Swing arm brace - chain rubbing

[bosco659]

On my recently acquired ‘76 XS650C, the p.o. installed a swing arm brace - it may be a Joe Wiseguy swing arm / brace. I noticed that if there is any slack in the chain, the chain will rub on the top of the brace. Worried long term about damage to the swing arm and chain. Had anyone had this problem and what did you do to protect the swing arm? The p.o. stuck a piece of pvc pipe on the arm where the chain would rub. The chain had already worn grooves in the pvc so this isn’t a good long term solution. I’ll try to post pics tomorrow. Thx

 

[Hamos]

Same here mate. Not enough clearance for the chain on the swing arm brace. Chain has to be on minimum slack.
Not sure of the fix. I may likely get a notch cut out and re-welded. A bit of work and will need re painting, but not really enough room to adequately strap a guide of some sort.

Would be good to hear of any solutions.

 

[Jan_P]

Stock ??
Correct tensioner ? not flipped around
Wheel sitting in the middle ...? Lining up with center line of the bike ?
Measured from swing to tire edge ? at front of tire equal distance

 

[Hamos]

Stock swingarm with a welded on brace underneath.
Similar to this thread:
http://www.xs650.com/threads/swingarm-brace-vs-crossover-tube.48249/

All alignment is perfect, rear has longer shocks so that may be contributing

The lower chain run rubs against the brace if there is anything more than minimum chain slack. I need to either add some protection to the brace, alter the brace, or add a tensioner wheel up towards the front sprocket to lift the lower chain run to gain clearance.

 

[Jan_P]

Depending on bike look
And how severe it is .
I would probably investigate look into other shocks ..perhaps after trying to test with these existing pulled in a bit.
Welding and painting is some work
A tensioner might not work well with a bike with rear springs ( don't know though ) And again installation problems welding perhaps

 

[bosco659]

Stock swingarm with a welded on brace underneath.
Similar to this thread:
http://www.xs650.com/threads/swingarm-brace-vs-crossover-tube.48249/

All alignment is perfect, rear has longer shocks so that may be contributing

The lower chain run rubs against the brace if there is anything more than minimum chain slack. I need to either add some protection to the brace, alter the brace, or add a tensioner wheel up towards the front sprocket to lift the lower chain run to gain clearance.

The po stuck on a split piece of PVC pipe on the swing arm to protect it from the chain. I like the idea of a tension wheel. I’ll try to get a picture of the pipe “guard” and post it later this week.

 

[willis]

Maybe add a piece of delrin on top of the swingarm? Think dirt bike.... They all have guards for this same reason. Maybe one could be modified and utilize the chain guard mount point?

 

[5twins]

Chain rub seems to be an issue with many of those weld-on braces. Simplest, cheapest solution I've found for a better, stiffer swingarm is to swap in one from the old TX750 twin. It's a virtual drop-in replacement having all the same dimensions as the 650 one except for nearly 1/4" larger arm tubes .....

The TX750 had oiling issues and many trashed their motors well before the 10K mile mark. This is a good thing when it comes to sourcing chassis parts because many are quite pristine with very little use on them. Both of the ones I got were in such good shape that the original plastic bushings weren't even worn and I'm still running them.

 

[willis]

The TX swingarms have gotten hard to come by it seems. Been watching Ebay for a few years and not seen any come up.

 

[ThatXS650Guy]

I was looking at one of those swing arms braces but then I was told that you can't use them with a center stand. That was a deal breaker.

 

[GLJ]

The TX swingarms have gotten hard to come by it seems. Been watching Ebay for a few years and not seen any come up.

https://www.ebay.com/itm/1973-Yamah...191422?hash=item56f5b0c9fe:g:pQEAAOSwoyFgRl1B

 

[gggGary]

Like the look of the braces.
But snag Radian arms to stick in my projects.

They come with top guards, and need them especially with small rear sprockets.

 

[bosco659]

Like the look of the braces.
But snag Radian arms to stick in my projects.
View attachment 186668
They come with top guards, and need them especially with small rear sprockets.

Is the Radian swing arm a straight swap or mods needed? Is it aluminum or steel?

 

[gggGary]

Is the Radian swing arm a straight swap or mods needed? Is it aluminum or steel?

Radian axle is 17mm not 20mm shock mounts are spread out a bit, it's longer. Since the arm is taller, there's a bit of a chain rub issue. That's about it. Radian is drum so it's got the torque mount on the bottom.
Ywain (shown) is using a GS500 rear wheel.

 

[bosco659]

K thx. Maybe a next winter project.