Welding 600rr frame.

So, I had an off this past weekend, and one of the tabs where the rearsets bolt to the frame snapped off. I brought it to a welder who does a lot of aluminum, but motorcycle frames are definitely not his forte.
Does anyone know what type of filler rod would be best? And any other precautions I should pass on to the welder. Thanks in advance.


Pic of the break

 

Being that it's cast, it's going to be wierd. I have welded on my old cbr frame before, but with lots of work. Clean the area around the weld about an inch back. I removed what was left of my rearset mounting point. (Broke like yours). Took a solid piece of round stock and beveled the edge. Preheated the cast just a little to get some heat in it. Once I was ready, I used 6061 filler rod and put in several good beads. I ground the first weld nicely and made room for more weld. After was all said and done, iirc, I used a 7075 filler rod to cover pass it all. Once. Cooled I drilled and tapped the round stock and never had a single issue. But in reality I think the 4043 high silicone content would have been better.


97

 

5356, build it up..grind it down...drill n tap...done.

 

Thanks guys.

What's your opinion on welding it up as is, with the swing arm on there. Will the heat transfer enough to damage the bearings in there?

 

No it won't hurt it, IF you don't let the heat get out of hand...(unless the guy is using an antique welder and is a hack)..you can cool it off with a wet hand towel..it isn't Rocket Surgery , just use Common Sense.

 

If that bottom one is cracked, break it off grind back what is left of the threads using a carbide burr and weld it up too...

 

The bottom tab shows no signs of stress at all, which is weird considering how it went down, but who knows. I guess I'll wait till the next time..

Thanks again Britt. I was hoping you'd chime in.

 

Make sure you unhook the battery and unplug the ecu.

 

And OR, Hook the Ground to a Clean Shiny spot on the FRAME. (If you're welding on the frame, hook the ground to the frame, if you're welding on the swingarm hook the ground to the swingarm...not the frame..it will run the power thru the bearings.

The TIG welder High Frequency hunts for Ground...if it isn't direct it will go thru the shortest route...maybe the gauge cluster...ecu..whatever is handy, once it establishes the path, it arcs out.. I have welded on tons of bikes and never removed or disconnected anything, but I am careful about where the ground goes.

 

Will do. I have to swap out the throttle cables so I'm gonna send it over with the tank off too. I'll disconnect every sensitive device and disconnect the harness grounds while I'm at it..

 

I was going to put a long shank bolt in the lower mounting point and a lock nut so the shank will be exposed and the bolt tight. Figured that would suffice as a good ground point, since the frames all painted, and that is close to the spot to be welded.. Though, I'm not sure if ground point distance matters..

 

Closer is more good'r..always..like a condom.

 

What about 4043? I always thought that was better for castings. It flows really nice and clean.

 

It is all preferential, I like the 5356 for this application because it taps and holds better.. the casting is not like old Harley Cases or some shit sand casting.. they are Investment Cast.. it is much like A356.. when welding, and machining. (In this case as welded, drilled and tapped)

Please note all of my suggestions are that.. and not always textbook, and are more from the last 42yrs of welding on all different kinds of things... it should all be taken with A Grain of Salt and A Pound of BullShit or The WeldingGospel.. it is up to the reader to decide..

 

Me too but after having a guy that worked for me burn up a computer in a van because he forgot to unhook the battery I'm paranoid.

 

I struggled for years with the "Hows it work"...is it better to have a complete circuit or an open circuit?? If welding on a vehicle, and the ground is correct, it makes little difference, however, if the ground is not right..it will hunt to complete the circuit..sometimes like on an older GSXR subframe that is Clear Anodized..you hook to that and are welding on the frame or even the sub-frame..it may NOT actually be grounded..as Clear Anodize is non conductive..so it will hunt the short circuit...and wherever it is gets zapped, fried, powered up, and you may not even know it if it is internal as in the ECU, GaugePod, and even some other electrical parts, like the PowerCommander..AutoShifter..all that extra expensive stuff.

When I was 16, I had a job welding for a shop in Panama City, guy brings in an early Winnebago..wanted a channel iron motorcycle carrier fabbed up and welded to the front of the frame..we disconnected the battery, I hooked the ground lead to the frame..clamped the channel to the frame and proceeded to weld that shit on..it somehow didn't ground thru the paint and clamp..instead it ran tru the alternator and killed it...I lost my weeks pay..@$2.65hr in 1977 it was a tough lesson to learn.
The Ground lug may may have been touching the metal on the battery tray, when I tried to strike the arc it shorted out and short path was thru the alternator...all I can figure, and it has been on my mind for over 40yrs.

 

That makes sense, thanks. It will be relatively soft without any post treatment, would you already helicoil it just to be safe or never seen a need?

This is true for all things, whether textbooks or teachers.

 

Never really saw any need for thread inserts in a proper repair.. unless it is on a part that is removed frequently.

 

That's always been my thought process on the matter. FWIW I've had PCM's go south just from unhooking the battery to do other work on a vehicle. We try to not disturb anything we don't have to on vehicle now a days. If I can get away with not unhooking a battery to replace a starter or alternator, i'll do it.

 

Should have told that dude to eat a dick and walk off. If you did some seriously stupid stuff I could see him collecting money from you but an honest mistake like that? I obviously don't know the details but isn't it possible it was just a coincidence?