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DannoXYZ · July 4th, 2022, 02:31 PM

Note jetting for pre-gen bikes is completely different than new-gen. There's two performance variables you may be able to distinguish:

acceleration - function of torque vs. weight. IF bike had factory-level output, having lower gearing would give you better-than-factory acceleration. As baseline, factory bike did 0-60 in about 7-sec. If your bike can't match or beat factory speeds, it's not gearing issue.

top-speed - function of power vs. aero drag. Max-power is generated at about 11K-rpm, so you'll want to select gear that places RPMs right in that range to coincide with top-speed.

What RPM and gear are you in when you hit your observed top-speed? Even IF your bike was geared lower, you'd still hit 105mph in 6th-gear instead of 5th. Your overly-rich mixture will rob you of about 3-5mph top-speed, not 20-mph.

So I suspect your carbs may need deeper cleaning with scrubbing out of hidden secret passages and bleed holes poking out with soft copper wire. Carb-cleaner spray no longer work due to removal of chlorinated compounds. Might as well use pee as at least it's got some ammonia in it.

I would put everything back to factory OEM bone-stock condition and get some baseline performance numbers for future comparisons. You'll find add fuel will just make bike slower.

I use one of these to measure changes AFR with each mod: http://wbo2.com/2y/default.htm . Max-power is made at ~13,5:1 AFR on NA engines (dashed line on dyno above). And one of these accelerometers to measure actual changes in performance since butt-dyno is hugely inaccurate. Measures 0-60 and 1/4-mile very precisely and actually gives fairly accurate Hp estimates based upon your entered weight parameters.

BTW - you are redlining every gear on way to top-speed right? Due to reduction in on-the-ground torque at contact-patch with each higher-gear, you won't be able to accelerate up to a speed that'll allow continuted acceleration in next gear if you shift too soon (this chart came from car, but same idea).

July 4th, 2022, 02:31 PM	#7
DannoXYZ ninjette.org certified postwhore Name: AKA JacRyann Location: Mesa, AZ Join Date: Dec 2011 Motorcycle(s): CB125T CBR250R-MC19 CBR250RR-MC22 NSR350R-MC21 VF500F CBR600RR SFV650 VFR750F R1M ST1300PA Valkyrie-F6C Posts: A lot. MOTY - 2018, MOTM - Nov '17	Note jetting for pre-gen bikes is completely different than new-gen. There's two performance variables you may be able to distinguish: acceleration - function of torque vs. weight. IF bike had factory-level output, having lower gearing would give you better-than-factory acceleration. As baseline, factory bike did 0-60 in about 7-sec. If your bike can't match or beat factory speeds, it's not gearing issue. top-speed - function of power vs. aero drag. Max-power is generated at about 11K-rpm, so you'll want to select gear that places RPMs right in that range to coincide with top-speed. What RPM and gear are you in when you hit your observed top-speed? Even IF your bike was geared lower, you'd still hit 105mph in 6th-gear instead of 5th. Your overly-rich mixture will rob you of about 3-5mph top-speed, not 20-mph. So I suspect your carbs may need deeper cleaning with scrubbing out of hidden secret passages and bleed holes poking out with soft copper wire. Carb-cleaner spray no longer work due to removal of chlorinated compounds. Might as well use pee as at least it's got some ammonia in it. I would put everything back to factory OEM bone-stock condition and get some baseline performance numbers for future comparisons. You'll find add fuel will just make bike slower. I use one of these to measure changes AFR with each mod: http://wbo2.com/2y/default.htm . Max-power is made at ~13,5:1 AFR on NA engines (dashed line on dyno above). And one of these accelerometers to measure actual changes in performance since butt-dyno is hugely inaccurate. Measures 0-60 and 1/4-mile very precisely and actually gives fairly accurate Hp estimates based upon your entered weight parameters. BTW - you are redlining every gear on way to top-speed right? Due to reduction in on-the-ground torque at contact-patch with each higher-gear, you won't be able to accelerate up to a speed that'll allow continuted acceleration in next gear if you shift too soon (this chart came from car, but same idea).