Main Motorcycle: 1970 Triumph T100C
Join Date: Aug 2007
Location: Coastal Virginia
Other Motorcycle: 2000 NTB
Grab a beer. This is a long read, and I'll apologise in advance.
Since I've not heard this mentioned as a viable alternative to all of the expensive machining and fabricating, I thought I'd throw this one out there for everyone to chew on. This idea came to me after all this fiddling with each bit to correct an alignment issue more severe than probably most have experienced, changing out swingarms for less bias, and the like. It involves a lot more art, and just as much science, a jig, two torches and a hydraulic press, or a plasma torch and a welding rig.
Most of us are not going to do this on our own, but any decent old-fashioned alignment shop could do it in very short order:
The solution is to bend both legs of the swingarm to the right 1/4" (6.3mm).
I genuinely believe this is the easiest and cheapest way to cure every issue except the brake issue (no good one for that, unfortunately, as the rotor tracks inboard 7/16" (11mm) more on the Honda wheel than it did on the Triumph, and I'm not comfortable putting shims under the rotor, so shims between the caliper mounting plate and caliper will have to do until someone fabricates a 8-11mm thick aluminium spacer that mates precisely to the Honda wheel to push the rotor back to the left to allow for articulation or "float" of the caliper) or we find a better donor caliper that articulates inboard more than the Triumph one does. No kidding--when I torque my caliper down with no shims, it locks the wheel, and holds it fast.
As for achieving perfect alignment, I love precision more than most folks, and spend hours chasing away imperfection, but I also live in the real world. We assume when we purchase a new bike that it is perfect, but we all know it is not. My point? You could take 10 perfectly assembled, brand new bikes and they would all have slightly different alignment measurements. That's why things are adjustable on sensible machines. And for what it's worth, my original swing arm (that will now make a perfect candidate for cutting and bending) was welded "off tack" from the factory by what could only have been a drunkard on Monday morning.
Anyway, just a thought--and Pieman; if you run off with my idea of that custom rotor spacer, I want royalties, mate. Of course, you could always machine a thicker "up and over" caliper mounting bracket, and that would do the trick nicely.
"I'll take a chance, if you'll take the blame."
Ian Stephen McCulloch
Last edited by shoegaze; 04-01-2014 at 12:23 AM.