there a 40 and 41 on ebay right now

 

<div class="FTQUOTE"><begin quote>Originally posted by: nimbh2

if does couldnt i just put a 13 tooth sprocket to make up for it</end quote></div>

sorta, but you need your quad to really rev out to take advantage of the big carb. Normal rpm ranges don't require that big of a carb. So to even get the HP back that you lost by using such a big carb, you'll need to rev out that much more. The only reason to ever use a big carb would be because your engine cannot rev out with a smaller one and develop full power. At low rpms, you don't need a 41mm hole for air to go thru without restriction. The question is: At what rpm does a 41mm hole become necessary? 9000? 10,000? 20,000??? Can your quad even go that high?

 

<div class="FTQUOTE"><begin quote>Originally posted by: nimbh2

there a 40 and 41 on ebay right now</end quote></div>

Cool, I'll try to remember that. I've heard good things about the fcr's.

 

then maybe i should sell it and get a fcr 39mm

 

ooops it is a 39mm i looked at it wrong my bad

 

<div class="FTQUOTE"><begin quote>Originally posted by: nimbh2

ooops it is a 39mm i looked at it wrong my bad</end quote></div>

I was wondering if you did... [img]i/expressions/face-icon-small-smile.gif[/img]

 

i just won a quick shot pump off ebay cheap that should help ya think and those 40 and 41mm seems to be coming off the honda 450r dirt bikes.

 

A pump is probably a good idea, especially with a regular carb,,, but a CV carb... not so sure. CV carbs are for smooth throttle response, not really acceleration. I think FCR's are CV carbs.

 

its a flatside i believe.

 

The shape of the slide doesn't have anything to do with it. A CV carb has a butterfly valve that lets engine vacuum go by and suck the throttle open by means of a diaphragm at the top of the carb. All you do is open the butterfly valve with your thumb. So, you can open the butterfly valve as fast as you want,,, the speed of light even,,, and the engine wont bog because the engine vacumm doesn't open the throttle until its ready for it. Therefore, why do you need an accelerator pump? A regular carb may need a pump because you control the throttle directly with your thumb. If you open the throttle too quickly, it will bog the engine because gas can't get in the mix as fast as the air does. Therefore, you may need a pump to help out when you goose it.