34mm carb?
- Thread starter Racer.Z.
- Start date
Oil block off does not affect power. A 34mm seems rather large for a stock motor. Might help top end power, but it will hurt low and mid range. You want the airflow in the intake to have a high velocity. Q=AV. (Mass flow rate = Area * Velocity) If the area increasesthe velocity will decrease.
LMAO^(motoman)^^ A 34 is too big for a motor that isn't at least ported or a BB. A nice Keihin 28mm PWK or OKO 30mm would be very nice tho.
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Yes you do need it. It's always better to look at power increases as a need instead of a want haha.
i had a 36mm on my crate with an FMF exhaust and boyesen reeds and no lid.............
it SUCKED. it was almost hard to get rolling, and by the time it caught up with itself, it was out of where the pipe made power. powerband was about 1000ish rpms, not usable.
a 28-30mm would be great on your setup right now, and really good in the low/mid on the 240
a 34mm would be a good choice for your 240 kit.
it SUCKED. it was almost hard to get rolling, and by the time it caught up with itself, it was out of where the pipe made power. powerband was about 1000ish rpms, not usable.
a 28-30mm would be great on your setup right now, and really good in the low/mid on the 240
a 34mm would be a good choice for your 240 kit.
You're on the right track, thinking ahead to what your eventual goal will be. More people need to exercise this train of thought more often. A well planned engine will outperform (and more importantly) outlast a cobbled together piece of junk.
If you start to think about your eventual goal and your eventual budget, you'll have a well built machine that will last a lot longer.
A 34mm carburetor on a stock engine isn't going to cut the mustard. It'll have poor low end power because, as motoman pointed out, you'll lose intake velocity. Intake velocity is required to induce the vacuum in the carburetor throat used to draw the fuel up from the float bowl. Too small a carb and your top end is limited by the throat diameter and how much air can rush in through it. Too big a carburetor and you have a real laggy bottom end and can potentially burn up your engine with fuel starvation.
If you find a really good price on a 34 mm carburetor and you have a 240 kit waiting in the wings, put the carburetor on the shelf with the 240 kit and hold onto it. Once the BBK is on, the carburetor would work beautifully.
If you start to think about your eventual goal and your eventual budget, you'll have a well built machine that will last a lot longer.
A 34mm carburetor on a stock engine isn't going to cut the mustard. It'll have poor low end power because, as motoman pointed out, you'll lose intake velocity. Intake velocity is required to induce the vacuum in the carburetor throat used to draw the fuel up from the float bowl. Too small a carb and your top end is limited by the throat diameter and how much air can rush in through it. Too big a carburetor and you have a real laggy bottom end and can potentially burn up your engine with fuel starvation.
If you find a really good price on a 34 mm carburetor and you have a 240 kit waiting in the wings, put the carburetor on the shelf with the 240 kit and hold onto it. Once the BBK is on, the carburetor would work beautifully.
yeah, good advice above..
I run a 34 m Keihin PJ with almost stock bore, but it reflects the porting job.. ive ported the s**t out of my stock cylinder and the switch to a pj 34 was great, but only cuz of porting, different intake and different exhaust..
quoting from a porting book, your carb size should represent about 30 percent of your port area.. so if you ever have your cylinder off, measure the area of your intake ports, divide by three, and then calculate what that translates to in terms of carb diameter.. like pie*rsquared gives you the area of a circle (your carb), re arrange that to get r knowing the area, multiply by 2, and voila, your carb size..
this is to help damp out the resonant frequency of the long intake tract (filter to reed cage) you still want the long track for ram air effect, but the frequency is all wrong..
Wiki helmholtz resonator if you want.
j
I run a 34 m Keihin PJ with almost stock bore, but it reflects the porting job.. ive ported the s**t out of my stock cylinder and the switch to a pj 34 was great, but only cuz of porting, different intake and different exhaust..
quoting from a porting book, your carb size should represent about 30 percent of your port area.. so if you ever have your cylinder off, measure the area of your intake ports, divide by three, and then calculate what that translates to in terms of carb diameter.. like pie*rsquared gives you the area of a circle (your carb), re arrange that to get r knowing the area, multiply by 2, and voila, your carb size..
this is to help damp out the resonant frequency of the long intake tract (filter to reed cage) you still want the long track for ram air effect, but the frequency is all wrong..
Wiki helmholtz resonator if you want.
j
Ok so i have a dumb dumb question but i have everything ready to go but the tube that gose to the carb to the reed cage the stock 1 for the makuni is oveusly 2 small so what do i need to put on it that will bult up and fit to the kinin i have
