1993 YZ 125 Engine Swap

[chronicsmoke]

Hey Guys,

 

I got a project '93 I'm planning on restoring. The engine is all in peices but it's all there except for the cylinder and head.

 

When I was looking at parts I found that the crank is hard to get and when you can find them they are ~700 bucks.

 

Would it be possible for me to take other generation engines and bolt them in? Minor motor mounts aren;t such a big deal, I'm more worried about the carb/swingarm pivot/pipe fitment.

 

Any help is greatly appreciated!

[chronicsmoke]

bump it up, nobody knows how the engines changed at the pivot point on the swingarm??

[chronicsmoke]

Desperate for any info

[MANIAC998]

Sorry, but I'm of no help either. Do you have a buddy with a 125 that you could throw in there to see how it mocks up?

[chronicsmoke]

No unfortunetly I don't.. I'd swap a new generation engine as it's much easier to find OEM parts for (and aftermarkets are a definite plus also) but I want to make sure that the swingarm pivot area are the same where the engine connects to the frame/swinger.

 

If the cases are the same between 93 and 1994-2004 then I'll go to one of those and just fab motor mounts as needed but I'd rather not open a whole can of worms on the swinger pivot/chain alignment and be dealing with custome spacers and bushings.. if It's that much work I'll make a hybrid with a different engine lol.

 

Any thoughts guys??

[Cyclemedic]

I believe 93-95 was the same bike with minor tweaks to motor and suspension. Check with your local Yami dealer and see what they have to say. Also try cross referencing part numbers on OEM parts diagrams. I imagine if the frames are the same, your motors will swap over.

[RyanLester761]

I'm curious if the cylinder from a '96 will swap right on your 93... I know the power valve configuration is superior on the 94+ bikes. I am picking up a 94 yz125 next weekend. I know the 95, 96, 97 all got a bit better as the years went on. I'm curious if I can put newer cylinders on my bike.

 

Regarding the swap: Maybe you can research the swingarm bolt and nut for each year bike. If the bolt is the same part#, then it will probably fit the bike. I think you could shave or add spacers to get the swingarm to fit either engine. I talked to a guy who did a kx500 engine in an aluminum frame crf250 chassis and he said the mod was minimal for the swingarm to fit. Let me know how your progress goes!