Yfz 450 running problems need help

[yfz450lover]

i have an 05 yfz 450 and when i got it i was told it needed jetting for a full curtis sparks exhuast after it had a fresh rebuild with a wiseco piston 12:1 compression. it spits and it used to spit flames. so i bought 180 main jet and 45 piolt. it helped queit a bit but its a ***** to start and sometimes take alot just to start i need help anything will help. thanks

[yfz450lover]

it also bogs and runs bad in the low gears

[RPM Restorations]

You should check your spark plug and TPS.

[yfz450lover]

any thing else?

[RPM Restorations]

it only runs with the choke on right? u should try just warming it up sometime for like 30 min and see what happens.

[pbsandman7]

What intake are you running? What elevation are you at along with climate temp?
Do you just use the starter or do you blip the throttle a tiny bit while trying to start it?
Have you checked your valve clearances?

[RPM Restorations]

Originally Posted by pbsandman7

What intake are you running? What elevation are you at along with climate temp?
Do you just use the starter or do you blip the throttle a tiny bit while trying to start it?
Have you checked your valve clearances?

He has the kickstart because the electric starter doesnt work.

[nickmell]

Have you messed with the fuels screw any?

[pbsandman7]

If you have a kicker.. its not how many times you kick it, its where you kick in relevance to tdc. If your jetting or valve clearances are off, it will be a b**ch to start either way.
Kickers like a leaner pilot too btw.

[RPM Restorations]

Originally Posted by pbsandman7

If you have a kicker.. its not how many times you kick it, its where you kick in relevance to tdc. If your jetting or valve clearances are off, it will be a b**ch to start either way.
Kickers like a leaner pilot too btw.

He doesnt have the tps hooked up.

[yfz450lover]

if the spark plug is bad will that cause all of this?

[nickmell]

Possibly when spark plugs get old the electrode will get rounded and won't spark as well. As cheap as they are give it a try and see if it helps.

[S1CKLIFE]

sounds like it is flooding the motor at low rpms fuel screw setting might be to rich and 180 main is a little big for any elevation with close to stock motor set needle to 3 with a 170/175 main jet 48 pilot jet 2 1/2 turns out on fuel screw this might fix it I'm at 1000 feet elevation with hmf full exhaust lid off stage 3 cams and jetted to 170 main 48 pilot 2 3/4 turns on the fuel screw and runs perfect.

[nickmell]

I asked him if he was messing with the fuel screw but never got and answer, 180 does sound big I think thats what im runnin but I have a fci with my sparks.

[yfz450lover]

when i jetted it i turned the fuel scew 2 and 1/2 times