Crack on the case where the bearings sit YIKES!!

[leggers]

OK, so I was reassembling my case and I notice this crack on the inside arm of the top case. If you're familiar with this area you know this sits right above the crankshaft bearing, and is reinforced with a steel bracket.

SO my question is. since this area is reinforced with steel should I be ok to use this top case? or do I need to consider getting a whooooole new flippin case?

Lucas

In this photo you can even see the locating pin is pushed waaay down which is probably what caused the crack...

 

[Olie]

Yep, believe you found the problem. Whoever reassembled the engine last didn't clock the bearing so the pin fit outer race hole. Ended up pushing right through the soft(er) aluminum when they tightened down the case bolts.

But i wouldn't know if it's a deal breaker or not. You'd probably be fine, given that there is a steel insert in the case already and the fact that the bearing has a steel out race which should provide all the support you need. That is, if you're building if for cruising. Tearing around town with doing burnouts might might crack a corner off and send it bouncing around inside. Maybe.

Maybe someone with a bit more experience might chime in.

Note: The first pic is pretty dark but is that crack as big as it looks on the right hand side?

 

[leggers]

Yea it does look that bad, here's another shot from the top down...

 

[gggGary]

Hard telling, there are a lot of "cracks" in the XS650 cases that were there when they were cast 30 years ago and they are still there. I can see what one of mine looks like and maybe a few others have cases open they can look at.

 

[Punkskalar]

yeah, a poor assembly in the past caused that... You can run it, I have torn down STOCK engines that have never been touched internally that were damaged like that... The bearing itself and the others on the crank are very supportive in these engines...

 

[Purplezinger]

This shows how strong these engines really are.

 

[angus67]

ran like that before. if you didnt tear the engine apart, would you have known its there?
go for it.

 

[hooktool]

I have cases. $50 + shipping. PM if I can help. You should not split cases as they are machined together, although if you came across the one half, it would probably be fine.

John

 

[leggers]

ran like that before. if you didnt tear the engine apart, would you have known its there?
go for it.

tru.

Aight. Thats it! Its getting assembled!

Thanks for all the help guys

 

[leggers]

I have cases. $50 + shipping. PM if I can help. You should not split cases as they are machined together, although if you came across the one half, it would probably be fine.

John

If I have issues I will definitely pm you. Thanks!

 

[highspeedhamish]

Just took a picture of mine. These cases were power washed in an automotive shop. I think you might be seeing casting marks... or not.. hard to say.