250-500cc WR 300 Jetting

[esweetland]

Does anyone have any suggestions for re-jetting my WR 300 with stock Mikuni 38mm carb? I live in Indiana were the elevation averages 800' msl and ride mostly single track trails. I love the bike but it is a beast to start during the its initial start for the day. After that first start, I usually can start the bike with two kicks. I am assuming that I need a larger pilot jet or may a whole JD jetting kit.


Thanks for the advice.

Ed

 

[Dirtdame]

I used the JD Racing kit, but went to a smaller pilot jet and a larger main jet with it. I ride at 3500-5000 ft elevation most of the time.

 

[Zomby woof]

I would like to know what the stock jetting is, if anybody knows.

I want to put a TMXX back on my (2011) 300, but it came off my 150, so it needs to be set up

 

[Dirtdame]

I would like to know what the stock jetting is, if anybody knows.

I want to put a TMXX back on my (2011) 300, but it came off my 150, so it needs to be set up

80 starter jet
35 pilot jet
#4 slide
GAY needle (can't remember what clip position)
R8 needle jet
420 main jet

 

[Zomby woof]

Thank you DD

 

[Dirtdame]

Thank you DD

I think that the pilot jet might have been larger in the beginning, like a 40 or 45, but most people found that the larger sizes were too rich.

 

[shawbagga]

45

 

[esweetland]

Thanks

I will try a JD jet kit for the stock Mikuni

 

[Dirtdame]

Thanks

I will try a JD jet kit for the stock Mikuni

I ended up using a bigger main jet with the JD kit. I went up to a 440.