Vintage Dirt Bike Q & A

What is the easiest method of getting a cylinder off a '76 250 after you remove the bolts?? Mine seems stuck on there pretty good and I don't want to damage it. Thanks, Mitch

Boy am I impatient. Wooden dowel and hammer. Tap it a few times (more than a tap) and "poof" it is loose. Beautiful workmanship on these old bikes. Too bad someone ran it with a broken piston. Soon, off to the machine shop and back on the dirt.

Check out the condition of rod and big end bearing while you have cyl off.
Also turn the crank, feeling VERY carefully for roughness, Removing flywheel cover will allow you to grasp flywheel and check crankshaft for any movement.
These things can rust up from standing many years.

If the piston broke.......make sure broken bits are not sitting under crankshaft.......otherwise your "new" top end will have the duration of a kids rubber band airplane


Would suggest fitting new crank seals too........on CR, one side easy, other side not.....leaking seals could destroy your new top end.$$$

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'84 Honda CR500
'84 CR125
'85 KX125
'83 IT490
'82 Maico 490
'80 YZ465
'75 Husky CR360 GP Mikkola
'75 CR250
'72 DT2MX
'91 XR200

I'm assuming the flywheel side is the easy side to replace seal?? Any tips on getting the old seal out??

Mitchie,

Keep us posted! I'm ready to take apart a MR motor and will learn from your trials. There is another post here that details some of the parts that cross with the cr (and the ones that don't). ebay is a good source, as well as a few bike graveyards you can find on the web that may have parts.

good luck!

tv

Yes, flywheel side is easy.

Drill a very small hole in seal and thread a self tapping screw...PK screw into seal.
Pull the seal out with pliers on screw.
Two screws on oppsite sides of seal can help if seal too tight.

The clutch side seal needs cases split........
However, you may get lucky and find the trans oil has saved the seal....

If the exhaust blows smoke once engine warmed up.....then you got a duff seal on clutch side......assuming you using correct premix or have correctly set oil pump.

_________________
'84 Honda CR500
'84 CR125
'85 KX125
'83 IT490
'82 Maico 490
'80 YZ465
'75 Husky CR360 GP Mikkola
'75 CR250
'72 DT2MX
'91 XR200

Excellent tips. Thank you