'm ready to split the cases (crank needs replaced). I'm wondering if anyone out there has worked on a KX this old and can offer any "make sure you do this, or don't do that" advice. By the way this will be my first motor teardown.

I noticed in the manual there's some tool used to create a barrier between the cases and the crank during installation and was wondering if that thing is absolutley necessary. I've read numerous threads about installing bearings (heat cases and cool bearings) and have a good sense of what to do and I am asking others what sucess and/or problems can I look to occur or try to prevent.

I gretaly appreciate any and all input/advice

Michael

 

[MXRose3]

I do it the poor-mans way...lol
You'll need a puller to split the cases (I've used steering wheel pullers from Pep Boys before - the kind that look like a peace sign). Make sure you lay the engine on the clutch side when you do, so none of the tranny parts fall out. When you put the new crank in, I have had some luck with heating the cases and freezing the crank to ease installation, but I believe the tool that you are referring to is a tool that is used to pull the crankshaft into the left case-half. I have used everything from a couple of old (larger) main bearings with some stacked large washers or box end wrenches with good luck. Just crank down on the magneto nut to pull the crank into the case. You may have to tap on the swingarm bolt mount a little to make sure it is going together evenly and the tranny is lining up. You can check this by occasionally spinning the countershaft sprocket shaft.

 

[mobrown]

I do it the poor-mans way...lol
You'll need a puller to split the cases (I've used steering wheel pullers from Pep Boys before - the kind that look like a peace sign). Make sure you lay the engine on the clutch side when you do, so none of the tranny parts fall out. When you put the new crank in, I have had some luck with heating the cases and freezing the crank to ease installation, but I believe the tool that you are referring to is a tool that is used to pull the crankshaft into the left case-half. I have used everything from a couple of old (larger) main bearings with some stacked large washers or box end wrenches with good luck. Just crank down on the magneto nut to pull the crank into the case. You may have to tap on the swingarm bolt mount a little to make sure it is going together evenly and the tranny is lining up. You can check this by occasionally spinning the countershaft sprocket shaft.

Thanks MXRose. I just read the manual and the tool is a jig used to ensure the crank goes in square when using a press. However since I am not usign a press (hopefully the heat/cold and the magento nut will work) I suppose its's a moot point.

I'm wondering if I should change all seals ad bearings while it's apart and if I do how much is involved (or how much trouble) in installing tranny bearings.

Thanks again.