FCR Carbs how good are they

[moogie66]

I am doing up my honda 450r.
higher comp piston
porting head, better springs etc
Web cam
White bros exhaust complete
pro design filter
vortex or Alba ignition

My question is how much better is FCR carb. Why are they better
Eg easier to adjust, smoother
Are they worth the money, compared to jetting up std
Does anyone have or know any power spec comparisons

thanks shaun

[chad502ex]

i think the problem most are having with not being able to provide you enough details on fcr performance is that honestly the fcr in it's stock bore will not provide any performance gains that is measurable on the dyno compared to the stock carb. Even some with slightly increased boring on the fcr (43mm) can only offer a "ride report" that seems to "feel" better with throttle response. It's not until you get an even bigger bore on top of the typical 43mm bore when you'll see positive hp gains that can be dyno measured. In other words, you'll have to get bigger than 42mm (stock) to be able to measure any hp difference on the dyno. You may be able to install a 42mm carb (other than stock) and measure an increase in torque, but that's because the velocity of the charge from the carb is higher than that through the stock carb with the same bore diameter. The FCR will increase the velocity; increase velocity is increase torque. Think of increased hp as an increase in volume. Generally, you get more torque through smaller diameter carbs, and get more hp through larger diameter carbs. If the carb is to big, then velocity falls off sharply and idling become difficult to adjust.

If you really want a fcr that will boost ~2hp or more, try taper boring a fcr 45mm! ;)

hope this helps.

Chad502ex