Replacing a 90 degree bend in a motorcycle swing arm

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Hi there,Just wondering how to go about properly sleeving and fitting a 90 degree bend into a swingarm without bending it apart.....This is what I've envisioned so far...would either of these be sound enough?  It's 1.75" DOM tubing, swingarm of a honda shadow 600 I'm trying to mount a fender to the swingarm, bobber style....thanks! Attached Images
Reply:or this....cut slits in both sides of the joint, insert sleeve in one side with hole drilled and stiff wire through it, position bend and then pull sleeve into middle and weld....thoughts? Attached Images
Reply:The largest pic, with the mitered cut is a better bet. Let's start with the usual; I hope to hell you know what you are doing as  a weldor, and I will assume you do for simplicity's sake.I'd bevel the pieces, and get a weld on the sleeve to the 1st. piece. Then, butt the other piece in, and run a full pass to tie it all together. I am trying to envision where in a Honda Shadow there was a 90degree bend in the swingarm; and if there were, what form of gusseting surrounded the area? The only place I could imagine is right up near the pivot point. And, that id a very poor place to be cutting and rebuilding a swingarm without some knowledge of necessary gusseting for support.Were it me, I would rather weld a couple tabs onto the tube, and not cut it. Better you save the cut& fit work for the fender itself. For reference, I have ridden many thousands of miles on swingarms that were modified repeatedly on road race bikes from 250cc to 1100cc. And every swingarm cut and welded came out with 2 times the gusseting that it started with, without exception. They have to be set up in a jig, and after welding, be checked for trueness, lest your bike ride off camber, and the swingarm is rendered useless. I HAVE climbed onto a racebike that this happened to; let's just say that it makes me consider this a very possibly 1 way trip to the scrap pile for the swingarm, if not the whole bike.And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:here's the issue....see how the right side is too close to the fender? Attached Images
Reply:I see it; how does the bike ride right now; alignment of rear wheel?? Can you post a side pic, maybe a bit downhill, like a 30 or 45 degree shot. I'd like to see the junction of that bend, before I would say anything on how to best proceed. Also, there are several very good chassis guys around here who will also be able to give you a good idea or 3 with a couple more pics to sort through. Thanks!!!And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:here ya go...its right beside the upright that the monoshock bolts to so it would have to be plenty solid Attached ImagesLast edited by shepdog; 11-27-2010 at 03:26 PM.Reason: add
Reply:If it were mine, I would do some careful cutting and replace that whole top hoop rather than piecing it in.My name's not Jim....
Reply:Damn.  would be a lot easier and give me a chance to adjust the ride height too....nice one.might i ask some of the pros on here what a job like that (replacing entire top loop) might run one?
Reply:To make a matching replacement might be difficult. Here's another idea:1. Find another swing arm to be a donor.2. Cut the left side off.3. Replace the current right side with the donor left side.This way you know you'll have the correct radius and tubing. Just be careful to not damage the existing lugs when you cut it a part.Ian TannerKawasaki KX450 and many other fine tools