Thumb Throttles and Gear Shifting

Jayaznpride

Member
Region
USA
Being new to the ebike world and owning a Hydra I have a question.

I've been told not to shift gears using the throttle cuz of the strain on the chain and cassette. But, if you give it a little bit of throttle where the motor spins slowly and then shift I don't see an issue. I feel you can in throttle and change gears without peddling. I did this when doing a stationary top speed with the bike and I used only throttle. So my question is this.

If you give it a little throttle where it spins slowly and then shift the gear is this okay to do? I am pretty sure it is but I want to double check.

Also, were the warning of not shifting when using the throttle because most throttles when pressed give basically a 0 or 100% and feathering the throttle requires you to be precise? I changed the hall sensor in the throttle to get a more linear response.
 

theemartymac

Well-Known Member
With a hydra you should definitely NOT be shifting under throttle. You'll chew up your cassette in no time.

The Ultra not only produces a metric ton of torque, but it doesn't shut off instantly. If you inadvertently cause a chain skip during the shift, your power will still be applied for a second or two after you hear it and then react. In that span of time you can definitely begin to damage your cassette or chain. I was sloppy with my ultra for the first few months relying on the electronic shift disconnect sensor too much, and destroyed my first cassette within 500kms. I've gotten 750kms and counting out of my second with a little more care and attention.

It only took a few big skips under moderate throttle to mangle my small cogs, and when I replaced it, there were several bent teeth, and 2 small cracks in the cog itself. You can try and be as gentle as you want, but even at low throttle, an electric motor is pretty relentless with the power delivery. I posted pics here:

 

Merle Nelson

Well-Known Member
Region
USA
Others will come in with a more informed answer to your question (I've only been riding ebikes a couple of months - and those hub motor.) But I have heard of a chair being snapped on a bike running the Bafang Ultra at weaker wattages. That happened when rider came to a sudden incline he wasn't prepared for and did a jarring shift.

I suspect smooth shifting and power usage which aids that are all golden.
 

Merle Nelson

Well-Known Member
Region
USA
Ahhhh, I cross posted at same time as post #2 above.

And hence the wisdom of holding ones tongue. I should just shut up and let more experienced people answer at all sometimes. :)
 

jharrell

Member
My thoughts are if the stock throttle is too touchy (on/off) as Jayaznpride has reported then yeah shifting would be a bad idea, but if it where more controllable then you could do it more safely you just don't have the feedback that your feet do for giving just enough torque to spin drivetrain to shift but not too much to damage things. When shifting you would have to back off the throttle but not go to zero to complete the shift, just like you do pedaling.