Help - what rear wheel did I buy?

Hey guys, so I just bought this on ebay for a pretty good price. Was advertised as an XS650 18" rear wheel, came with an extra rim, and from the pictures I assumed it was correct. Now that I have it and I am tearing it down to clean up, this doesn't seem to actually be an XS650 hub and I'd like to try and figure out how to use it. Thanks for any help.

The sprocket it came with has 43 teeth, the XS650 sprocket will fit on it, and my rear axle fits through it.

So I just found out it's probably from an TX500. I should still be able to use it?

I see no reason to not. You will probably have to get new bearings, wheel spacers, sprocket (if your doesnt fit), and possibly some other odds and ends for the brake linkage.

Thanks, I figured as much, the 650 sprocket fits no problem as well as rear axle. I will get some TX spacers and see what I can come up with.

Yes, that is a TX500 rear wheel. I'm in the process of adapting one right now. The most desirable feature of that wheel is that the sprocket has a cush mount. Unfortunately, the design has a steel insert in the sprocket carrier that slides onto a steel sleeve in the hub. There's a good chance it's all seized up. I needed to use a 3 jaw puller to get the sprocket carrier off the hub. My parts were rusted together pretty good and no cushioning was happening.

The other problem is spacing so that the rim and the sprocket align properly. The 500 swingarm is narrower so additional spacers are needed to fit the wheel into a 650 swingarm. Also, the distance between the sprocket and hub center is less so the sprocket needs to be spaced out some. Now this may seem like a daunting task but the solution turned out to be quite simple. All the spacers required can be made out of the old 500 sprocket. I don't have time right now but I will get some pics up over the next few days illustrating the process.

Great, I was hoping that was the case with the "sprocket spacer". Sound like I will have to tear into it further than expected and see what the condition of the damper mech is. I look forward to your pics.

OK, to get you started, here's a parts blow-up. You have the later style hub that utilizes the sprocket carrier retainer ring (#52) pictured in the inset at the upper right, also it's tabbed lock ring #51. You won't have parts 29 and 30 shown in the main drawing .....



Tap the lock tabs down on 51 and then you can tap the notched retainer ring #52 off. Then the sprocket carrier should pull off if not rusted to the hub. However, here's what you may be dealing with ..... rust on the sleeve and in the sprocket carrier .....





Note the 2 grooves in the carrier. Those hold rather large o-rings that are supposed to seal the assembly. After 30 some years, that may not be so anymore. Try to save the o-rings because even though Yamaha still sells them, they're $6 or $7 EACH. And here's what you may end up with after a proper cleaning and rebuild .....

Now for the spacers. As I said, all can be fabbed from the 500 sprocket. You'll need a spacer ring for the sprocket and 2 small rings for the axle, one on each side of the hub (I cut extras) .....





..... and here's what you'll end up with. The small rings for the axle will be added to the original 500 spacers. I welded one to the 500 right (brake) side spacer, left the sprocket side one loose .....

One more thing - when reassembling, make sure you lather up those steel parts really good with anti-seize .....

wow, thanks so much 5twins! that helps a lot. I assume the threads on the retaining ring are standard 'righty' threads? wouldn't be surprised if they were lefty due to direction of rotation.

Yes, standard threads. The lock ring keeps the retainer tight. Also be aware that the sprocket side bearing is the same as the 650's and uses that spacer inserted from the rear (#19 above). Don't inadvertently throw it away with the old bearing.