2008 yz450 won't start when hot

[2_strokin]

I have a 08 450 would start cold on first or second kick and ran great! but once it was hot and while I was riding the back would lock up and the back tire would start sliding as if I hit the brake. So I tried to hot start it till I had a brooze on the bottom of my foot so I gave up. Tried again later once it cooled off and my foot stopped throbbin. It started first or second kick and ran great again but got hot and would either stall when idling or lock down again. So took it had the valves "done" welp didn't fix the problem I'm back in the same boat again!

Any ideas?

-Hot start isn't working?

-Carb is dirty?

-Timing is off?

-Decompression valve isn't working properly?

Idk anything would be helpful

What would yall check first?

[NitrousR1]

I'd start by checking the hot start. Start the bike with the choke on and pull the hot start lever. The engine should rev up. If it doesn't rev then It isn't working

[grayracer513]

I'd start by checking the hot start. Start the bike with the choke on and pull the hot start lever. The engine should rev up. If it doesn't rev then It isn't working

 

A little like a thumb throttle, yes.  Fool proof test.

 

That's also a good way to clear any water from that passageway after a wash so as to avoid having the hot start stick in place from corrosion.