yz450f help????

You can verify the idle timing with a timing light. See your manual.

huh, couldn't find it in there, ill look again.

guess I had my head up my butt again on sat. I just found it, don't know if it will tell me what I need to see since it idles good buy its worth checking

Well just replaced cdi and coil with a used one and well guess it was a waste of 60 bucks. Back to the drawing board. Guess I'll go over the harness real good and check grounds. Any more input would be greatly appreciated.

well at the risk of talking to myself...I have gone over this bike head to toe...and found nothing so i guess Im going back into the carb...must be the smallest damn piece of dirt

anyone know the symptoms of a worn out wear plate. I got a good bit of wear on bottom corner? I dont think its my problem since it ran fine until I parked it but I don't have time to order one cause I need my bike. Ill be soakin this damn carb tomorrow so hopefully..........:banghead:

Hi tech24, did you end up finding the problem? I am having the same problem with an 07 yz 450. it started and idled but if i touched the throtle the bike would pop miss throw flames and sparkes out the back. i have done everything i can think of new plug, confirmed cam timing, check valve clearances, compression seem normal. ran fine a month ago but now i can't even get it fired up. i kick i and it backfires or blows a big soft flame out the pipe. checked kill switch and cleaned the carb. this has got me stumped. i also have a yz 444 and i started that the same day and it ran like crap and was poping and missing but i reved it to the limiter a couple times and it cleared right up and ran perfectly. i'm seriously out of ideas at this point. can you help me or are you still inthe same boat?

i got it running took everything apart again assembled it all to spec kicked it it was backfiring them it fired so i reved it to the limiter a couple times and it completely cleared up. not a clue what changed but it's running again

thats good news but no I never fixed the problem with mine. After having the carb apart several times I got fed up. I decided to completely rebuild from the ground up. I tossed the FCR for an edelbrock. Im a few weeks away from a rollin chasis with fresh powder coat, all new bearings, tires, pc triple clamps, FC suspension, and scotts stabilizer. I had a valve job and putting a new top end in, all black plastic with custome grafix, new exhaust and whatever else I can dump money into...lol.

Hopefully it runs well when done. Im pretty sure it was a carb issue.

I tossed the FCR for an edelbrock.
That's a step backward.
That's a step backward.

Yeah it probly is but the fcr pissed me off so I figured I'd give it a try. I don't mind a slight performance loss. If its a pile then I'll toss it or sell it on ebay.

I had similar problem/symptom on my yz250 2 stroke. I did like you, carb, compression etc..... i finaly discovered that the crank bearing were shot so the timing on the flywheel would be off when i rev it...

thats interesting, I checked timing with a light and when I could get rpms up it was fine so I guess we'll see.

juste remove the cover on the magneto side and see if their is chaffing mark on the flyweel or play on the crank

Yeah it probly is but the fcr pissed me off so I figured I'd give it a try. I don't mind a slight performance loss. If its a pile then I'll toss it or sell it on ebay.
I just sold an '06 YZ450 carb to another member here who used it to replace an Edelbrock on a 426. He said the bike never ran so good. The carb was 100% as issued stock, too.

Im putting a flywheel weight and cover on so I'll take a look at her then

where is the carb now? do you still have it

I just sold an '06 YZ450 carb to another member here who used it to replace an Edelbrock on a 426. He said the bike never ran so good. The carb was 100% as issued stock, too.

Damnit don't discourage me...lol. I've talked to a few people on here that have eddies and they are happy. I always gotta learn my own lessons. Hpefully she runs ok.

where is the carb now? do you still have it

I still have it, probly going on drag quad after some repair and mods.

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