Good day all!  
I've run in to a jam with the inspection/ registration with my CT2.  At some point someone has hit something and put a big flat spot on the front rim, which has put the rim out of spec, as far as inspections go.  So, I'm not sure what the best route to go to resolve this issue.  The way I see it, is to either buy an entire "new" wheel OR get a 21" rim laced up to the existing hub.  I *think* the fastest way is to get a new wheel BUT I'm not sure what I should be looking for (" wheels that bolted up to the CT2 and had a speedo cable?  I'm assuming the AT2MX but would appreciate some help on that.  Alternatively, I could buy a 21" hoop and lace it up to the existing 'd have to find a local shop that builds wheels, but that might be a task unto itself.  I've built bicycle wheels in the past, so would not be opposed to trying, but getting the spoke lengths correct and understanding offsets (if any) would be a challenge.  

As usual, I appreciate any advice from the collective.

Also - if you have a 21" wheel in your shed looking for a home please reach out!

Much appreciated.
Shane

I have a 1972 RT-3 with a 19" wheel with a good rim and rusted out spokes. I bought NOS spokes on eBay (~$100); there are aftermarket spokes as well). I had my local shop (Austin, TX) do the lace up and truing (~$200). All worked out well.

if me, I would get 2 new tusk or excel wheels, some SS spokes and self install to save.

Is this a match for your wheel?
ebay link to wheel

Thanks for the info guys.

PABDT - Yes! That's the same rim - I'll need to do a bit more checking to confirm if the hub is the same.

As a brief update, I ordered a 21" wheel/hub assy off Ebay that states it is off a 1975 DT175 (B?).

My plan is to use the rim and re-lace it to my hub. While I wait for it to arrive, I was just thinking it would be really nice if this wheel/hub/brake could be made to work on the CT2. The hub part numbers are different, and from what I can tell, the brake shoes are a bit bigger on the 1975...

CMSNL says the axles are the same; that's a good start.

Does anyone in the community happen to know if the hub from the 1975 DT will mate up to the forks on the CT2? I'm referring to the "spline" that holds the brake plate stationary. That's the most obvious difference between the brake plates, looking at the parts diagrams. I guess the total hub width and rim offset are a consideration but I can't determine any of that without actual dimensions.

I could order a brake plate, but don't want to throw more money at this without knowing a bit more.

Much appreciated!

It's a pretty sure bet that if what you bought was a 21" wheel from a 175, it came from a 1976 DT175 as that was the first year of the 21" for that model.  (1975 was a 19" front on the 175)

Pretty sure you'll be fine on the fitting.  The early steel forks had a narrower "tab" for the brake plate but CT2 and later had aluminum forks with the wider brake slot.  

Yamaha made a LOT of parts interchangeable.  Only thing I'm not sure of is the "height" of the brake tab on the forks but the overall wheel "with spacer and brake plate" width should be identical.  

Be careful with rims because if you had a 21 rim made for a ct2 hub the spoke angles for nipples in the rim should be equal seeing the ct2 hub is a straight hub across. If say for instance you got a rim for a mono dt175 that has a front hub with cotton reel size one side & brake hub full size the other, then the rim for that "should be in theory" less steeply angled for the cotton reel side. More angled brake side etc. Sorry if I talk in riddles a bit. I know what I mean even if others don't lol.

That's encouraging news, MarkT! I'm hopeful that will be the case... then I'll only need to buy a brake plate to sort this out. Much easier than building a wheel.

The Ebay listing stated the wheel was from a 1975 DT175, but I guess that's why I didn't see 21" wheel on Partszilla or CMSNL. I guess it's possible the bike was built in late '75, but is actually a 1976 model year. Either way, thanks for clarifying that. I'll know more when it arrives in a couple of weeks.

Hi RT325 - I agree with you on that. The hub on the "new" Ebay wheel appears to be same size hub flange each side; similar to my CT2 hub. At the end of the day, I'm really hoping to avoid building a wheel and just use the new one. If it comes down to building a wheel, I'll have to cross that bridge when I get to it. Appreciate the heads up!