Frame Welding: MIG or TIG Weld?

Ok...here's the problem.

Where the top of the side-stand meets the frame it appears that sometime prior to my tender loving ownership she was dropped in some way that caused a weakening of the frame where the sidestand mount (seemingly replaced or rewelded at some stage) meets the underside of the frame.

After an initial reinforcing by a weld this has held well for the last few years but has now given way. After a day at work I came out to the XJ900 to find it leaning on a precarious 45 degree plus angle. A closer look revealed that the side-stand is welded to the frame OK but it's a small piece of the tube frame that has opened up and given way...maybe a prior crash combined with some water/rusting damage.

That's the scenario...now the question: MIG or TIG weld and is it just a matter of using a small piece of reinforcing metal welded against the frame overlapping the good with the bad part of the frame. Bear in mind the problem is not big; I reckon we're talking about 2 to 3 inches in length.

Thanks to anyone that can advise.

Red

 

mig or tig is good, but disconect the battery & pull the TCI.

 

I've seen this problem on a few XJ900s. I have heard of riders claiming that water gets into the frame and sits in that position when the bike is on it's sidestand and rust weakens the frame in that area. Also I think that Yamaha just didn't appreciate the weight of these bikes and the frame tubing just isn't up to the stress and fatigues.
Anyway, I had the same problem on my XJ900, just got the crack welded up with a MIG and then the welder also patched another piece of tubing over the initial weld to further spread the load.

I try to put the bike on it's centrestand whenever I park now....unless the ground is sloped, in which case park it on the sidestand with the sidestand pointing uphill

 

I would tig weld . no splatter and you can control the heat better.

MN

 

Either one will weld fine., just like MN-Maxims said "no splatter with TIG". Since its under the frame it doed not have to be pretty, just strong. You will have to reenforce that section of frame with some tubing to keep it from happening again.

 

Hey...thanks for the replies. And thanks for letting me know this is not an isolated problem.

Not that it's good but it is comforting to find people who have had a similar problem and have found a solution that works.

Since the sidestand has been kaput I've been parking the bike on the centrestand but it's always a little precarious hopping off, balancing the bike and popping it on it's stand while people from work walk by...I keep imagining the embarassment if I over balance and drop it in front of them...d'Oh!!!

Cheers.

 

MN called it. It is easier to get a better weld with TIG. The advantages of MIG are that it's simple and fast when the conditions are known. TIG you can adjust on the fly by dwelling with the torch, feeding more or less filler.