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slowhand · 03-09-2022, 09:46 PM

So it seems that I'm about to get a master's degree in scooter CVT transmissions. %$^* it!

My new 150cc scooter tops out at 40 mph & I'm not a happy camper. I'm trying to sort out how to get another 15 mph out of it...

I found the following from an informative webpage:

https://modernvespa.com/forum/wiki-c...to-improve-it-

"One of the biggest misunderstandings is that changes to the variator, clutch and contra springs, and the weight of the rollers will increase your overall power, or top-end speed. This is incorrect, what these changes do are to make the power more useable by allowing the engine to maximize its RPM while it is accelerating, and maximize the speed the engine is revving at when it hits the highest gear ratio available. To optimize the scooter's performance the engine needs to be running at its maximum torque output consistently while accelerating (which on most scooters is somewhere between about 6500-8500 rpm's as this is the level where the 'power band' is at its highest). The whole point of the CVT is to keep the engine at the most efficient RPM by making the gearing variable, the CVT adjusts the gear ratio to maintain that optimum RPMs. Top speed will be achieved when the maximum horsepower hits the limits of drag (friction and air resistance)."

Is it true that the power band in my nifty new 150cc scooter is somewhere between 6500 & 8000 RPM? I'm concerned because my scooter maxes out at 6000 RPM. Which means that my scooter isn't hitting the power band.

Major Bummer.

Or is the point here that my engine's max RPM is being limited to 6000 rpm (out of the power band) by a poor choice of CVT components &/or combination of CVT components by the manufacturer of my nifty new scooter?

I really DON'T want this education.

Thanks all.

03-09-2022, 09:46 PM	#1
slowhand Join Date: Mar 2022 Posts: 26	CVT Eductation (That I Don't Want) So it seems that I'm about to get a master's degree in scooter CVT transmissions. %$^* it! My new 150cc scooter tops out at 40 mph & I'm not a happy camper. I'm trying to sort out how to get another 15 mph out of it... I found the following from an informative webpage: https://modernvespa.com/forum/wiki-c...to-improve-it- "One of the biggest misunderstandings is that changes to the variator, clutch and contra springs, and the weight of the rollers will increase your overall power, or top-end speed. This is incorrect, what these changes do are to make the power more useable by allowing the engine to maximize its RPM while it is accelerating, and maximize the speed the engine is revving at when it hits the highest gear ratio available. To optimize the scooter's performance the engine needs to be running at its maximum torque output consistently while accelerating (which on most scooters is somewhere between about 6500-8500 rpm's as this is the level where the 'power band' is at its highest). The whole point of the CVT is to keep the engine at the most efficient RPM by making the gearing variable, the CVT adjusts the gear ratio to maintain that optimum RPMs. Top speed will be achieved when the maximum horsepower hits the limits of drag (friction and air resistance)." Is it true that the power band in my nifty new 150cc scooter is somewhere between 6500 & 8000 RPM? I'm concerned because my scooter maxes out at 6000 RPM. Which means that my scooter isn't hitting the power band. Major Bummer. Or is the point here that my engine's max RPM is being limited to 6000 rpm (out of the power band) by a poor choice of CVT components &/or combination of CVT components by the manufacturer of my nifty new scooter? I really DON'T want this education. Thanks all.
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