Reality check - Radian swingarm conversion from experience

tintin · Full Member Joined: May 07, 2007 Posts: 96

So, like many, I read the many posts etc. eschewing the benefits of the Radian swingarm, and how it was for the most part a simple bolt-on mod.

Sure, people went on about the 17mm axle needing different bearings or a sleeve to work with the XS650 wheels, but that seemed to be it.

Here's what I've experienced so far in my quest.

I have a 1972 frame. Bought a Radian swingarm for a deal ($50 + shipping) on eBay. Came with all the bits and pieces, including axle, swingarm bolt, brake stay, needle bearings/dust caps in place etc.

Threw it on, and sure enough, the pivot bolts right into the 1972 frame.

Then I mounted my old shocks - the left one isn't bad, but bottom line is the shock mounts on the Radian arm DO NOT line up with the frame at all. A good 1/2" or more wider on the arm than the frame.

So, definitely the shock mounts need to be brought in-board on the swingarm. Then when deciding where to mount the shock mounts, we realized the Radian shock mounts and arm in general is 3 INCHES longer than the stock XS650 arm.

Am I nuts or is this more info than has been posted in the past? Am I working with some weird combo of 1972 frame and Radian arm?

I'm having the shock mounts put 1.5 inches further back than the stock XS650 arm, splitting the 3 inch difference. They're being mounted on top of the Radian arm to line up properly with the frame. I'm also having the chainguard mounts removed and the little threaded hole on the left side filled in and smoothed over. It will be powdered black with the rest of the frame and bits.

I'm also having the Minton Mods bracing done to the stock swingarm and will use it instead. I'll keep the modified Radian for another day or will sell it as a much closer to reality bolt-on mod.

Did I miss all the posts from the many people who have apparantly done this themselves? Where is all the info on this mod?

INXS650 · 650Rider Supporter Joined: Mar 22, 2007 Posts: 645

Thought about that myself, then decided would just get a radian if I wanted the swingarm. Too much agravation for me. Unless you plan on drag racing, alittle bracing is all you should need.

mikenfl

TX750 swingarm is about 1/4" larger in diameter than an XS650 and fits without all that BS. Wink

5twins · Full Member Joined: Aug 05, 2006 Posts: 1616

Amen, I never should have spilled the beans. When I mentioned it about a year ago, I was really surprised no one knew (well I'm sure someone did, they just weren't tellin'). For as long as these bikes have been around, I thought all the secrets were out.

What a difference that arm made. The back end is so much better - and I replaced a stocker with new bronze bushings - with a plastic bushed (unworn) 750 one....

tintin · Full Member Joined: May 07, 2007 Posts: 96

Well I ended up having the shock mounts moved on the Radian, as it was relatively cheap while I was having the frame braced anyhow. So now I have a truly bolt-on Radian swingarm that I can sell if I decide to not use it.

The chainguard tabs are gone too, as well as the little threaded hole to bolt that rubber protector on - it's smooooth.

When I go to the powdercoaters I'm having both the stock and Radian arm done up. I'll probably just run the stock arm with bronze bushings for now. Didn't end up having it braced - was going to be a fortune. Might have it done in the future if I can get a better deal, but people have said most of the flexing occurs up at the frame anyhow, and it's braced out the wazoo now.

I much prefer the vintage look of the stock round arm, and am building a Triton look-alike. If old Norton featherbeds could do with round unbraced swingarms, I'm sure I'll be fine on mine Smile

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