Need atv help guys!!

frank93 · Mar 16, 2011

My yfm350er

i rebuilt carb and got it running, but it chokes out when i give it full throttle!!

I know it is a carb problem but dont know if its fixable or if i need to buy used working one!

Also when i shut the atv off it back fires!

beastlywarrior228 · Mar 16, 2011

sounds like too much fuel

frank93 · Mar 18, 2011

i took off the spark plug and it was it black

duneracerweston · Mar 18, 2011

Yep over fueling has it been rejeted? Modded? Rebuilds can be put to bether wrong from the factory id check main jet sizes or air fuel mixture screw seting

jarheadoo7 · Mar 18, 2011

Sup number 3..

if your already getting too much fuel .. try ryunning it with out the airbox/remove the header and run it like that. it will be loud but a lot faster!!

jgray44 · Mar 18, 2011

jarheadoo7 said:
Sup number 3..

if your already getting too much fuel .. try ryunning it with out the airbox/remove the header and run it like that. it will be loud but a lot faster!!

That makes me wonder, my plug is also black so I wonder if I just remove my airbox lid if it would help?

jgray44 · Mar 18, 2011

Anyone?

duneracerweston · Mar 18, 2011

It should dose the plug have a lot of carbon on it? Is so that plug might not be the best

jgray44 · Mar 18, 2011

I just put a brand new plug in it so its clean right now. Ill take the lid off and run it for a bit to see what happens

DeadLastRacing · Mar 18, 2011

How black is black on your sparky? I doubt just the extra air will make up for it if its extreme.

jgray44 · Mar 18, 2011

its black but not realllllly black, i mean there is carbon on it enouhg to make the bottom of the plug black. hard to explain, ill send a pic nextime im with my quad i still have the plug

DeadLastRacing · Mar 18, 2011

you want a nice burnt brown color.

jgray44 · Mar 18, 2011

K took the lid off and started it just to see how it would idle and everything seems fine. I won't be able to ride until tomorrow, what's a good amount of time to ride before I check the plug? And should I wait for the motor to cool down before taking the plug out to avoid stripping the threads in the head?