I have a wrecked 2008 600rr that i'm trying to repair. The one thing that is concerning me with this bike is the fact that the case is cracked. The bike went down hard on the right side. It landed on the frame slider which in turn broke the tab which the frame slider screws into on the motor. When the tab broke off, it breached the engine case.

I know its possible to weld cases. But what concerns me is that the crack is in the case just below the head. If I get this piece welded back on, is it going to be strong enough to hold? Also, will I have to weld this piece back into place, as well as weld it to the head (which sits right on top of this piece)?

I really hope I'm not completely screwed here....

 

Pictures would help out a lot, it would do a lot better than just an explanation.

 

Yea i'm sorry for the confusing explanation, I'll try and post a picture along with this reply.

A little further information on the location of this crack:
The piece that broke off (as you will be able to see in the picture) is on the right-most (sitting on the bike) side of the engine. It looks like it is on the part of the engine perhaps where the cam chain runs vertically to the cams? My initial concern was that this crack was actually in the wall of the cylinder, exposing the combustion chamber. This is not the case however, so I think welding this should be a good possibility. Any further advice/input/reassurance would be much appreciated.

The picture shown is of a 600rr with the tab STILL INTACT. The tab- shown here in dark gray just to the right of the silver spacer- broke clean off the case, which left a 1/2-square-inch hole in the case. The piece fits right back into place nice and snug/clean. I'm guessing that when I get it welded back on, I should NOT weld it to the head (which sits right atop this broken peice), correct? The only reason I ask is would I need the extra strength of welding it to the head to keep it in place?

Also, what preperation steps should I take in assuring this gets done correctly?

 

A picture of your broken piece would help a little. It would help to see just how bad it is.

As far as welding, it can be stronger than the original in some cases. From the sounds of it, you really shouldnt have much issues with welding it. Other than you may have to replace gaskets since the heat produced by the welder will be much higher than what the gaskets would be rated for. the other issue is going to be keeping the proper location. The welding will cause the mount to move around a lot. The best bet would probably be to have the mount bolted in place by the frame, or some sort of jig to hold it while its being welded.

As far as what steps you have to take. Only one. Take it to a licensed welder. They will do all the steps needed to weld it back up. In a case like this, especially with aluminum, you don't want to take it to your uncles friend who knows a guy that welded aluminum once. Pay the money to get it done correctly.

Oh, and don't weld the head to the block. But, if you take it to a reputable welder, they wouldn't do it anyway. The only real problem I see is how close the head is to the mount. On thicker aluminum like this, the bead will be fairly wide. The welder will probably have to put a small weld on top and around the mount, and then gusset the bottom of the mount with piece of aluminum.

As far as cost, I would assume around 50 bucks to have someone weld it. It may take a few calls to find someone that will weld it with the engine complete. Some may want the engine disassembled before they weld it, or they may not guarantee the weld. Contamination of the weld is much higher with it together.

If you do find someone to weld it while its still in the bike, ( would be the best bet for alignment), make sure to remove your gas tank, (obvious), but also disconnect your battery. the electrical charge from the welder can fry your ecm. but again, any licensed welder will know all of this already.

Sounds like its time to start making some calls to some welders with aluminum experience.

 

My fear is that if the broken piece is as close to the head as you say that you may need to take the head off before you weld it. Just welding it from the outside of the case may not be sufficient.
Can you post a picture of the actual hole/damage and it's location.
Hope you didn't get hurt in the accident! No flesh welding required.

 

aluminum can be tricky to weld, but a good welder should take steps to keep the heat localized. will it hold-yes .will it break again if wrecked -yes. IMO you have nothing to loose but to try. youll know if the repair is worthy. a crack into a wet part of the engine woul be a way bigger problem, as oil will try and contaminate the weld process. note: aluminum welding is very dependant of the material being sterile clean for a good weld. I would say clean area very well , and weld it back on. ive done this a couple of times for different folks, its very doable and nothing has come back broken again.

 

Thanks for the reassurance fellas, all the help is much appreciated. This forum is outstanding.

Also, in response to HenryM's statement about the accident - i am grateful that it wasn't me who wrecked this bike. I bought it as is and am rebuilding it. My regards go out to whoever it was behind the handlebars of this thing when it hit whatever it hit- from the looks of the bike, it wasn't a pretty impact!

 

Yes I'm sorry, as I looked at the first part of your story again I realised that you sadi you had bought it as a wreck, not caused it to be one. Phew! Poor bugger that was behind the bars though. Makes you think twice doesn't it?
Good luck with your repair.

 

+1, pics will tell the story