Ok, this is copied off partzilla so should be right. CARBURETOR ASSY | DT250A Not Available
438-14101-60-00. I'm guessing the 438/60 you have refers to what's in this part number here. Shows it at the bottom of the page in item 41, complete carb. Important thing too is the very small Oring item No4 if yours has the side mounted main jet. If that leaks she won't rev & like the choke's on if its bad enough.
www.partzilla.com/catalog/yamaha/motorcy...74/dt250a/carburetor

Several people have tried to help and it seems to me the answer was given. Let me summarize and add a Yamaha document.

Yes, that is the carb number for a 1974 DT250A.

Yamaha Tech Sheet shows the same thing.



Yes, you need a 60 pilot according to specs. (DT360 took the 50 and they share parts lists so easily confused)

Go to eBay and buy this jet:



(Above is a Niche Cycle ebay auction... or go to the Niche Cycle site link given before.)

Done.

Or even before doing the above... Why not not help yourself by giving us better information?

What jet did you try to buy that didn't fit? Picture? Part number? Link?

Where are you trying to install it in the carb? Picture?


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