i'm in the process of -re upgrading my 1990 yamaha blaster with whats in my sig,

what i want to know if you guys can help since i dont know these carbs very well and i was suggested to upgraed in the 30's mm range for more power..

will this carb work?.... Mikuni VM 38 carbureator Yamaha 1993 YZ WR250

if so does anyone know by chance what the jet sizes are cause i can get it prejetted...


please help...
thanks
nathan

 

HERE I'LL MAKE IT EASY

these are the carbs that i'm looking at wanted to know which one may work the best.

36MM MIKUNI YAMAHA YZ 125 CARBURETOR

(( 36MM MIKUNI YAMAHA YZ 125 CARBURETOR))


38mm Mikuni Carburetor Honda XL 350

(( 38mm Mikuni Carburetor Honda XL 350))

Mikuni 38mm Carb, Honda TRX 250r/ATC 250r/CR Honda

(( Mikuni 38mm Carb, Honda TRX 250r/ATC 250r/CR Honda))

38mm Mikuni carb LT250R 250R atv atc

(( 38mm Mikuni carb LT250R 250R atv atc ))
(( 38mm Mikuni carb LT250 250R Atv atc 2 ))

^^^ i really like this one would some one please tell me if this one will work

 

I would say not to go any bigger then a 36. I hear that a PWK33mm is the perfect fit for a 240.

 

you also wouldnt' by chance know anyone that would know the jetting in that carb do you?

 

Nope.
Check out this website

http://www.motocross.com/motoprof/mo...1/carb101.html

that will tell you how to do it REAL easy.

 

sorry, i have read that like 12x's and i can understand that and what mostly should be done but i also had the wrong carb to start. But i guess i kinda wanted the easy way out. or atleast the base line jetting that i should start at with that carb. call me lazy i guess but i have no patience with small working material like whats on these carbs.

 

see if you can find the web site of the company that makes the carb and they might have some charts to give you a starting point.

 

already thought about that....


here is some reference guide for the rest of you.

Main Jet / Slow Jet / Jet Needle / Throttle Valve

PWK 28MM 73R ----- #135 / #38 / 46JJ8 / C.A.3.5
PWK 33MM S46 ----- #165 / #52 / 48CGL / C.A.6.0
PWK 35MM 70R ----- #160 / #68 / 48DGK / C.A.6.0
PWK 38MM 71R ----- #172 / #58 / 48DEG / C.A.6.0
PWK 39MM 72R ----- #160 / #60 / 48DGH / C.A.6.0

Quadvents/Air Strikers
PWK 35MM S65 ----- #160 / #48 / 48DEK / C.A.4.5
PWK 36MM S63 ----- #165 / #55 / 48DGJ / C.A.5.0
PWK 38MM S66 ----- #170 / #55 / 48DDJ / C.A.7.0


this is what i was looking form the start...



information above is from CarbParts.com

 

I would check out Vito's or some other company that specializes in big bore blasters, and see what carb they run. Once you find that out they should be able to give you some info on what they recommend as a base line. As they said on x-files," The truth is out there....."