85 350X carburetor help

[saltydesertrat]

http://wincycles.com/p55/Honda-ATC350X-Carburetor-1985-1986/product_info.html
Has anybody had any experience with this carburetor? I ordered a rebuild kit for mine cleaned and replaced all the Jets, seals, needle and clip, needle seat. It's dumping fuel out the Overflow hose everything looks to be in good shape and clean, the float itself is original and probably bad but if this carburetor is any good I'd rather just get it. My motor is all stock. Stock exhaust also. Thanks for any help.

[floydechoes2000]

In general you want to stay away from Chinese carb copies. Some people have had luck with them, some have not. A 400EX carb is practically a bolt on upgrade with its built in accelerator pump and it's much more readily available new or used. With a 300EX intake on your cylinder head it's supposedly even easier to install but I had no trouble using my existing boots by using a heat gun. There's a lot of info about this swap over on honda350x.com. Good luck!

[350for350]

I had the same experience with mine. I LOVE my 400EX carb.

[Tacky]

Im with these guys the chinese copies are known to give issues, and numbers are not equal as far as jet sizes etc. If your carb is running fuel out of the overflow the floats are hung. They may be bad, or the needle valve may be hanging up, sometimes the baffle if its put in the wrong way can cause that to stick open. I always after working on my carbs and reassembling them I blow Into the inlet for the fuel on the carb with the carb right side up, then upside down. That will tell you if the floats and valve is opening and closing. Easy trick. You may be able to find the floats on partzilla, I have found parts for my 200x there, factory oem.

Never one a 300ex or 400ex carb on a 350x, no experience there.

[wonderboy]

I find that sometimes the needle/float just won't seat right after the bowl has been completely empty (after a rebuild for example). Once the gas is turned on, if gas starts to run out the overflow, try tapping on the carb body with a screwdriver handle. Sometimes this is all it takes to jiggle things free and allow the needle/float to work properly. Obviously, this only works when there is nothing else wrong like a bad needle or leaky float.

[Ranvier]

I think this happened to me today when I put on a fresh carb rebuilt by flyingW and gas came straight out the overflow. I picked the back end up and dropped it and it stopped and ran great all day.

[saltydesertrat]

Because the price is so good I went ahead and got one of the win racing carburetors. It ships super fast looks great, mounted up easily, started right up and runs great. Jetting seems to be spot on.

[floydechoes2000]

That's cool, glad it's working for you and thanks for the feedback! I know I said stay away from the cheap carbs but I do admit I have one on my 84 Big Red and it's worked flawlessly for at least 2 years now.

[ps2fixer]

I'm no carb expert, but I dug around some stuff, and pretty much any "QA" model carb *should* work for the 350x as a direct bolt on replacement with rejetting of course. The 350x is pretty unique for the Venturi size though, it's 31mm. The TRX350D appears to be the same carb venturi size and is carb model QA03A.

The 300EX carb has a venturi size of 29mm, so stock to stock, the 300ex carb would prob work, but I suspect it would be a down grade if you have any kind of mods at all (exhaust etc).

Sadly the 400EX service manuals doesn't state the venturi size in the specs, but it's a QB10A model and the intake clamp is the same part number indicating the head side of the carb is the same size as the 350x carb.

The 450ER 2004-2005 had a QA15A carb with 42mm venturi, really large, but for someone running a big bore kit, this might be a good carb to use.

Newer machines with an unknown carb interchange model would be something like a 2004-2006 TRX350TE, 32mm venturi, but I'm not sure if the VE series carb is anything close to the QA series or not.

Just some random stuff I've researched across service manuals and such. Was hoping there were more details that could be looked up w\o having to have one on hand to measure sizes and such, so I gave up after 24 machines or so.

Fun thing to note, a 250es/sx carb is nearly identical to the 350x carb, both are QA series, of course the 250 has a smaller venturi (27mm), and the jetting would likely be very lean for the stock jets.

Anyway, yea if the carb is flooding over, first thing I do is tap it with something, generally a screwdriver handle is about perfect size to be enough to shock the float to move, with no damage to the carb. Another thing is, if it didn't leak before the rebuild, you could throw in the old float needle assuming it's in good shape yet.

[350for350]

It's been a few years, but I'm fairly sure that the 400EX carb is a little bit larger on the head side. I was able to use the 350X intake and clamp, but I seem to recall that I had to use some lube and force the carb into the intake.

[ps2fixer]

Just an idea, couldn't you use a TRX400EX intake on the 350x head to solve that problem (also easier to find replacements)? Not sure if they are the same bolt pattern on the head side, I'd assume so or similar though.

[floydechoes2000]

No, the 300ex intake fits the 350X head and 400ex carb perfectly. There's something about the 400ex intake that doesn't work on the 350X, I'll see if I can find the reason..