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devincox
08-21-2009, 11:35 AM
I recently wrecked my 07 Kawasaki ZX10, throttle stuck, 130mph, tire wall, helicopter ride, etc. I am now reassembling my bike and noticed the frame is cracked along the welds and in a spot that is perpendicular to the frame. the frame is made from some superlightweight alum alloy and looks similar to these in style at least:
http://www.sumofallparts.net/images/frames.jpg

"The engine is bolted into an all-aluminum twin-spar frame that arches over the engine rather than around it, as with conventional sportbike designs. Constructed of thin-walled castings and pressed aluminum sheets welded together for optimum lightness...." (quote from kawasaki)

I am researching the exact alloy. My question for now is, can this be repaired/welded safely. Some of the guys I race with are saying that I need to anneal the frame after welding or the new welds will be too brittle and just break after the first wheelie.


What are the concerns with welding this type of frame?

I am comparing the costs of welding shop repair, vs new frame (1K+)

Thank you for your help,
Devin

Joezx10r
08-29-2009, 02:33 PM
I know alot of guys who have welded a frame only to have it crack again around the original crack, Something about the heat treating... Some have had luck welding it then welding a plate over top for reinforcing. These frames are notorious for being weak. Good luck!

Switcher
08-29-2009, 04:34 PM
When I used to own atv 4-wheelers, anytime I had a cracked weld I would always re-weld, then add a triangle gusset to make that area of the frame stronger. That way you have at the very least 3 welds (1 side of the triangle not used) origanal weld, plus 2 flats on the gusset.

devincox
08-30-2009, 12:58 AM
I know alot of guys who have welded a frame only to have it crack again around the original crack, Something about the heat treating... Some have had luck welding it then welding a plate over top for reinforcing. These frames are notorious for being weak. Good luck!

Yeah, I have seen some folks say the weld cracked again, because of the heat involved. I was considering using oxy/acet, that way the weld is self annealing.

devincox
08-30-2009, 01:01 AM
When I used to own atv 4-wheelers, anytime I had a cracked weld I would always re-weld, then add a triangle gusset to make that area of the frame stronger. That way you have at the very least 3 welds (1 side of the triangle not used) origanal weld, plus 2 flats on the gusset.

I might try that. first i'm gonna use some stuff I just found online called hts-2000. It's technically brazing and not welding but the bond in the material is supossed to be as stong as a tig weld. I ordered some, so Im gonna find out. I may just weld/braze in a gusset as well.

Thanks,
Devin

MrWild
09-13-2009, 10:21 AM
Have you had the frame checked on a frame table? It sounds bent.

devincox
09-13-2009, 07:33 PM
I haven't yet, but plan on checking it out before atempting any repair.
Devin

cncjunky
09-13-2009, 08:04 PM
Grind the old weld out with a die grinder , and tig or wire weld it. If wire welding you have to get some special wire which I don't have on the tip of my tongue at the moment and from what I remeber when I did it I used a diferent gas too, what it is, I don't remeber at the time. Also from what I got out of trying to do the wire welding aluminum was a dirtier weld. I always go with Tig welding aluminum, but be warned though welding aluminum is much diferent then steels, it takes alot of heat and it welds diferently then steels and stainless. So if you've never welded aluminum you definately need to practice a good amount before you make a mess of your frame. I would'nt mess with soldering or any of that other weld in a tube or whatever they call it it's garbage, thats all it is is clobbed up garbage. If you can't weld it take it to a shop and have them do it for you, you won't regret it. Hope this helps

cncjunky
09-14-2009, 11:47 AM
Also mr wild is probably also right that your frame could be bent, so you should also weld in a support. That still doesn't insure you that it won't crack again, the problem with aluminum is it work hardends.