I just bought a 92 250x in emmaculate shape for a pretty cheap price. The only thing is that the guy I bought it from failed to tell me that the casing was crack(a hairline crack)on the left side. The chain apparently came off and cracked it. I was wondering is there anything I can do to patch this up rather than buying a new casing cover?

 

Silicone it,I had a 750 Yamaha Seca motorcycle and it had a button size hole in the side of the crank case and I put silcone over the hole and could not believe it held up under all the heat.I was going to fix it but I just told the guy who bought it to just keep a eye on it.

 

You can remove the casing cover and have it welded back. While the silicon may work for a while, it will not prevent the crack from probagating under all the vibration these machines are exposed to. If you decide not to have it welded, you may want to drill a small hole at each end of the crack to help prevent further crack probagation prior to using a patching material. Also, instead of silicon, there are a number of patching materials available at most auto parts stores especially made for repairing metal.

 

take the case off and coat each side with a liberal amount of JB weld.

It should hold it.

 

Personally i'd just take it out and have a welder weld it back together. Either that, or keep an eye out on ebay i've seen a few people selling them over the last few months.
mike

 

theres no need to get it welded. my counterbalncer broke off and put a hole in my case. my dad and i fixed it with a peice of metal and some JB weld. for just a little crack you could put JB weld on it and it will be fine.

 

Thanks all but I decided to use JB Weld and it did it. Sealed up the crack without any leaks. Again thanks!!!

 

keep your eye open for those sidecases youll prolly whack it again i have like 15 junk ones lying around i snag up everyone i can find i JB weld them till theres nothing left to them but thats only a temporary fix if you ride hard youll hit them. right now im making a case saver that should save it for a while if your running stock gearing i suggest you get one!

 

thanks MX265X I think I am going to check that out for both my 250x and 300ex. Better to be safe than sorry!