2 stroke crankcase??

[OldTimer]

I hate to admit it, but I destroyed the left case half on my RM65 trying to press the main bearing.
The question now is whether the cases are match sets?
I noticed that they are sold as sets from factory, but I found a left half on that popular auction web site and now I wonder if it will match up with my right half. I seem to recall reading somewhere that those things are milled and tuned to one another to form a gasketless fit.
I'm gonna try it unless someone knows for sure that I'm in for trouble.

 

[whenfoxforks-ruled]

What the heck happened? I have viewed some on the net who have alleged to have done this,there are a lot of variables in the stories and models.Buying the set would sure suk,BUT,I fortunately yet,have not been stuck with that one!I do know before I bought the set I would look for another motor,unless you can talk your dealer into charging you dealer net price!Hope you have better luck!

 

[OldTimer]

I used the big press in our locomotive shop and tried using juuust enough pressure to move the indicator needle on the press. As soon as the needle moved the bearing pushed through the case. :whoa: OOPS!
Anyhow, I found a matching set of cases on Fbay for 200 bucks, or a left case for 30 bucks. I opted for the $30.00 deal and now I'm trying to anticipate what mistake I may have made this time!
I figure if I use enough, but not too much, Form_a_Gasket, I'll be okay. I could maybe tolerate a very small oil seep, but if it allows the case to suck air, I'm in a heap o trouble.

 

[IndyMX]

Talk about using too much tool for the job...

 

[84cr125]

that sucks. Did you heat the cases?

 

[OldTimer]

that sucks. Did you heat the cases?

I heated the case and froze the bearing and it when in nicely. What I didn't notice was a small lip around the bearing seat that holds the bearing out a fraction. It looked like I had a mm or two left go. So tapped some more, a little harder, a little harder, Is it seated? It looks like it just won't go that last little bit. I'm not going to hit it any harder so I'll just stick it the press and give it a little nudge. If it doesn't move then, I'll be satisfied that it's in far enough.
The rest is history... :bang:

 

[ZOMBIE666]

A locomotive shop ?


i can only imagine how Huge that press must be to be used on train parts :whoa:

i dont think the cases are a matched set but with a little yamabond or liquid gasket you should be golden

 

[whenfoxforks-ruled]

I do not see a leak being a major concern,alignment for the crank and trans would be my main concern!

 

[84cr125]

I heated the case and froze the bearing and it when in nicely. What I didn't notice was a small lip around the bearing seat that holds the bearing out a fraction. It looked like I had a mm or two left go. So tapped some more, a little harder, a little harder, Is it seated? It looks like it just won't go that last little bit. I'm not going to hit it any harder so I'll just stick it the press and give it a little nudge. If it doesn't move then, I'll be satisfied that it's in far enough.
The rest is history... :bang:

sometimes its best not to go with your gut. i did the same thing but i didnt have a press, just a hammer and a socket i didnt think it ws in all the way but it turns out it was, i check by taking out the oil seal instead of hittin harder, lol.