05 yfz 450 need help!


hey my buddy rejetted his quad , it didnt run at all after that so we put the jets back to what was in it and got it to run but i runs like crap. We cleaned the carb and when it start and we mess with the idle it dies. there is no airbox lid cuz i has never ran good with it and it has a full system two bros pipe . What should it be jetted at? Or what could it be?

If you run with the stock jetting and you have removed the airbox lid and have an exhaust system, be glad it runs like crap because that will keep you from going out and riding it and melting your piston!

Jetting is done by starting out rich, then backing it down until is just runs a bit lean. Then, you go up one size richer just to be sure you never ever run lean. It is more art than science, and requires patience....but if you want it done right, you need to have it done by an experienced pro!!!

I know how to jet it but that's not doing anything that's why I'm wondering what else it could be

I know how to jet it but that's not doing anything that's why I'm wondering what else it could be

If you really knew how to jet, you wouldn't have asked 'what should it be jetted at', because you would know that you have to change the jets incrementally, then ride it and see what the change did.....not just throw in whatever jets some random guy recommended on some forum!

reconranger seriously just shut the fu ck up! you think you know what your talkin about and you really dont! Just sit on your fat ass in California and be happy I dont know where you are cause if I did I would come there and slap you right in the face for being some fu c kin stupid! And your just some guy on a forum so take your own advice and fu c kin step off! Seriously!

^ :smirk: ^

To the op:

Jetting is your issue, plain an simple, if you have a full exhaust system + airbox lid off, your not pushin enough fuel stock. If i were you, get a K&N filter and put on there, go to your local yamaha dealer, give them your setup and hey should point you in the right direction. I wouldnt buy a full jet kit because they cost alot of money and I have always ended up going and buying single jets to perfect it. Best of luck to you!

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