I just completed my first rebuild on my 400ex and when I start it it idles fine but when I ride it and give it gas I just bogs down. The carb is leaking gas from the overflow so im sure the float is sticking. Could this be what is makin it not run properly? I plan on cleaning the carb today and trying that but if yall have any sugestions please let me know. thanks.

 

A REBUILD WITH AN 07 what the heck did u do forget oil?

 

If gas is leaking out the overflow, then you are sucking raw gas into the motor, running way rich and bogging out the motor. DO NOT run it like that long, get that carb off and make sure the needle and seat is clean and sealing, the float is set correctly, and the gaskets are good. Raw gas going into the cylinder will 'wash' the walls, stripping off the oil and causing the rings to score the cylinder walls, your new parts wont last long like that, get that carb up to 100 % before running it anymore, and check your oil to see if the level has gone up, or if it smells 'gassy', drain it and put in fresh immediately.

and MRWONDERFUL.... have you ever heard of someone riding a whole lot, more than normal and wearing out the engine faster? or maybe he bought it used, with a tired motor and wanted to freshen it up, don't just slam post and start blaming him without any facts. He has a legitimate problem, and the fact that he rebuilt an 07 ( 5 hard years of riding could tire out any motor) does NOT mean he abused it.

 

I don't think Mrdude meant anything by that.

But speaking of "smelling gassy"..How ya beem 95wolv?? LMAO

But what he said, seat and needle.

 

This from a guy that sneaks around stealing LT80 tool boxes so guys have to go looking for a new one..........take THAT, Jack......hee hee.

 

The reason I rebuilt it was becaus my timing chain tensioner broke causing it to jump time and it bent all 4 of my valves. I had to do a complete rebuild because my shift drum and forks were damaged so third gear did not work. Any way I took the carb back apart and cleaned it real good and it is running great now. Better than ever. Thank yall for all yalls help.