Jump to content

Recommended Posts

   Ok so this is my first post on here so don't hate to much. I have a 91 cr250 that is completely apart aside from the bottom end. When I got this bike it was in rough condition. The only thing I can't figure how to fix ,without splitting the center cases, is the oil drainage plug well. It has a big 1/8" crack in the threads that gets smaller as it goes deeper into the case. Is there anyway I can fix this without welding it say, "JBweld"? And if so can I clean it enough without splitting the case? I already have the clutch side case apart from fixing the kicker. Oh ya whoever had this bike before me tried to seal it with silicon, thanks.

20170411_151442.jpg

20170411_151427.jpg

Share this post


Link to post
Share on other sites

You can weld them that way.  Safest fastest way I can think of is to clean it as well as  you can (I like pinesol) pressure wash etc.   and epoxy it.  Now when you change your oil you end up dumping it out the right side where the clutch cover is.  Decide if that is too much trouble.  If it is go in order depending on how you usually "work"  from taking it apart to just welding it,  drilling it,  doing the best cleanout you can and retap or put your choice of thread inserts in.

Share this post


Link to post
Share on other sites

I haven't seen this issue before...what made it crack? it looks to be still under stress because things don't appear to line up on the left side of the hole in the pic...could try quick fixes...but I, personally, would always worry about it coming apart or worsening unless it were replaced or welded...if you did a quick fix, the first sign you may receive while riding it, if it starts leaking again, is your engine dying a painful death...

Share this post


Link to post
Share on other sites

Ok so really it comes down to time and money. I think I can just weld it but idk if I need high frequency tig or if I can just kinda spot weld it with mig enough to build it up around the outside and bottom. 

  • Like 1

Share this post


Link to post
Share on other sites
31 minutes ago, Tony Barone said:

Ok so really it comes down to time and money. I think I can just weld it but idk if I need high frequency tig or if I can just kinda spot weld it with mig enough to build it up around the outside and bottom. 

I have done it over the years.  Some people get really wadded up about things like that.  My take is that if you open it up,  you will be facing about 5 bills to put that bike back like it could go for several seasons.  Or you just take it apart and stick a case on it and throw all the other mains, shift forks etc back in the way they came out,  because someone's imagination is running is running away with an oil spill the size of Valdez,  and an old transmission going with oil for a few minutes.  Worst case and likely in the catastrophic since.  If you don't mind looking really shade tree changing your oil,  welding it in, jbing it in and dumping out of the clutch side works fine.  If you want to weld it in and retap,  that will work too.  Small amounts of ash and small amounts of aluminum left on the drill and retap are going to be pretty much next to harmless with just small amount of care. 

Share this post


Link to post
Share on other sites

I have a millermatic 185  wire welder with a spoolmate 185 and ER4043 .035" wire. Should I use 25 75% for my gas? And can I use this wire for it?

20170611_190935.jpg

And any suggestions on how to set it?

Share this post


Link to post
Share on other sites

I would find a broken case and play with that for awhile before trying it on the one I was going to keep.   My friend has the same unit and things you are starting too cold.   Just find a case and play for a minute.  

Share this post


Link to post
Share on other sites

Welding aluminum like that will be a nightmare.  The parts have to be 100% clean, which will be nearly impossible to do with a part like that.  Any oil or contamination is going to compromise the weld.

Share this post


Link to post
Share on other sites

I cleaned it up better but I don't have a picture of it. I'll take one when i get the case back from my mechanic. The welding went pretty well I couldnt get more than a 2 inch weld at time on it, but I ground it down and kept building it up. It was a lot easier than I thought it was going to be, thanks to the guys on the miller.com forum and your help too.

Snapchat-2087288433.jpg

Share this post


Link to post
Share on other sites

The problem I'm having now is one of my Showa fork tubes is longer than the other by 1 centimeter. Is there any way around not tearing them completely apart or can I just take up the difference when I mount them?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:


×