Re-threading axle for Radian swingarm

[bkaushansky]

Please validate my logic.

I'm using a Radian swing arm with a CB750 axle (20mm). Rather than turning the axle further down at 18mm and adding threading to accommodate the shorter required axle length, I was thinking about trimming the axle and re-threading for 20mm. Other than getting a new castle nut, it seems to be the easier solution.

Thanks for any input.
B.

 

[crashcourse]

Can't see any reason that wouldn't work, if all the other dimensions match up.

 

[jetmechmarty]

Why not just use a couple of spacers on the outside? As I recall, that axle is not too long by much.

 

[racerdave]

Jetmech is correct. I just looked at mine. I had the Radian axle blocks drilled out. Used the castle nut and a 1 inch long spacer that came with the CB axle left at original length, and used the original cotter pin hole. If you could have custom spacers cut to about 1/2 inch long each, use one on each side, you could use a rear swingarm stand there then.

 

[crashcourse]

One thing to be careful of: rule of thumb for threads is you want at least a diameter's worth of threads. (If you have a 1/2 bolt, you need at least 1/2 inch of thread). This guarantees adequate strength. If you can't cut off the old threads and get enough length of new thread, it would be better to turn down the bolt and extend the old threads. Finally, having a different diameter bolt will change the torque spec for the axle nut. I would use the spec from the 750.

 

[bkaushansky]

You brought up a good point.... If I use 1/2" spacer on either side, I can use a race stand on the swingarm hooked to the spacers. I don't have the center stand anymore, so this is a good option.

Thanks.