Need help with carburator on 04 XR400

I have a 2004 XR400. Having trouble with initial flat spot with the first crack of throttle. Knowing that it does not have an accelerator pump in the carburator. Want to know if anyone knows of a modification of the carburator to change over to one with an accelerator pump so I don't have that flat spot.

If you have any solutions for me, please give me a call at (916) 479-5198, my name is Mark or reply to this thread.

Thanks!

Probably too lean, try 158 main and 58 pilot.

I have a 2004 XR400. Having trouble with initial flat spot with the first crack of throttle. Knowing that it does not have an accelerator pump in the carburator. Want to know if anyone knows of a modification of the carburator to change over to one with an accelerator pump so I don't have that flat spot.

If you have any solutions for me, please give me a call at (916) 479-5198, my name is Mark or reply to this thread.

Thanks!

Don't give up on that stock carb yet. Before I switched to my pumper carb a couple months ago, I had the stocker tuned about as good as it gets. I don't see much difference between the stock and pumper now. The pumper starts a lot easier, and has just a hair better throttle response. It's enough better that I'll keep it, but if you take a little time to tune the stocker, you can get it really close.

Post your mods to your bike, air cleaner, exhaust, and the elevation you ride and will try to help. I should mention I upgraded my California XR400 to the A16A needle. I think that makes a big difference. If you don't already have it, I highly recommend it.

turn your idle up high to about 1,500 rpm's or so not to a point where the bike is screaming but to a point where the idle is as high as you would want to comfortably leave the bike idleing like that for a minute but not much longer. so now when you let off the gas the engine is still reving enough to create vacuum and pull gas even when you let off the throttle. if your dual sporting the bike just turn the idle back down when you come out of the woods.

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