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Discussion Starter #1
I'm sort of new here, been lurking for almost a year now. I'm currently in the process of building up a 1976 CJ360T which came to me as a frame with engine and not much else.

I am currently trying to get the trashed wheels replaced with cb650 wheels that I got a good deal on. The only problem I ran into is that the rear wheel's axle bolt is a little too wide to fit through the cj360t's swing arm. I am new to building bikes so forgive any naiveness or ignorance that the following questions may contain:

1. Could I just gently use an angle grinder to make my current swing arm's "holes" wide enough so the axle bolt fits?

2. Would a cb650 (or any other larger bike) swing arm mount to my cj360t's frame with little to no modification? I tried to find dimensions or examples of people doing this but failed.

3. Does anyone know the dimensions for a cb650/750/etc swing arm? (in case no one knows if it will fit)

Thanks!
 

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1) I seldom set a frame or swing arm up in my mill to modify it to accept a larger axle unless it has to be setup for something else much more critical anyhow. I do just exactly what you describe. Do your layout work carefully and pay attention. Last one I did I used a thin whiz wheel on my air angle grinder. Both slots were held to within 10 thou and I didn't check before but I doubt it was any closer to begin with.....

2) You are asking yet you have both the patient and organ donor bike on hand?

3) Do you not have the donor bike yet?

Unless you see something superior about the 650 swingarm (and my guess is it will likely add inches you don't need to the wheel base) just open the slot up
 

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1) I seldom set a frame or swing arm up in my mill to modify it to accept a larger axle unless it has to be setup for something else much more critical anyhow. I do just exactly what you describe. Do your layout work carefully and pay attention. Last one I did I used a thin whiz wheel on my air angle grinder. Both slots were held to within 10 thou and I didn't check before but I doubt it was any closer to begin with.....

2) You are asking yet you have both the patient and organ donor bike on hand?

3) Do you not have the donor bike yet?

Unless you see something superior about the 650 swingarm (and my guess is it will likely add inches you don't need to the wheel base) just open the slot up
 

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Discussion Starter #4
Thanks HackAsaw. I didn't think my modification idea was too far off, it just needs to be opened up a few millimeters so I didn't think it would effect the structural integrity (wanted to check with you guys though).

I don't have a donor bike, or a swing arm available which was why I was asking :) I liked the idea of just bolting on another swing arm and being done with it. I didn't think about the added length, which is something I know I don't want.

Thanks again!
 

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Discussion Starter #5
Thanks HackAsaw. I didn't think my modification idea was too far off, it just needs to be opened up a few millimeters so I didn't think it would effect the structural integrity (wanted to check with you guys though).

I don't have a donor bike, or a swing arm available which was why I was asking :) I liked the idea of just bolting on another swing arm and being done with it. I didn't think about the added length, which is something I know I don't want.

Thanks again!
 

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The other solution is to change the 650 wheel bearings to match the 360 axle diameter. My expectation is that 360 bearings have the same OD as the 650 bearings and will drop right in. I mix and match wheel bearings all the time. That way you get new bearings and nothing is modified beyond return.

Ken
 

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The other solution is to change the 650 wheel bearings to match the 360 axle diameter. My expectation is that 360 bearings have the same OD as the 650 bearings and will drop right in. I mix and match wheel bearings all the time. That way you get new bearings and nothing is modified beyond return.

Ken
 

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Discussion Starter #8
quote:Originally posted by kenessex

The other solution is to change the 650 wheel bearings to match the 360 axle diameter. My expectation is that 360 bearings have the same OD as the 650 bearings and will drop right in. I mix and match wheel bearings all the time. That way you get new bearings and nothing is modified beyond return.

Ken
Genius! I think I'll go this route.
 

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Discussion Starter #9
quote:Originally posted by kenessex

The other solution is to change the 650 wheel bearings to match the 360 axle diameter. My expectation is that 360 bearings have the same OD as the 650 bearings and will drop right in. I mix and match wheel bearings all the time. That way you get new bearings and nothing is modified beyond return.

Ken
Genius! I think I'll go this route.
 

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one caveat


very doubtful you can remove wheel bearings from either wheel and they still remain serviceable

a 360 swingarm does well to fetch beyond scrap metal price
 

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one caveat


very doubtful you can remove wheel bearings from either wheel and they still remain serviceable

a 360 swingarm does well to fetch beyond scrap metal price
 

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HackA,
I have removed many wheel bearings from CB350, VF750, FZ600, etc. that were reusable. However, bearings are cheap and I use new ones if the old ones are the least bit suspect.

Ken
 

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HackA,
I have removed many wheel bearings from CB350, VF750, FZ600, etc. that were reusable. However, bearings are cheap and I use new ones if the old ones are the least bit suspect.

Ken
 

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Discussion Starter #14
After doing some measuring and research, the cj360t uses 20x52x15 left, 17x47x14 right. The cb650 uses 20x52x15 for both bearings. I'm assuming all I would need to do is replace the right bearings with a 17x52x15, or should I replace both with 17mm IDs? Regardless, I'm having trouble finding this size. Does anyone have a favorite place to buy bearings from?
 

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Discussion Starter #15
After doing some measuring and research, the cj360t uses 20x52x15 left, 17x47x14 right. The cb650 uses 20x52x15 for both bearings. I'm assuming all I would need to do is replace the right bearings with a 17x52x15, or should I replace both with 17mm IDs? Regardless, I'm having trouble finding this size. Does anyone have a favorite place to buy bearings from?
 

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will you reuse a wheel bearing if you have to drive it out by it's inner race?

I won't
 

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Looks like you may have a tougher time with this one than a straight up bearing swap. The CJ360 uses a stepped spacer inside the 6304 bearing to bush it down from 20mm id to 17. It might be possible to just use 2 of the 360 spacers to make the 650 wheel work. It would depend on how much room you have with overall width of the drum. This may require a different solution. I also could not find a 17x52x15 bearing listed.

HackA,
Depends on whether or not I had to get the smoke wrench on it and if the seals are melted. They're hard to use with all that gooey stuff in the balls. It really is a judgment call to reuse bearings, so I visually check them and manually spin them feeling for grittiness and evil. It also depends on how easily they came out and where I had to apply force to do it. All that being said, I have not had a re-used bearing fail on me, but I prefer new.

Ken
 

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agreed that it is a judgment call but academically and technically... anytime a bearing of the type we are discussing is driven either out or in by it's inner race......

is NFG

I suppose if one was pressed in without proper the proper interference fit and did indeed come out easy so there was no chance of denting the balls or races

it would be ok for one's own bike as long as it felt good

but

I'll have to say I've seen plenty of bearings...... even new ones...... that failed because somebody did not realize the proper way to handle or not handle them and what wrecks them

I've looked over several wheel hubs and often wondered why they didn't have an easy slot for a punch to move bearings in and out

some I've built for myself have been modfied, when possible, to leave a slot to smack the bearing out via it's outer race

not many hubs have designs that will accomodate that but there are a few that will

pretty sure we are on the same page and I just wanted to give this guy a heads up on the possibility that merely knocking a bearing out can make it NFG
 

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HackA,
You have hit exactly on my pet peeve for bearings. In most cases, there is absolutely no reason not to provide a means for changing bearings without damaging them. Besides, without a notch or access to the outer race it just makes the job harder. Bearings are wear items and need to be changed. We are on the same page.

In this case, I would suggest going back to the original solution and widening the axle slot in the swingarm.

Ken
 

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Discussion Starter #20
Don't worry Hack, bearings are cheap, I see no reason to sacrifice safety to save $5-$10.

Yes, I think I will go with my original plan and widen the axle slot ~3mm.

Thanks again guys!
 
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