Torque sensor vs Cadence...

[GenXrider]

So all torque based systems are now potentially troublesome since the bafang M600 has crappy programming? FWIW, the bafang m600 isnt a mainstream system like brose/bosch/yamaha/shimano.

Not "all". I said that I've read various posts, but I wouldn't translate that to mean "all" torque based PAS are potentially troublesome because of that one post, when I never said "all" and specifically said that was just ONE example, so you shouldn't conclude anything by that single reference.

Many complain of bad programming for some cadence based PAS systems, so can I use your logic and conclude that all cadence based PAS systems are potentially troublesome?

I never made such a conclusion. I simply pointed out a fact that I had read something repeatedly while giving just one example of many. I never made a jump to making a conclusion that all torque sensor based PAS systems are potentially bad/unnatural.

Why do you think cadence based PAS is better for rural roads? I ride rural roads everyday, what am I missing?

I said that I "didn't prefer" a torque sensor for riding on rural roads. I didn't say cadence is better. I think it's less important when you are just riding along pedaling continuously vs. riding on trails on a mountain bike due to the nature of how torque based PAS functions based on hours of reading from people that have either or both. So, I'm more neutral on the issue in regard to rural riding, and I don't think it's the best value to spend the extra on torque sensor based PAS bikes for that purpose. The feedback I've read indicates the torque based sensor PAS systems seem more touchy and more difficult to get right vs. cadence sensor based PAS.

My preference for now remains to get a cadence sensor based PAS in my first couple e-bikes, which will be primarily ridden on rural roads. For a mountain bike, I see more of an advantage to the mid drive bikes and torque sensor based PAS. I'll cross that bridge when I come to it. I'm sorry if that offends anyone. Maybe I'll change my mind someday when I get first hand experience on different bikes, but I'm just trusting in what I've read from the majority at this point, not any single anecdote.

 

[GenXrider]

I would never argue why you should enjoy what I prefer, it's pretty obvious to most the reason they make both types is because they are both popular. Is one type "best" or better? Oh please....save it for the choir.

Yeah, I've noticed people are touchy on these different topics: cadence vs. torque, hub drive vs. mid drive, fat vs. standard tires, and they take it personally if something is stated that doesn't match up with their beleifs, experiences, or what they already spent their money on.

 

[GenXrider]

I also agree with what was said above - Many bikes can be programmed at their display for a total of 3, 5 or 9 levels of pedal assist. Many ask (I did at first) "why would I want to have to cycle through and choose from 9 different levels?" The answer to me: To have more discrete control of a hub motored bike with cadence sensor.

Yep, that's one of the things I really like about the Ride1UP that I posted the chart for up above, plus being able to modify each assist level to a custom setting is very nice as well. I wish this was more common in e-bikes.

 

[Gongon]

I have just begun the daunting task of researching the different brands, models & technical features available on eBikes. (No small task, lol) My aim is to buy a bike (maybe two,) that has the features, performance, comfort, reliability & customer support that meets my needs. EBR YouTube videos are very helpful.

One aspect I do not see addressed much is torque sensor verses cadence (how hard you are pedaling.) Many of the mid range bikes have only the cadence type sensing which from my understanding, only senses that you are pedaling but not how hard. (So the motor applies the full PAS power whenever you pedal? ...Like a on/off switch?)

On the other hand I understand that bikes fitted with a strain gauge type torque sensor, senses how hard you are actually pedaling & responds with a proportional amount of electrical assist.

I have a friend who owns several eBikes & he says it's all about torque sensing & that a cadence type system is vastly inferior to the torque sensor. Is there actually a big difference in the way the two systems work & more so, is there really a big difference in the way each bike performs?

Anyone with experience riding both types of sensing?... do you feel that one system works better than the other and if so why? Can you explain any advantages or disadvantages to either?

Oh... and for the record, I anticipate doing mostly street riding, paved & gravel roads, along with some lite trail excursions.

Happy riding to All & thanks for your input!

Ride On...
ERD

Hello Mate

I have just installed a Bafang 1000w BBSHD mid mount system (which has cadence PAS) and ridden it 3 times on my local "bike park" trails

My next door neighbour comes with me and has a Giant Fathom e bike with torque sensing PAS.

The Fathom is excellent on the trails with instant power and shut off on demand.

My Bafang system, however, is a very different animal! The power "comes in" after about 1/2 a pedal revolution. When it does, with 1000w, acceleration is quite noticeable depending on the level of power assist.

As I said, I have ridden it 3 times on trails and (and up and down my driveway dozens of times)

I haven't quite got the hang of it yet.

On uphill climbs when I arrive at rocks, I need to anticipate the power needed and usually get it wrong!

If I "go too early" I end up crashing over the rocks.

If I go late, there isn't enough power to get over the rocks.

It may be technique (I have started experimenting with the thumb throttle to give the extra power but it's a bit too abrupt at present).

I am assuming that technique alongside some adjusting of the controller will help.

I won't give up (I used to ride 55 year old trials bikes and they were beasts!)

Also, at the moment, I haven't been able to figure out how to fit the brake sensors so the motor runs on a split second after I stop pedalling - Ok on the road but a nuisance in the bush. (Not sure if that's common to all cadence sensing motors?)

My mates Fathom is much more user friendly with instant power reaction from pedal input.

Not so user friendly at times such as when applying power riding around a tree on sand when the sudden input causes traction loss and subsequently dumping the rider. I've seen this happen with two different riders. again, a question of technique. In those situations my bike would be relying initially on leg power only so less likely to break traction.

Having said that, using the throttle on my Bafang to get moving on an uphill trail is a great help compared with the balancing act getting the Fathom going by pedalling.

I do prefer the Baafang though but that isn't to do with the pedalling, I much prefer the 1000w motor for climbing the trails. The Fathom is limited to 250W in Australia (as it is designed to be used on the roads as well) so I do leave it far behind on those climbs.

I have no desire to use the roads so top speed is more than acceptable at 26 km/hr.

In my case, I was in a hurry to get an e bike, the shops had none due to covid-19 rush and Bafang kit was at Luna Cycles 30 minutes away and I had two mountain bikes to choose from. Rod, the proprietor at Luna was very helpful and I expect his support will be second to none.

Hopefully this is of some help to you - Tom

 

[SLONomad]

I just bought an eAhora AM100 with cadence sensors. At first, I was very disappointed. The motor seemed to have a mind of its own, surging faster when I wanted to go slower. But once I realized I could program it, the problem is much less noticeable. I changed the default from 3 power level settings to 5 and lowered the Level 1 power assist from 56 to 45%. This is especially important when taking sharp turns where you want to have good speed control without braking. After reading the posts above, I may program it to 7 or 9 levels and lower the assist force on Level 1 even further. That said, if you are wanting to do serious mountain trails, I would think you would want the response and control of a torque sensor.

 

[tlippy]

No, I wouldn't say inferior. There's been some negative feedback about some torque based sensor systems. For mountain biking, I would prefer torque sensor based PAS in general, but I'm actually looking to get a cadence sensor based PAS for biking on rural roads for exercise when I maintain a continuous cadence.



No, cadence PAS doesn't necessarily automatically apply full power. Every bike that I'm aware of, even some cheap Walmart ones, have as assist level setting. On some bikes, such as the Ride1UP 500, you can even program the power of each assist level, to control the watts delivered in any particular assist level. When configured for 9 assist levels, it defaults to 25% on PAS 1.

View attachment 59077

Note, it's "pedal", not "peddle". Different meanings.

GenX-have you bought any eBike yet?

 

[ElevenAD]

i have 2 bikes with Torque sensors and one with cadence, i can get a better work out with the torque sensing bikes but i can get close with my cadence bike and when my body is beat to shreds nothing beats my ol cadence bike! would not trade it for the world lol if i could only keep one bike im keeping my Juggernaut HD with its crusty old cadence sensor!

 

[GenXrider]

GenX-have you bought any eBike yet?

I haven't been on here much l lately - it's off season for me. I have not bought one yet because the bike I wanted was not available until summer was coming to an end, so I'm waiting until spring.

 

[JES2020]

I would never argue why you should enjoy what I prefer, it's pretty obvious to most the reason they make both types is because they are both popular. Is one type "best" or better? Oh please....save it for the choir.

I do agree about the software. My hope is that as the e-bike industry matures, folks will get the benefit of some thought placed on that factor at the OEM level. It sure seems a scattered roll of the dice at this point. It's obviously possible to have very nicely done torque and cadence software, as the aftermarket vendors have proven already....

One other point on cadance is that, the number of magnets on the sensor affects the smoothness of aplied power.
Also on my kit the slower I pedal the less power I get, it's not like it's all or none. I really like my cadence 12 magnet system, very smooth and extreamly user adjustable .

 

[JES2020]

I just bought an eAhora AM100 with cadence sensors. At first, I was very disappointed. The motor seemed to have a mind of its own, surging faster when I wanted to go slower. But once I realized I could program it, the problem is much less noticeable. I changed the default from 3 power level settings to 5 and lowered the Level 1 power assist from 56 to 45%. This is especially important when taking sharp turns where you want to have good speed control without braking. After reading the posts above, I may program it to 7 or 9 levels and lower the assist force on Level 1 even further. That said, if you are wanting to do serious mountain trails, I would think you would want the response and control of a torque sensor.

"if you are wanting to do serious mountain trails, I would think you would want the response and control of a torque sensor."
Or a throttle. A throttle gives instant on and off power. I use my throttle to cross busy streets so that I don't have to pedal in top gear and wait for the canance to kick in. (I have programed PAS to kick in after 1/4 turn).

 

[teskow]

The part I don't like about the cadence sensor on my bike is that if you move the crank it powers up. On the torque sensing setting it only powers up if pressure (torque) is applied to the crank so you can move the pedals around to a different, comfortable position while coasting with no power being turned on. Even very light pedaling in torque sensing will not turn any power on which can be nice to maintain a slow speed.

 

[BigNerd]

The part I don't like about the cadence sensor on my bike is that if you move the crank it powers up. On the torque sensing setting it only powers up if pressure (torque) is applied to the crank so you can move the pedals around to a different, comfortable position while coasting with no power being turned on. Even very light pedaling in torque sensing will not turn any power on which can be nice to maintain a slow speed.

I need to check this but if you move the crank backwards, the motor does not engage because I think the sensor is directional (although not sure how).

Can anyone else confirm?

 

[JES2020]

I need to check this but if you move the crank backwards, the motor does not engage because I think the sensor is directional (although not sure how).

Can anyone else confirm?

Confirmed. Also you can set the cadence to short or long delay. And you can set the power level so low you can hardly notice it at low speeds.
This on programmable controllers. But all cads will not power on backwards. ( it's due to the sensor responding to the magnet at position 1 then 2 and not 2 then 1)

 

[AHicks]

The part I don't like about the cadence sensor on my bike is that if you move the crank it powers up. On the torque sensing setting it only powers up if pressure (torque) is applied to the crank so you can move the pedals around to a different, comfortable position while coasting with no power being turned on. Even very light pedaling in torque sensing will not turn any power on which can be nice to maintain a slow speed.

The cadence sensor, on some bikes, has a "sensitivity" adjustment that controls how far the crank needs to be turned before the power turns on. These can be set to be pretty sensitive - which is great for an experienced rider picking your way along a single track, or low speed control in general. A sensitive cadence sensor is NOT going to work out well with a nervous or possibly inexperienced rider. The adjustable sensor on these bikes can be set for 1/4 turn or more of the crank if desired. Bottom line, the cadence sensor counts the number of magnets going by it, and turns the power on when told to. if that count is 1 (not recommended) it's going to be pretty sensitive.

Same deal on a torque sensing bike, only on those you have a sensor that picks up on the wheel's motion. They may also have a cadence sensor! For instance, you don't want the bike to take off on you while at a stop sign waiting for traffic to clear, when you place you foot on a pedal and put some weight on it. Same exact story will be in play to prevent that from happening. Depending on how the bike is equipped, the cadence or MOTION sensor must sense motion prior to the torque sensor being turned on.

Nice thing about MOST throttles on both types, is they can be used to put the bike in motion, satisfying either type system's safety requirements.

Last, if this bike doesn't have a cadence sensitivity adjustment, and you want to "desensitize" the cadence sensor, you may be able to switch to a cadence sensor with fewer magnets. Going from a 12 magnet cadence sensor to a 6 magnet sensor for instance, will "desensitize" the cadence sensor as the crank will have to turn further prior to a magnet passing the sensor.... -Al

 

[JES2020]

The cadence sensor, on some bikes, has a "sensitivity" adjustment that controls how far the crank needs to be turned before the power turns on. These can be set to be pretty sensitive - which is great for an experienced rider picking your way along a single track, or low speed control in general. A sensitive cadence sensor is NOT going to work out well with a nervous or possibly inexperienced rider. The adjustable sensor on these bikes can be set for 1/4 turn or more of the crank if desired. Bottom line, the cadence sensor counts the number of magnets going by it, and turns the power on when told to. if that count is 1 (not recommended) it's going to be pretty sensitive.

Same deal on a torque sensing bike, only on those you have a sensor that picks up on the wheel's motion. They may also have a cadence sensor! For instance, you don't want the bike to take off on you while at a stop sign waiting for traffic to clear, when you place you foot on a pedal and put some weight on it. Same exact story will be in play to prevent that from happening. Depending on how the bike is equipped, the cadence or MOTION sensor must sense motion prior to the torque sensor being turned on.

Nice thing about MOST throttles on both types, is they can be used to put the bike in motion, satisfying either type system's safety requirements.

Last, if this bike doesn't have a cadence sensitivity adjustment, and you want to "desensitize" the cadence sensor, you may be able to switch to a cadence sensor with fewer magnets..

-Al

Going from a 12 magnet cadence sensor to a 6 magnet sensor for instance, will "desensitize" the cadence sensor as the crank will have to turn further prior to a magnet passing the sensor...

The cadence sensor, on some bikes, has a "sensitivity" adjustment that controls how far the crank needs to be turned before the power turns on. These can be set to be pretty sensitive - which is great for an experienced rider picking your way along a single track, or low speed control in general. A sensitive cadence sensor is NOT going to work out well with a nervous or possibly inexperienced rider. The adjustable sensor on these bikes can be set for 1/4 turn or more of the crank if desired. Bottom line, the cadence sensor counts the number of magnets going by it, and turns the power on when told to. if that count is 1 (not recommended) it's going to be pretty sensitive.

Same deal on a torque sensing bike, only on those you have a sensor that picks up on the wheel's motion. They may also have a cadence sensor! For instance, you don't want the bike to take off on you while at a stop sign waiting for traffic to clear, when you place you foot on a pedal and put some weight on it. Same exact story will be in play to prevent that from happening. Depending on how the bike is equipped, the cadence or MOTION sensor must sense motion prior to the torque sensor being turned on.

Nice thing about MOST throttles on both types, is they can be used to put the bike in motion, satisfying either type system's safety requirements.

Last, if this bike doesn't have a cadence sensitivity adjustment, and you want to "desensitize" the cadence sensor, you may be able to switch to a cadence sensor with fewer magnets. Going from a 12 magnet cadence sensor to a 6 magnet sensor for instance, will "desensitize" the cadence sensor as the crank will have to turn further prior to a magnet passing the sensor.... -Al

Nice post Al.
One thing I noticed in my application, going from 8 magnets to 12 solved the problem of a very jerky power band, for the same reason that the sensor has to travel further on the crank to activate the motor.
In my case the 8 magnet ring was not ride able. Adjusting the sensitively helped, but the 12 ring power band is smooth as silk. Just a precaution for the OP.

 

[fooferdoggie]

the torque sensors on the two bikes I had didn't to need caddice or movement. the dap powered bike just resting your foot on the pedal would make you lurch forward if you did not hold the brake lever. my bosch just just need to push hard enough.

 

[JES2020]

the torque sensors on the two bikes I had didn't to need caddice or movement. the dap powered bike just resting your foot on the pedal would make you lurch forward if you did not hold the brake lever. my bosch just just need to push hard enough.

That sounds down right dangerous !
No way to adjust it?

 

[fooferdoggie]

That sounds down right dangerous !
No way to adjust it?

on the dapu? no you just hold the brake lever or don't leave your foot on the pedal. I jerked forward several times a bit of a pain for sure.

 

[JES2020]

on the dapu? no you just hold the brake lever or don't leave your foot on the pedal. I jerked forward several times a bit of a pain for sure.

Wow, remind me not to invest in the dapu , that's a liability issue for sure.
I can imagine a situation, stopped at a busy street inadvertently stepping on the pedal and as you get jerked forward your weight shift put MORE weight on the pedal and...splat !
Is it possible to DC the PAS and use just the throttle?

 

[fooferdoggie]

Wow, remind me not to invest in the dapu , that's a liability issue for sure.
I can imagine a situation, stopped at a busy street inadvertently stepping on the pedal and as you get jerked forward your weight shift put MORE weight on the pedal and...splat !
Is it possible to DC the PAS and use just the throttle?

it has a throttle I jsut tend to rest a foot on the peddle. to many years on a recumbent. but I sold that bike dapu mid drives are not the greatest it ate up the battery really fast.