Raptor stalls downhill.

[Dunk011]

My cousin has a yamaha raptor that has a jet kit(don't know what kind)and a slip on exhaust. He says it runs fine on level ground and up hills, but it wants to cut off coasting down hills. He has rode it for two years with all mods with no problems but now has the stalling problem. has anybody had this problem, and does anybody know where I can find the stock carburator settings or specs online? I've worked on alot of two stroke
carbs ,but never a raptor. I plan on looking at the float,and for trash, but it would be nice to know stock jet size and clip location.
Thanks for any help.
Jeremy

[MadDog56]

Stock jets:

140/145 mikuni mains (left/right)
3rd clip on needle
2/2.5 turns out on fuel screws

[Dunk011]

Thanks maddog, Whats the trick to remove the choke plunger from the carb. It looks like it just pulls straight out, but this one had water and mud in it and the spring that keeps pressure on the plunger was rusted and broke. It will spin, and move back and forth but won't come out. I really don't want to pull on it too hard and break something.
Thanks again,
Jeremy