I agree that a CVT may not provide a more preferrable ratio than one of the 10 gears in a 10-gear cassette provides. However, a CVT is smoother shifting (THE selling factor), even when the rider is stopped. An internally geared hub can shift independently of chain speed, but can only offer limited ratios for your dollar. Imagine cranking along in top gear when that car passes you then turns right without a blinker. With a CVT, or an internal hub, you can drop to "first" with minimal effort. Then again, a CVT is not for a hardcore rider. Just like race-car drivers run manual transmissions, a CVT is for someone who does lots of braking and accelerating (commuters, riders in hilly areas), not Lance Armstrong.
Originally Posted by MichaelW
Does the rider control the gear ratio or is this auto-shifting?
If you are doing auto-changing system , then a dial to set the shifting criteria would be useful. You could set it by pedaling cadence or by pedalling force. Some people like to twidle, others prefer to mash the pedals.
That is very useful input. These are the kinds of opinions I am looking for in order to choose the most consumer-preferrable design. Thank you. However, since I only have 2 more months to work on it (graduate in May), I have to keep things simple, and in my scope of ability. For now I'm thinking of keeping the shifting in the hands (no pun intended) of the rider. That way, they can just twist or "lever" as they crank up the speed, and control their cadence if they wish. Personally, I like to stand up on the bike when I leave the light, but that's probably just 'cuz I ride a 1-speed.
If you're still following along and haven't taken the 20-second/5-question survey yet, please help me out so I have some data for my report on why I picked my design.
shifter survey
Thanks, you guys are great!