Do I need a bigger carb?

[rideyamaha09]

My blaster has a high flow air filter, no lid, bored .030 over, and a dynoport exhaust. I'm currently running a 310 main jet with stock pilot and needle clip is on the next to richest spot. When I open it up in 1st through 3rd gear it sputters as I get into the higher rpms. Once i'm in 4th and above it revs fine. Is this a jetting issue or do I need a larger carb? I'm not sure but it seems like i could be emptying the carb bowl in the low gears since it revs quick them. Thanks in advance.

 

[Zwiser]

youd be fine with a 30mm oko heres a link OKO 30mm RACING CARB. FLAT SLIDE CARBURETTOR: eBay Motors (item 180519159954 end time Jul-11-10 06:37:17 PDT)

 

[nd jat]

stock carb is fine, but a tad small for full power on a reasonably stock motor. I'd think the jetting is off. clean the carb first this will get rid of any problems with clogged jets, and check the float height while cleaning. This can cause issues with fuel flow if out of wack. to low carb acts lean to high carb acts rich. than if you still have the same issue change jet settings one thing at a time. Air screw for the off idle throttle, needle hight for mid and main for the WOT. Hope this will help ya

 

[98blasterworked]

hey.... i was wondering if i could even handle a 30mm oko.... mods r in sig

 

[Zwiser]

i think 30mm okos r good for stock balsters (stock cr,kx,yz,rm 125 dirt bikes come with 34 and 35 carbs) so i think a 200 should at least get that stock

 

[nd jat]

125's power is screaming in the rpm range. Blasters power is more balanced thro the rpms. how many 125s have that great of low mid power?? not many that I'm aware of but they are screaming when they're on the pipe for the power. higher wound out motors can use bigger carbs, at a sacrifice to low end power.

 

[Zwiser]

my friend has a 2003 bone stock rm 125 and u can start out in 3rd gear

 

[rideyamaha09]

Most 2 stroke dirt bikes have power valves on them which causes the hard hit of the powerband, thats a major difference in them to blasters which is why blasters seem smoother throughout the rpm's.

 

[nd jat]

power valve gives the best of both lower and higher rpm power with out having to sacrifice the other. power band is more to do with the pipe on the motor, cause of the tunning to rpm ranges for peak performance of the 2 stroke design. When the rpm range of the pipe is met the motor can excede 100% efficiency. hence the power band.

 

[super noober]

have you done a proper plug chop? that would answer it all right there. haev you tried any bigger jets? i could see with no lid and a dyno port you could pull a 320 possibly a 330. i dont really think a bigger carb is needed with ur mods but a 30mm would be nice if you have money layin around lol I:I

 

[98blaster+4]

i have about the same setup and on the stock carb i was running a 320 main and was gonna go up to a 340 or so and then a bud advised me to get a bigger carb for my riding style. so i got a 30 mm keihin pe carb for cheap and when i get my bike back together i ill be running it. i would say to try and find a 28mm or 30 mm carb for your setup and you ahould not have any bogging issues after the switch as long as you take the time to jet accordingly. but if you want to test to see if your lean put the lid back on the airbox and try it out, if it runs real good with it on then you need to up your jet size.
hopefully my rambling has helped steer you in the right direction.