Carb question 1985 honda 350x

[Jackrwesty]

Hello, I picked up a 350x locally and the idle was a little bad on it so I realized the carb was a cheap aftermarket one. I asked the guy for the original and he gave it to me. It was all clean and good but the idle screw /spring was really twisted and fraying, so that's gotta be why he swapped it. Is there anywhere where I can get a new one of those idle springs? I'll try to post pics but idk if I can here or not, I can email or text you pics! All and any help would be great!!! Thanks!!264011264012264013264011

[muthey]

if the aftermarket carb looks like the original take the idle screw from it which is what I did with mine

[350for350]

That spring was broken on mine so I put a 400EX carb on it. From my limited research, I couldn't find a replacement.

[Jackrwesty]

That spring was broken on mine so I put a 400EX carb on it. From my limited research, I couldn't find a replacement.


I have heard about this, what will I need to do to get this to work? Is it a straight swap, or will I need to get new boots? Re jet? Anything? Thanks!

[350for350]

You probably should get 400EX boots. I didn't. For the engine side, I used a small wire wheel on a drill to remove a small amount of material form the inner diameter of the boot. Then I lubed the carb and boot and forced the carb into the boot. For the air box side, I gently heated the boot up to soften the rubber. Then I lubed that side of the carb and slid the boot over the carb. after both boots were on the carb, I tightened the clamps and let it all sit overnight to help relax the boots so they would hold their larger shapes easier. It seemed to work for me anyway. The next day, I put it all back on the trike. As for jetting, since I didn't change anything other than the carb, I swapped the 350X jets into the 400EX carb. Be sure to set the air/fuel screw to the 350X setting. You should at least get the clamps from the 400EX that go over the boots where they clamp to the carb. I was too impatient to get it running again so I used automotive hose clamps instead. It doesn't look real good, but it works. I can't see the clamps while I'm riding.

[BOB MARLIN]

I don't think that carb is "all clean and good". Take that thing apart completely and clean everything. Make absolutely sure all the jets and holes are cleaned out with a piece of wire. The jet with the sideways holes always seems to be the worst. Make sure all those holes are clear.
I have a parts bike that smokes so bad from being completely wore out but still starts on 3rd or 4th kick and runs and idles---as long as the carb is clean.

[oldskool83]

400ex OEM carb upgrade. I did one awhile back also. Just do not use the cheap chinese carbs.