Which Do You Prefer Cadence or Torque Sensor?

[Dave]

Court, I guess this question would be primarily aimed at you, given all of your expierience. However, please. anyone chime in who has knowledge. Do you prefer a cadence sensor or a torque sensor as a means of measuring how much power to give to an electric bike? I know the torque sensor is more expensive, but is it better? Is a cadence sensor used primarily to save on cost, or are there advantages? Thanks all ... still trying to narrow down the choices.

 

[Ravi Kempaiah]

I have ridden both kinds of bikes (Torque Vs Cadence)
There are lots of advantages with Torque sensors. Read more here if you wish to know the details: http://www.electricbike.com/torque-sensors/

Torque sensors "feel" the pressure applied to the chain, irrespective of the bike's condition (stationary or moving) and then allow the electricity to surge from battery to the motor and control the power output continuously.
The cadence sensor can be a bit tricky when you are in situation, let's say, traffic signal somewhere in the middle of a hilly road and now you need to rotate the crankset 2-3 times before the motor starts assisting you, where as the torque sensors feel that the chain is getting tighter and immediately help you.

It becomes very apparent once you ride both kinds of bikes side by side.

 

[Vern]

Ravi, I like your point about getting stuck at a light. I just test rode the Shadow and that happened to me a couple of times. I was in a high gear, stopped at a light, and it was difficult to get going again when the light turned green. I had to do two to three pedals, in the high gear, to get going before the motor kicked in again. The Shadow doesn't have a twist throttle override either. If my commute had lots of traffic lights that would be a deal breaker!! I leave early enough where I don't have that situation too often, but my way home is more tricky.

 

[Dave]

Very good point on the difference in a practical situation. Exactly the kind of information I was hoping would come through.

 

[Admin]

Right on Ravi and Vern! Those are the biggest points right there. Torque sensing is smooth and more immediate. This is especially important in off road, technical riding situations and one of the reasons I really liked the XDURO AMT Pro. The motor is super responsive (bot in switching on and switching off). That bike actually uses a combination of torque sensing and cadence sensing!

If you are commuting a lot and will be stopping at lights, stop signs etc. then cadence can hang you up and require more rotation time to activate. For someone with sensitive knees this is the exact opposite of what you want... and one of the reasons I love bikes with both throttle and cadence sensing, like the Pedego City Commuter. This was one of my early favorites in the world of ebiking and it continues to impress with some great upgrades for 2014.

To be honest, I actually prefer pedelec "cadence sensing" for commuting because you just don't have to push all the time to get the motor going. Basically, you choose an assist level and that's how hard strong the motor will go. It's usually a percentage of full power so like 1 is 25%, 2 is 50% etc. and that powers the bike up to a certain speed and then you can keep pushing harder via the pedals to make the bike go faster and that lets you choose how hard you want to push. With torque sensing, there is a certain level of force you have to apply just to get it to activate (and this force changes from bike to bike).

One of my favorite torque sensing ebikes (in terms of smoothness and force required to activate) is the IZIP Dash. One of my least favorite so far has been the E-Joe One. I'm posting the video below because I may re-shoot this bike... Despite having ridden two demo models, they both had this issue, you can understand that the company wants me to try it again because the experience was just so lackluster.

 

[Dave]

So if I understand what everyone seems to be saying, cadence has advantages but may be at it's best when coupled with a throttle. This seems to be the case because it is not as immediate as torque sensing. Torque, on the other hand, can be more immediate but requires more force by the rider to initiate the motor. The video on the Dash does appear to show the motor kicking in very smoothly. Of course, without actually riding it, tough to tell how much pedeling force is required to start the motor. Very helpful responses, thanks to all.

 

[Ralph]

Hey Dave, You have already read my posts on the Dash, but I just read this thread and was glad to see that Court favors the Dash with its Torque system because I instantly could tell the difference. I put my foot on the pedal and the bike just went.....Seemed like the throttle was not needed. I am glad to know it is a standout performer.

One thing is for sure with each of these bikes, IT IS THE SUM OF THE PARTS that make the bike. I am not sure why the Dash is more responsive with its torque sensor. Court, I think it is because of the combination of the gearless 500watt direct drive hub, the 48v battery and the torque sensing. Is that right? I would love to read your theory on this and the value of the more expensive systems. In broad terms do you get better solutions when you pass a certain price threshold?

 

[Dave]

I was all set to ask you how much of a delay the Dash had, before the motor kicked in. One of my main concerns because I have a lot of busy intersections, with stop signs, where I will be riding. I won't be able to demo the Dash, nearest dealer is 6 hours away here in the Northeast, so posts from you guys are really all I have. Sounds like this Bike is a real winner. If I want the Dash at the pre-order special of $2250, free shipping, I need to make up my mind by 2/14.

 

[Admin]

Hi Ralph! I agree that the Dash hits a sweet spot in terms of performance, and even price. I wouldn't go so far as to say that all "more expensive" ebikes provide this type of experience. For example, the older Stromer Sport that I reviewed in 2012 was not very impressive and it had a lot to do with the build quality and my distraction with the chain. It's true that more money will usually buy more power but if the system isn't responding well or it just doesn't feel right that can be ruined. Standout performers that cost more include the Specialized Turbo, Pedego Interceptor, all of the BH Neo Bikes (even though they have the smaller motor and battery), the Optibike SIMBB system and the Juiced Riders ODK V3.

Hey Dave, funny that the pre-order special ends on Valentine's day... I guess Currie and IZIP are making us choose between their lovely ebikes and our sweet significant others I'd say that the torque sensing does kick in right away and works well. Be careful in fact, at stop lights because if you're putting one foot down and resting the other on the pedal and then you let go of your breaks, the motor can start to kick in and that's not a natural response that we all grew up with. I've also experienced it when backing some torque sensing ebikes up and using one pedal for stability, instead of going backwards the bike thinks I'm sending torque feedback and tries to push forward. It's not a huge deal and these systems are pretty smart so it may not be an issue with the Dash but it does exemplify how torque sensing works. Many new systems combine torque sensing with cadence.

Regardless of pedal assist, this bike has a twist throttle so you could always rely on that. One thing I'm having trouble remembering here is whether the twist throttle works in tandem with pedal assist of if you have to use the LCD computer to navigate all the way to zero to use it. Unfortunately I think it's the latter case.

 

[Dave]

I think the pre-order special on the Dash is a vendor specific offer. It is through Long Island Electric Bikes. I have not seen it offered on Currie's website.

Court, I think you are correct about the Dash, and the throttle not working in tandem with pedal assist. If the torque sensing is quick to kick in, it should not be a big deal.

 

[Electric Bike Specialists]

I just got our first Stromer Sport in for repair. One cool thing about it (and all Stromers) is that you can adjust the sensitivity of the torque sensor by entering 1004 on the display. From there, you can adjust the sensitivity between 30-100%. Very useful, and I'd say lowering the sensitivity quickly results in more of ST1/Eflow -like ride. Highly recommended for anyone who thought they were too punchy.

 

[Admin]

Wow! That's a sweet tip Chandlee. Would you mind sharing it in the Stromer forum along with any pictures or documentation you've got? I think a lot of people would be interested and this is the first time I've heard about it

 

[Electric Bike Specialists]

Would you mind sharing it in the Stromer forum along with any pictures or documentation you've got?

Done! Here's the new thread about adjusting the Stromer torque sensor.

 

[Electric Bike Specialists]

Actually, I just set mine at 10%. Incredible! It's like a Bionx sensor. Feels like a light breeze is behind me!

 

[Chris Nolte]

I was recently speaking with Rakesh the developer of Falco and he had some interesting insight into the "Torque Sensor or Cadence" question. I have always been an advocate for torque sensors, but Rakesh broke it down pretty simply, in his view torque sensors are generally better for fit riders and cadence for unfit riders, obviously it all depends on the application and controller, his system can actually use both and the torque sensor is adjustable. Generally I lean towards a torque sensor if I have the option though. One reason we are so excited about the Haibike and other Bosch bikes is they use torque, cadence and speed sensors as Court mentioned about the AMT Pro.

 

[Admin]

Hey Chris, your post inspired me to dig deep tonight and post my review for the Falco Hx 500 kit. I shot this back in November at Electric Cyclery in Laguna Beach and enjoyed it quite a bit. Pretty advanced kit, would be happy to hear your thoughts on the review or if you think I missed anything. Seems more expensive and advanced than something like BionX but I love how versatile and sophisticated it is.

 

[MikeMc]

IMHO cadence vs torque, is there is no difference. When I ride a cadence bike like the one I own Ride1up 500 mtb, if I experience resistance at the pedal it is no different than torque resistance. I do, however, need to shift my bike gears and my pas level to acquire resistance. I will take that incumbency with a $2000 dollar discount head over heals

 

[rich c]

IMHO cadence vs torque, is there is no difference. When I ride a cadence bike like the one I own Ride1up 500 mtb, if I experience resistance at the pedal it is no different than torque resistance. I do, however, need to shift my bike gears and my pas level to acquire resistance. I will take that incumbency with a $2000 dollar discount head over heals

At speed, maybe you could say that. But if you are stopped, then start pedaling to make a 180 degree turn, I much prefer the torque sensor. The cadence sensor kicking in just comes on too hard to be safe in my opinion. Not to mention the delay after you stop pedaling. You can get into trouble pretty quickly. Most of the cadence sensor bikes also carry a throttle that can make it safer. You must not ride the single trails with a lot of steep climbs and roots. Stop pedaling a cadence sensor, then have to quick hit it hard to snap around a corner on some roots, and I sure don't want hesitation and then a hard kick from a cadence sensor. I want instant torque and then no boost when I stop pedaling. I feel there is a huge difference.

 

[MikeMc]

At speed, maybe you could say that. But if you are stopped, then start pedaling to make a 180 degree turn, I much prefer the torque sensor. The cadence sensor kicking in just comes on too hard to be safe in my opinion. Not to mention the delay after you stop pedaling. You can get into trouble pretty quickly. Most of the cadence sensor bikes also carry a throttle that can make it safer. You must not ride the single trails with a lot of steep climbs and roots. Stop pedaling a cadence sensor, then have to quick hit it hard to snap around a corner on some roots, and I sure don't want hesitation and then a hard kick from a cadence sensor. I want instant torque and then no boost when I stop pedaling. I feel there is a huge difference.

I'm riding in street mostly. I have thumb throttle for quick boost. 9 levels of assist easily switched through. I rode a Bosch mid torque driven. However it was out of my price range. I guess what I was ultimately looking for was excersise. If I level assist to resistance, then I get my workout. If I'm feeling lazy then I let the motor do the work. I'm quite pleased with my decision. I also feel very safe operating the bike. The choice is suggestive.
Thanks for the reply.

 

[MikeMc]

I'm riding in street mostly. I have thumb throttle for quick boost. 9 levels of assist easily switched through. I rode a Bosch mid torque driven. However it was out of my price range. I guess what I was ultimately looking for was excersise. If I level assist to resistance, then I get my workout. If I'm feeling lazy then I let the motor do the work. I'm quite pleased with my decision. I also feel very safe operating the bike. The choice is suggestive.
Thanks for the reply.

Oh yeah. Forgot to mention boost when stop pedaling. You do have to touch the brake to disengage motor before delay. Not really an issue as you'd have to hit brakes on regular bike. It may be quite different when riding trails. I cant comment on that. I'm not riding trails.