Stock carb or 33mm keihin for my setup

[DrywallDoc]

0-600 elevation
Fmf exhaust
Ported stock cylinder
Vforce 4 reeds
Airbox lid removed
66.5mm wiseco piston
32:1 premix

What's the better carb for my setup. what can I expect from each?

 

[MURPH]

It depends on your riding style and where you will be riding. If you ride in tight woods you want the stock carb. If you do alot of wide open area riding you will want the 33 pwk. The stock carb with the fmf pipe is optimum because the power band is very wide and you will have decent power all over but the top end. The pwk 33 carb will give you more top end but make the powerband more peaky and your bottom end will be non existent. you will also have to work the clutch alot in tight spots to have any low end

 

[Blaaster]

Your best bet will be to stick to the 26mm carb, a 28 may give you a little more top end without loosing too much bottom end.
As Murph says any larger the bottom end will be nonexistent.

 

[DrywallDoc]

this blaster will be mainly for trail riding/mx type racing/ and jumps

sounds like my best bet is to stick with the stock carb and upgrade to a 28pwk.

what would be my jetting requirements with the stock carb?

 

[Awk08]

this blaster will be mainly for trail riding/mx type racing/ and jumps

sounds like my best bet is to stick with the stock carb and upgrade to a 28pwk.

what would be my jetting requirements with the stock carb?

stock carb + FMF pipe + mods, @ that elevation, depending on current temps
stock 32.5 pilot: tune per airscrew/pilot DIY in carb section
stock needle on middle clip position
buy 290/300/310/320 mains
start with 320 and plug chop down to tune main jets, DIY in carb section