Rear Disc Brake Conversion

[RING_DING]

I am putting the cast wheels off a GS750 onto one of my Kettles (the red 1975 M). On the back I am keeping the stock GT swingarm. The problem is that the rear disc caliper torque arm is topside on a GS. I am not sure I want to start welding lugs onto my stock swingarm (trying to keep these custom mods to be "reversible"). Anyway, I searched the Sundial archives and found this picture which shows a rear disc setup with a torque arm bracket that points downwards, and I assume utilizing the stock Kettle torque arm. Does anybody know where I might get such a thing that would work with a GS rear wheel/disc?

[tz375]

Its hard to tell from that picture but it looks like an RD400 caliper bracket. You can machine a bracket fairly simply to take your caliper of choice and use the torque arm in compression rather than in tension or hang the caliper on the low side and take the torque arm straight to the caliper bolts or to an extension on the bracket.

[RING_DING]

Got a mate of mine to move the torque arm bracket from underneath the swingarm and weld it to the top side. Stock torque arm fits perfectly!

[tz375]

Nice looking bike, how are you liking that Strader exhaust now?

[RING_DING]

I'm loving that Strader. It wails like a banshee when it gets going. Would be hard to say if there's any difference in power unless I got it onto a dyno, but it does feel a lot more torquey down low and then there's a bit of a kick once you wind it up over 5000 rpm. What's really nice is that cruising in the mid-range is very smooth, and the surging which was bad before is hardly noticeable. I did take it off recently because I was getting some blowback so I wanted to get a better seal between the headers and the collector. It's not 100% yet, but it might seal when it gets coked up a bit inside. The result of this was that the bracket is attached forward of the stock exhaust mount. I'm actually using the rear footrest mount. This pipe might have been made for the earlier J/K models as I believe there are some differences in the frame dimensions.
One of these days I'll talk my daughter into videoing a drive-by if we can find a suitably quiet piece of road!

[tz375]

What jets/needle settings did you end up using?