Hot start lever vs. choke

I have a ‘08 450X. It will not start when hot by using the hot start lever. However, it will hot start easliy by using the choke. Once it starts l immediately shut the choke off. It will then idle and accelerate without problem. Any ideas on what’s up with that?

Hot start allows more air, making a lean condition. Choke restricts air, making it rich.

Sounds like your settings are off, jets, needle clip position and idle adjustment.

I agree with MSFIT. The hot start will allow more air, and it might be that the fuel mixture screw needs adjusted. 

1. Screw in the mixture screw and count the turns in, until it lightly seats. 

2. Back it back out to where it was. Should only really be about 1 1/2 turns. 

3. Warm the bike up for a couple minutes.

4. Pull in the hot start while its idling. It should rev up because it went lean. If the bike stalls it might be to lean.

5. If it does that, open it only about 1/4 turn and try it again.  If you find your more than 21/2 turns out, the you might need to change your pilot jet. 

I dont know if you rejetted the carb. I bought a JD kit for mine and it runs great. Did air box mod and new fmf pipe and header. Never had any problems. only jet I changed was the main to the 170 from the kit. And the supplied needle. Instructions were simple. And also tie the accelerator pump just like it says. Now it starts without using the choke real easy. 

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