I have looked at a bunch of brochures, Mecum pics, general photos and have found a conflict of whether the carb was painted black or not. The sales brochures show now paint, with many used bikes, including the one I have with a carb that is painted black. My interest is completely factory, NOT a preference. So, question is, what IS factory for the various regions? My interest is USA scheme. Thanks for any help.

As The Rolling Stones would say “Paint it Black” for 1975-76 DT250’s & DT400’s the carburetor was painted black, I am sure on those years and models for the U.S.A. models. I believe other years and models were also painted black but I am not familiar with those.
When you see those bikes with natural finish carburetors it is from them usually having the carburetor rebuilt and dipped in a chemical carburetor cleaning solution, which in turn strips the paint off.

Did you see the pic I posted? It is not a rebuild but factory advert pics...

No, I do not see any picture?

Link to brochure sight

davesbikebrochures.weebly.com/dt400.html

My USA 75 DT400 was purchased from the original owner and the original carb is painted black. I have seen the sister DT400 that his cousin bought on the exact same day, and it also has the original black painted carb. I would imagine the 76 DT400 would've been the same.

I am trying to acquire the sister bike. It is in horrible condition with a busted transmission. But the owner thinks his nephew might want to fix it up someday. Time for me to try again.

Well hard to argue with those pictures, I will say I have never seen a natural finish carb on those models, Yamaha is known to make lots of changes throughout the production runs.
I have owned probably about two dozen 75-76 DT250-DT400’s I bought my first 1975 DT400 in 1975 then I bought a 1976 DT250 in 1976 I am the second owner and I still have it to this day it only has 600 something miles on it to this day, and the carburetor is painted black.

It is possible that Yamaha had a service request upon assembly that required dealers to paint? The quality of the paint, extending to cable on slide makes me think this is possible. Who knows, just want it original. Paint may be better for long term but masking and details when restoring are complicated.

There is an understanding here in the UK that the bikes shown in marketing brochures weren't necessarily the same as the bikes that were actually sold. Might a brochure have been released in order to obtain feedback for certain minor changes? I don't know.

What we need is a couple of ex Yamaha factory employees to join the forum!

It's that way everywhere... brochure photos were almost always taken of "pre-production" models. They needed to be, especially back then. It took time to layout and print. And the promo photos often don't match the details of the final production models.

You can often find "artistic" differences in marketing photos too... even today you'd be hard pressed to find a Ford brochure that shows the radio antenna.