Just purchased a 1971 CT1 for $400, it does run and goes through all the gears.  Came with a third party carb and it may not be the proper one, as there is a 1/2 " gap between the carb intake and the air box tube, see attached photo.  

Do they make a valid 3rd party carb for a 71 CT1 or do I need to run down an OEM carb, and if so, best source for a stock carb?

Thank you.

hosting.photobucket.com/images/i/jbauerman/20221125_201707.jpg
 

Pics are being a pain lately. Is there a way you could add a plastic tube or something to bridge the gap. Or space the carb back to to the filter box tube. Depending how original you want it i guess. Half inch is a fair distance. Don't think the original carb flange sticks out far so is it possibly the wrong airbox boot. Hope you get pics working, or link us to a pic hosting service to load them. I'm a bit technicaly challenged with how to do it. Used to use Photobucket untill they started charging, now half my pics are faded so can't use them. Anyway--good luck. I have a 1970 AT1 but now sprouted a175 top end.
Welcome from NZ if you're new.

Greetings from Tennessee. 

Thank you!  I added a link to a pic, hopefully that works...

Jared

 from Salisbury, UK.

Original carbs, in various conditions, do appear on fleabay.

As it happens, I have this on fleabay at the moment. For a fellow forum member, and because I've had it for a while, it's yours for £75 (about $90) inc postage, if you want it (contact me here, don't buy via fleabay). Do check fleabay in the US first, just to make sure that there isn't a better value one there.

Yamaha AT1 CT1 carb carby carburetor carburettor 248-14101 | eBay

I'd buy the original carb from Alan (G8UNCLEAL), if he's selling it you can be assured it's not junk.

Here's the jets and parts numbers.  AT1 and CT1 did have the same specs.  That changed in 1972 with the reed valve.  There were revisions to the later model (reed valve) jetting.  I think this chart might show updated specs and some original AT2/AT3/CT2/CT3 carbs may have had different jets.  AT1/CT1 specs should be same as in chart.

yamaha-enduros.com/index.php/forums/attachment/55204

Alan,

I did see this one on ebay here in the US, this look like the right model?

postimg.cc/2qJDdyyF
 

Looks like the right shape.

It should have 248 stamped on it, as shown in the second to last photo of my fleabay listing.

Thanks again Alan.  Asking the seller now about the 248.  Appreciate all the help.

Jared