This is probably going to be one of the dumbest questions posted on endless sphere today. If you are using a mid drive motor in your E bike, when you change your gearing while you are moving along, does that change the gear ratio going to the mid drive motor? I’ve built several rear hub E bikes. I’ve also built a scooter and a go cart with a direct drive brushless motor. To change the gearing ratio on those I would need to take off the chain and swap out either the motor sprocket or the wheel sprocket in order to get more torque or more top speed. I’m learning about mid drive motors and want to try that in my mongoose dolomite fat tire bike that I recently bought. I don’t know much about mid drive motors hence the crazy noob question. I’m most likely going to be using lunar cycles 72 V 7500 W mid drive motor. I have no need or desire to use PAS or pedal assist. This is strictly going to be throttle only, no peddling at all. So I’m assuming when I change the gears on my derailleur to go from gear 1 to gear 7 this will change my gear ratio on my mid drive motor and give me more torque or more top speed. Is that correct? Also would it be safe to assume that you wouldn’t have to necessarily change gears at all and just leave it in the 1 or 7 gear? Thanks for any advice.
Mid Drive Motor changing gearing changes gear ratio?
- Thread starter Joecool
- Start date
zro-1
1 kW
The answer is yes and no.
A mid drive motor will always have a fixed gear ratio between the actual motor and the chain ring—that never changes. However, when you shift gears, you are changing the ratio between the motor (and your pedals) RPM and the rear wheel RPM, which for a hub motor would be like changing the gear ratio.
As far as shifting or not, that depends entirely on external conditions. For example, if it's flat where you ride, then you may never have to shift. If it's hilly, and you notice that your motor is bogging down, then you'll want to down shift to give it more of an advantage (just like you do for yourself when you're pedaling and struggle to get up a hill). The key thing you want to do with a mid drive is try to keep it in it's sweet spot so that it runs as efficiently and cool as possible.
Hope that helps.
A mid drive motor will always have a fixed gear ratio between the actual motor and the chain ring—that never changes. However, when you shift gears, you are changing the ratio between the motor (and your pedals) RPM and the rear wheel RPM, which for a hub motor would be like changing the gear ratio.
As far as shifting or not, that depends entirely on external conditions. For example, if it's flat where you ride, then you may never have to shift. If it's hilly, and you notice that your motor is bogging down, then you'll want to down shift to give it more of an advantage (just like you do for yourself when you're pedaling and struggle to get up a hill). The key thing you want to do with a mid drive is try to keep it in it's sweet spot so that it runs as efficiently and cool as possible.
Hope that helps.
