I been messing with my Carb (stock Keihin) ever since I got my R and instead of trying to fix it I just figure I'll get a new one. It leaks gas everywhere and has a real hard time idling. What is the biggest I could go, my bike is ported has and FMF fatty pipe and K&N filter with boyseen reeds. Do you lose bottom end torque going big on the carb. Thanks.

 

What kind of riding do you do? GENERALLY speaking, the bigger the carb, the better the top-end (while sacrificing some bottom end). If your riding mx or woods, 38mm would be MAX, IMHO. 36 or 37 would be a better choice (more bottom end and crisper throttle response). Keep in mind that the reed cage has a large effect on the performance also. Try to choose the correct type of reed cage for your application.


lump-dog, esr

 

I would suggest a 35mm PWK or 38mm Lectron if you want any low end. I have the Lectron and it performs great!
ERIC

 

I just got a 38mm Keihin carb for my R. I can not find a throttle cable anywhere in Oregon. Does anyone know where I could order one on-line or anything? Also trx250rob, my friend and I both just got 38mm carbs and they kick ***. I've been borrowing a throttle cable and it just got taken back. I need a new one bad.

 

Try anyone who carries Motion Pro cables.
ERIC

 

Motion Pro cable part numbers:

Stock thumb throttle to "aftermarket" Keihin carbs(other than the stock Keihin carb) part number 021-910

Motion Pro "turbo" twist throttle to "aftermarket" Keihin carb part number 021-912

Magura "Duo" twist to "aftermarket" Keihin 657-902B

For MX and aggressive riding I reccomend using a 35mm PWK bored to 36mm's or for a more experienced and very aggressive rider, a ported engine, a 38mm Air Striker. Big bore for MX gets the 38 A/S too.

38mm Air Striker for ported 250-295cc engines in the dunes. 250-295 hillracing and drag racing 39.5mm Air Striker(bored version of 38mm).

For big bore(310cc+) for dunes 39mm PWK, for hillracing and drag racing 40mm+.

 

i just called on that part number 021-912 and they said it's to short???

 

i called a honda dealership though. also, i have a stock thumb throttle.

 

Stock thumb throttle to a Kiehin PWK you would use a 021-910

 

the honda guy just called me back and said that was the right part number, it just wasn't in his computer. thanks alot for your help.