Why don't you pedal your ebike?

Im somewhere in the middle. I pedal 100% of the time but with little torque. I personally dislike the feeling of not pedaling, maybe its years of regular cycling whilst i was healthy thats ingrained into me that my legs need something to push against. If however my battery failed, id be stuck. I can barely pedal a regular bike these days with my joint arthitis, never mine with my 16" moped tyres. I put these on so i never have to worry about punctures again.
 
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I’d love to add some pedal-ability or even resistance but can’t figure how. With freewheeling cranks I see no possibility
 

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yantra yatra said:
I don’t pedal because chainring is too small and programming wrong on the current Bbs02 I’m using. The programming is too aggressive to keep up with pedalling and also the natural spin speed of the motor isn’t so conducive to actually pedalling. I absolutely prefer to pedal (a lot) but torque sensing makes it much more enjoyable and having the right gear reduction ratio is very important imo
Click to expand...

Have you looked into using shorter cranks?

The smaller pedaling circle of the shorter cranks makes it easier to get higher rpm. You have to raise your seat though to compensate for the fact your pedal when in the 6 o'clock position is higher than it was before.
 
..that results in a small worsening of center of gravity, which you really want to optimize on an ebike if handling matters.

The core problem is ideally fixed with a larger chainring, controller programming, or lower battery voltage, depending on the cause of the problem.
 
neptronix said:
..that results in a small worsening of center of gravity, which you really want to optimize on an ebike if handling matters.
Click to expand...

Not necessarily. If raising the seat is accompanied by keeping the handlebars at the same vertical height the center of gravity won't change much if at all. This because rider position is changing from one that is more upright to one that is more aerodynamic:

Does crank length matter?

Crank length can be used as a tool to improve fit related issues impacting comfort, power, and aerodynamics.
rotorbike.com rotorbike.com

1733696346191.png
www.cyclingweekly.com

What's the optimal crank length for you? How to calculate the best setup

If crank length is too long you'll suffer hip, knee and back pain. Get it right for better bike handling, aero gains and pain-free rides
www.cyclingweekly.com www.cyclingweekly.com

1733697031641.png
 
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Yes, but it will change and so will ability to touch toes to the ground without getting off a bike on a stop.
The more you shorten the cranks, the higher you have to go upwards.
If you are not in an aggressive position already ( most ebikers aren't ), and more upright, your aero might get worse.

There's a price to pay for the change, so it's not a no brainer.

Has anyone won a race with shorter cranks or measured an aerodynamic difference?
Have you tried it and proven it?

The above article is good but doesn't quantify the aerodynamic aspect at all or cite any sources, which is a bummer.
 
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neptronix said:
Yes, but it will change
Click to expand...
Only if a similar riding position is used (i.e. handlebars are also raised an equivalent amount).

If a person does not raise the handlebars the torso assumes a more horizontal position than it did before and thus the center of gravity of torso lowers at the same time center of gravity of lower body raises.
 
neptronix said:
Has anyone won a race with shorter cranks or measured an aerodynamic difference?
Click to expand...

Read about the hour record in post #31.

Some more information gained by wind tunnel testing:

speedandcomfort.com

Crank Length

How Low is Too Low? This was one of the first reasons that we explored the shorter cranks. While developing faster rider positions in the wind tunnel, it was quickly apparent that many riders needed to get lower in the front but simply couldn’t because of upper thigh / stomach interference...
speedandcomfort.com

1733700756755.png
 
My BBS-02 bike's seat is too low,
ebike4healthandfitness said:
Have you looked into using shorter cranks?

The smaller pedaling circle of the shorter cranks makes it easier to get higher rpm. You have to raise your seat though to compensate for the fact your pedal when in the 6 o'clock position is higher than it was before.
Click to expand...
This is backwards logic, short cranks are also lower at their 12 o'clock position. My short cranks on my BBS-02 let me run my seat lower, and my knees are happier.
 
Nah, your butt will have a higher CoG.. you can argue with physics, but you won't win.
If you are riding in said position then you are probably going fast and CoG will come into play any time we aren't going in a straight line.

Going from a 175mm crank to a 152mm crank is very close to an an inch difference so an inch higher seat does matter.

I'm curious about any aerodynamic improvements you'd get from the modification alone. The effect you're talking about can be had by adjusting the handlebars without negatively affecting CoG.
 
While doing my first conversion I couldn't remove crank. As result e-bike was operating by throttle only for few few weeks while I was waiting for different PAS. It was OKish, but I very much prefer PAS. Using thumb throttle all the time is just uncomfortable. Second and third e-bike are without throttle and with torque sensors. I don't really understand people who don't pedal.
 
ebike4healthandfitness said:
Read about the hour record in post #31.

Some more information gained by wind tunnel testing:

speedandcomfort.com

Crank Length

How Low is Too Low? This was one of the first reasons that we explored the shorter cranks. While developing faster rider positions in the wind tunnel, it was quickly apparent that many riders needed to get lower in the front but simply couldn’t because of upper thigh / stomach interference...
speedandcomfort.com

View attachment 362844
Click to expand...

I've read all 3 links now and don't see any quantification of the aero increase.

This is all in the context of time trial bikes, which nobody here is using.

This seems dubious so far as to applicability to ebikes.
 
None of them provided numbers or graphs talking about it. Let me know i speed read too fast and what i'm missing.
What i powerskimmed looked like the usual assertions without evidence we get in bike industry articles.
 
bengxe said:
My BBS-02 bike's seat is too low,

This is backwards logic, short cranks are also lower at their 12 o'clock position. My short cranks on my BBS-02 let me run my seat lower, and my knees are happier.
Click to expand...

If you switched to shorter cranks and didn't have to raise your saddle that tells me your saddle was too high to begin with. You probably did this because your original cranks were too long.
 
How does the center of mass effect handling? I mean where is the ideal place for the center of mass to be when trying to turn side to side quickly?
 
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Okay, that doesn't make sense. This opens more questions than answers them:

- How does a 7.5 millimeters of higher seat post drop anything by 30mm?
- 3.5% improvement as measured by what and by whom?
- Could we achieve this with different handlebar positioning? if so, the argument is null
- Is this on a road bike with funny geometry and a super skinny rider? ( IE not applicable to an ebike )

I would not use this as proof that raising your seat is more aerodynamic. We need more than that.
 
Okay, are we counter adjusting for seat height or not in this measurement? how was the measurement done, was it in a fixed position where the knee was in a more ideal position, or was it under motion?

I find that going from 175mm cranks to 165mm made pedaling goes from painless to painful. I had to raise my seat by 10mm to counter that. The seat height gain is proportional to the crank length drop.

This would work much better on a bike designed for it.
 
ebike4healthandfitness said:
If you switched to shorter cranks and didn't have to raise your saddle that tells me your saddle was too high to begin with. You probably did this because your original cranks were too long.
Click to expand...
Again, no. My seat is and has always been (much) lower than an ideal pedaling height, because a low cg and ease of getting on and off is more important to me than pedaling efficiency on a bike with a motor. Going from 170 to 152 cranks let me drop the seat even further, because the only thing that matters to me about pedaling is that I can do it without hurting my knees.
A lower seat keeps your thighs more horizontal, reducing their cross sectional area. How much that affects your torso angle depends on how fat you are.
 
Hummina Shadeeba said:
How does the center of mass effect handling? I mean where is the ideal place for the center of mass to be when trying to turn side to side quickly?
Click to expand...
If you're only thinking about turning side to side then your ideal cg height is probably pretty close to an ideal pedaling height, but what if you need to stop quickly, or descend a steep trail?
 
bengxe said:
If you're only thinking about turning side to side then your ideal cg height is probably pretty close to an ideal pedaling height, but what if you need to stop quickly, or descend a steep trail?
Click to expand...
If taking pedaling out of the equation and just trying to do a serpentine course as quickly as possible where would be mass ideally?

The lowest mass would of course be better for accelerating or braking quickly

I remember reading ideal for turning is having the mass centered around what is a central pivot point on the bike .. but I imagine the bike pivots around the center of mass regardless

Ideal I imagine would be having all mass as a single point at the center of this pivot point so less mass needs to be moved, which takes time and effort.

It was a topic here long ago and can’t find it or what the conclusion was.
 
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As in the BBS02 marketing literature:
You can pedal at your own pace while the system operates at the desired speed.
Why not "Ghost Pedal" your mid-drive at the cadence required to operate the sensor while the BAFANG assist operates the chainring at your desired level?

I don't " keep up ", I just pedal at my own pace, if i'm too slow, there's a slight drop out for a second.

"I don’t pedal because chainring is too small and programming wrong on the current Bbs02 I’m using. The programming is too aggressive to keep up with pedalling and also the natural spin speed of the motor isn’t so conducive to actually pedalling. I absolutely prefer to pedal (a lot) but torque sensing makes it much more enjoyable and having the right gear reduction ratio is very important imo"

You don't have to keep up though.

"It'd be clowning w/bbs02b at 30A and the chainring i have on it
(+not willing to give up on speed any more, than i already have)."
 
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