carb needle taper
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carb needle taper
Anyone modify their carb needle with good results? Thx
Re: carb needle taper
The diameter must also have an effect
Re: carb needle taper
I found this pic somewhere awhile back. Has helped me a great deal in learning how different parts of the carburetor behave at different throttle positions
But no, I have never modified a needle...
But no, I have never modified a needle...
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- Wheelman-111
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Re: carb needle taper
Greetings:
Stock Honda needle?
Daytona makes a kit with like 15 or more needles, all very subtly different in taper angle and diameters, although the overall length is about the same. You pretty much need a caliper that measures in microns to tell them apart, and even then you have to be extremely precise in Where you measure. I goofed with this one time, lining them all up and striking some lines a quarter, half and 3/4 of the way up the taper. The differences were Very slight, but apparently folks think enough to make a tuning change or why bother?
On a stock needle, the only thing I believe you could do is remove material, which would have the effect of richening the midrange a little - or a LOT! I'd use fine sandpaper and count the strokes, remeasuring after a given number depending on how much each pass removes. If you're not sure, have an extra needle to replace the modded one in case it sucks.
Stock Honda needle?
Daytona makes a kit with like 15 or more needles, all very subtly different in taper angle and diameters, although the overall length is about the same. You pretty much need a caliper that measures in microns to tell them apart, and even then you have to be extremely precise in Where you measure. I goofed with this one time, lining them all up and striking some lines a quarter, half and 3/4 of the way up the taper. The differences were Very slight, but apparently folks think enough to make a tuning change or why bother?
On a stock needle, the only thing I believe you could do is remove material, which would have the effect of richening the midrange a little - or a LOT! I'd use fine sandpaper and count the strokes, remeasuring after a given number depending on how much each pass removes. If you're not sure, have an extra needle to replace the modded one in case it sucks.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH