I have a 87 250R that has been leaking a little oil into my flywheel and have been told that my mains will need to be replaced. Is it possible to do this myself other than the machining or pressing needed ?? I do have a clymer manual for this machine. I am also going to replace the piston and rings at the same time. Does anyone have any suggestions???

PS I am not realy scared of tearing motors down

 

If you heat the cases up sometimes you can get the bearings to fall right in, if not a little tapping will make it go home. Check your seal if your leaking oil as well as your counterbalancer.

 

DaBeech how hard are they to install?? Is there much to worry about loosing??

 

as far as losing what?

 

Dabeechman,

I was checking out your bikes - very impressive. What kind of reed cage is that on your Alky 370?

Thanks

 

esr

 

Is that ESR cage only good for topend/drag racing or is it decent for MX use also?

Thanks for the reply.

 

i would say no, just because they break a lot on me. I dont do the MX thing, but it seems that they wouldnt hold up to the endurance that the MX'ers need

 

I guess what I meant is is this something a amateur could do. I there anything that would fall apart when I split the cases?? Any suggestions would be appreciated

 

Splitting the case is fairly simple. Just take everything down and pry them apart. I recommend you putting the right 1/2 down, and pulling the left 1/2 off so that the tranny will stay put. I put mine up on 2 2x4's with the motor laying down, and pulled the left 1/2 straight off.

The bearings... Well, that's your choice. You can freeze the case and heat the bearing, or you can take it to a place with a press. I recommend pressing them. If you decide to have them pressed, be very careful not to press them too far, but make sure it's in all the way. If not, the cases will never suck up to each other without beating the **** out of the half.

I've replaced my left case 1/2 twice, so if you have any questions shoot me a line. MX26@emailaccount.com Like I said, it's fairly simple.... And my Clymer walked me right through it the 1st time. Go ahead and replace all the bearings when you're down there just to be safe. Also, I run K&S Gaskets and seals. They have held up good for me, but get a new Honda headgasket.