I posted a recent thread about my newly acquired 75 dt250.
I am having issues with the carb, the latest being the hole for the air mixture screw is stripped.
I searched ebay and seen one pre-owned one for $275!
But I also seen alot of cheap (less than $40) carbs that look like they would work, chinese no doubt...
My question is, has anyone had any success replacing a stock carb with an aftermarket one and have any luck?
I know I had a 75 dt400 carb sitting on my shelf for years, all clean and ready but I'll be darned if I can find it, keep looking I guess.
Any input would be appreciated.
Dan

I was in the same boat as you, when you need one you can’t find them or they are ridiculously priced, I have a thread on here somewhere under my user name where I used a new Mikuni carburetor, I believe it was around $125.00 a couple of years ago, you have to be careful with the Chinese knock-offs as they are hit or miss in quality and working properly. I used the slide and mixer cap off the old carb as they are the tall style vs. all the new Mikuni carbs are the short style, I then installed new proper size main and pilot jets into the new carb as it comes with the wrong size jets out of the box. You have to also have to drill a hole in the spigot mount to install a nipple for the autolube hose, I bought the nipple from Niche Cycle $3-$4 dollars, if you are running premix you can eliminate that step, other than that it was bolt on. If you are interested I have a brand new Mikuni carburetor that is still in the box or I have I believe 2 used original carburetors for the 1975 DT 250, one needs rebuilding and one is already cleaned and rebuilt ready to go, I’ll let them go very reasonable, If you can’t find the thread let me know I might still have the pictures on my phone.

I found the one I knew I had!
It is from a 400 tho.
I know I must have some more bodies around here.

I will keep you in mind.
What is the difference between the 400 and 250?
just the jets?
Dan 

Upon a glance. The bodies are different in size.
Even the top screw cap is different size.
I would have to use 400 reed block and screw cap and airbox boot...

Of the 2 original carbs you have.
One is rebuilt?  What all has been done, new needle and seat?
The important thing for me would be that the tiny little jet down (pilot jet?) in the tube can screw out and in and no other threads are damaged.
Set a price on one or the other and I just may buy one off you.
No hurry, let me know...
Dan

Hey Dan,
  Good question asking about pilot jet. I always ask about the pilot when buying a carb. I've found that if there is going to be a problem when buying a used carb it's usually gonna be a stripped or stuck pilot jet

1975 Dt250 carb has a 498 stamping . Is that correct???

I see 498 on mine.
then it has 61 underneath that
Dan

The rebuilt one has a new needle and seat, new bowl gasket and stock size jets, can’t remember if they are new or used, if they are new they are Mikuni brand as that is the only jets I will use. The other carb has just been cleaned and is ready to be rebuilt, both have good threads on the pilot jet. A stuck pilot jet on the original carb is what caused me to start on adapting a newer Mikuni carb to my bike, and as usual once I didn’t need a carb anymore I ran into some good deals on eBay and decided to buy them for future projects that haven’t happened yet. I am on the road right now and not home yet to verify what I have but I should be home by Wednesday if you want some pictures.

Any chance that the thread can be re-tapped?

498 is the code for the 1975 US DT250B, so sounds correct.