E-bike mid-drive motors hardly outperforms hub motors

[markz]

Dyson vacuums uses a generic off the shelf motor from same place you say.
It is called --------- Marketing

https://www.youtube.com/c/arduinoversusevil2025/search?query=dyson
edit - Just the Youtube channel, search Dyson - https://www.youtube.com/user/arduinoversusevil

Here is an article about Lightning rods Big block mid drive:

https://www.electricbike.com/lightning-rods-big-block/

Interesting that the motor used on the big block kit comes from china with a fan (See text under the second picture of the article)...but lightning rods removes the fan.

A fan should allow an inrunner motor to dissipate even more heat. I wonder if a left hand side drive single speed using that same motor would allow keeping the fan?

 

[ebike4healthandfitness]

Dyson vacuums uses a generic off the shelf motor from same place you say.
It is called --------- Marketing

https://www.youtube.com/c/arduinoversusevil2025/search?query=dyson

Here is an article about Lightning rods Big block mid drive:

https://www.electricbike.com/lightning-rods-big-block/

Interesting that the motor used on the big block kit comes from china with a fan (See text under the second picture of the article)...but lightning rods removes the fan.

A fan should allow an inrunner motor to dissipate even more heat. I wonder if a left hand side drive single speed using that same motor would allow keeping the fan?

That link you gave is broken...but yeah I'm not surprised Lightning Rods would use a generic motor.

Anyway, with that motor coming with a fan I have to wonder how much more potential it has? Folks have been making a big deal about cooling in this thread.....but the way I understand it inrunner + fan would be the ultimate in heat dissipation.

 

[markz]

I'd worry about the noise, if that noise can be lessened with a sinewave foc controller then thats good.

That link you gave is broken...but yeah I'm not surprised Lightning Rods would use a generic motor.

Anyway, with that motor coming with a fan I have to wonder how much more potential it has? Folks have been making a big deal about cooling in this thread.....but the way I understand it inrunner + fan would be the ultimate in heat dissipation.

 

[john61ct]

Since I have no need for speeds over say 25mph

I believe a LR setup in left-side fixie mode geared for no more than that, will handle 400# maybe 500# even in the mountains.

If I wanted faster, then putting the LR right-side through a HD IGH should work, certainly Rohloff maybe Kindernay, but then you worry about exceeding their torque limits.

Maybe an IGH like that geared for human pedalling only, once past 10mph

combined with LR right-side fixie mode only?

 

[scianiac]

Anyway, with that motor coming with a fan I have to wonder how much more potential it has? Folks have been making a big deal about cooling in this thread.....but the way I understand it inrunner + fan would be the ultimate in heat dissipation.

Besides water cooling I think open frame outrunners with fans cool much better. We probably spend more time in high copper losses than iron losses so the heat has to travel from the copper, through some potting (poor conductor), through the laminations (also fairly poor), though some interface to the aluminum shell (which is hopefully a good one) then to the air from the heatsink. An open frame outrunner you can just blast air directly over the coils and as demonstrated by high performance RC outrunners you can get crazy power out of them if you have a prop dumping air through them. Not to mention the risk inrunners face of overheating the basically uncooled magnets.

 

[BalorNG]

Anyway, with that motor coming with a fan I have to wonder how much more potential it has? Folks have been making a big deal about cooling in this thread.....but the way I understand it inrunner + fan would be the ultimate in heat dissipation.

Besides water cooling I think open frame outrunners with fans cool much better. We probably spend more time in high copper losses than iron losses so the heat has to travel from the copper, through some potting (poor conductor), through the laminations (also fairly poor), though some interface to the aluminum shell (which is hopefully a good one) then to the air from the heatsink. An open frame outrunner you can just blast air directly over the coils and as demonstrated by high performance RC outrunners you can get crazy power out of them if you have a prop dumping air through them. Not to mention the risk inrunners face of overheating the basically uncooled magnets.

Yup, open RC outrunner on ebike with dedicated fan (think 40mm server fan) that blasts air though the coils will allow pretty massive heat shedding on a small motor even when slowly crawling steep uphill at max phase amps.
Your efficiency will still suffer of course, but than if hub motor people are willing to 'live' with less than 50% efficiency and kilowatts of heat losses, than having only 300 or so for SAME torque and literally an order of magnitude less weight is pretty damn cool.

 

[Chalo]

Your efficiency will still suffer of course, but than if hub motor people are willing to 'live' with less than 50% efficiency and kilowatts of heat losses, than having only 300 or so for SAME torque and literally an order of magnitude less weight is pretty damn cool.

The size, mass, and mechanical friction of multi-stage ratio reduction necessary to use a toy airplane motor in a bicycle usually negates any such advantages in the motor itself versus a hub motor. It also adds cost, noise, wear, and pinch hazards.

 

[Ianhill]

Ive had varients of chain drives, hubs, peddleless all sorts and my most efficent setup whioe still having usable speed was a hub motor.

Hub motors dont climb is fiction its all about mechanical advatage correct kv and rim size for desired task and away you go.

I used a 350wh battery and got on average 10wh per mile traveling around 14mph and climbing 1000ft over that total 35mile, granted i peddled along but to outpace the lycra brigade on a 45kg bike cargo bike while only topping my power up with 350wh aint bad going, the silence of whooshing about on a single speed no deralier is delightful.

I geared the bike so it felt just a bit to tall to pull off leg power alone and the hub was geared at 20mph on a 10s system 40 battery amps with a mxus 3k so it was well underpowered meaning im carrying more weight but that flywheel effect on the rear wheel helped and cogging i didnt even notice the bike roled so well.

I sold it to a forum member as far as i know its still ploding round london to this day many years later ive never took an innruner past 1000miles blown them up even nannying them.

 

[BalorNG]

Your efficiency will still suffer of course, but than if hub motor people are willing to 'live' with less than 50% efficiency and kilowatts of heat losses, than having only 300 or so for SAME torque and literally an order of magnitude less weight is pretty damn cool.

The size, mass, and mechanical friction of multi-stage ratio reduction necessary to use a toy airplane motor in a bicycle usually negates any such advantages in the motor itself versus a hub motor. It also adds cost, noise, wear, and pinch hazards.

You mistake 'toy airplane' motors (geared inrunners I presume) that are indeed hardly suitable for those purposes with much more robust outrunners like that of a drone motors or now very ubiquitous 'e-board' motors.
cost - 90$ for a very high quality motor that weight 1 kg and capable of up to 4kw, I'm currently using cheap 40$ ones but intend to move up a bit.
Laser cut hardware is cheap and light, and you can learn to design your own in free fusion 360 pretty fast (I did).
I have it easy of course, because my bike is DIY and have long stretches of round tubing I can easily attach to... but this project shows how you can have a very light and very powerful system and quite on the cheap, if you are handy:
https://endless-sphere.com/forums/viewtopic.php?f=6&t=112270

(Or an expencive, but massively powerful system, like I said).

Using FOC and belt reduction makes them if not 'silent', but barely audible over tire/wind noise. I find it completely non-issue.
Wear - maybe for very cheap ones, you'll need to replace the bearings with quality ones pretty fast, that's true, or make a system that supports the shaft (I'm working on that too).

Pinch hazard is nonexistend for a swingarm-mounted middrive, and using a combination of a rear swingarm mounted middrive for efficient high speed cruising and dual-reduction middrive for intermmittent high torque application (where losses due to gearing efficiency are an order of magnitude less compared to copper losses if you try to eke out same amont of torque from a typical hub motor) IS the solution that weight on par with a typical *reduction* hub motor (and much lighter than a direct drive), COSTS on par with one, but costs 1/5 of unsuspended weight, allows for monstrous torques on demand, efficient high speed cruising, useable regen braking and the bike remains 'highly pedalable'.

 

[Jil]

Hi !
For those having tested both, is there a significant advantage to mid-drive compared to hub motors for real offroad riding ?

 

[Bullfrog]

Absolutely.

A mid drive can be geared so that you can run the bike in the efficient rpm range and thereby keep the motor a lot cooler.

Plus gearing a mid drive motor can give you torque multiplication and make it where you can climb much steeper hills.

A DD hub motor capable of doing the same thing would be much heavier, require a LiPo battery to supply enough amperage to get the same torque as a mid drive motor using a Li Ion battery, and it will put way too much weight in the rear if the motor is in the rear wheel and way too much weight in the front if a front mounted motor.

If you want to ride off road, a mid drive is the way to go...a BBSHD is my suggestion.

If you want to ride both off road and on road at speeds up to about 30 mph, a geared hub motor like the GMAC may be your best bet.

If you want to ride on pavement at speeds above 30 mph, a DD is the best bet.

Of course you can you use any type of motor on any terrain but it may over heat, not have enough torque, be too heavy and/or have a bad weight distribution which will affect handling.

And YES, I have all three .

 

[Jil]

Thank you Bullfrog :thumb:

 

[Jil]

Using the Motor Simulator from Grin, here is what I got when comparing the GMAC vs the BBS HD.
The BBS HD, when used at nominal pedaling rpm (75 to 100), has a steady efficiency around 82%.
The GMAC efficiency is excellent for a hub motor, but of course depends on the wheel rpm.
Below 5-6% inclination, the GMAC wins, above the BBS HD is clearly better.
https://ebikes.ca/tools/simulator.html?motor=GMAC10T&batt=B5216_GA&cont=BRL10&wheel=28.5i&hp=100&mass=120&grade=0&autothrot=false&throt=6.0&autothrot_b=true&cont_b=PR&motor_b=MBBSHD&batt_b=B36LiGox10&wheel_b=28.5i&mass_b=120&hp_b=100&throt_b=100&grade_b=0&mid_b=true&tr_b=11&tf_b=32

 

[ferret]

Jil.
At what speed did you run the simulation?
At what gear did you simulate the BBS HD?
I'm guessing that at optimal gear for the speed, the BBS HD might have better efficiency below 5-6% inclination as well.

Avner.

 

[Triketech]

I tried a real life simulator a few years ago with two HPV Scorpion FS 26 trikes over an 18 month period. 3 different Direct Drive Hubs, 2 Geared Hubs and two Mid-drives.

Ride profile makes a huge difference in capability and efficiency even with a mid drive as does powered wheel size. Consider that at 0 RPM no matter how many amps you through at it, the efficiency is zero. Pole switching frequency has a huge impact on efficiency from start up to typically up to about 300-600 Hz.

Superman rides with few stops or frequent speeds below 15 MPH tend to favor Direct Drive. No gear losses and most DD motors reach their sweet spot at 150-250 RPM. Stops and hills that are run at speed below about 80 RPM will consume power more quickly as it falls away from the efficient zone. I do a Superman ride about once a week FWIW.

Hillclimbs are current suckers. Mid Drives shine on steep hills for obvious reasons. Geared Hubs work well with hills but will not be as efficient as a mid drive, but far more efficient than a Direct Drive.

Like to actually pedal and shift gears? Take Mid Drive off the list. No matter the unit, they simply suck when it comes to a rider who wants to ride hard. Derailleurs, IGH's no matter, they all shift like their passing a brick past their anuses with a Mid Drive. While its possible to retain a triple chainring its impractical for anything larger than a 20" drive wheel.

We do a lot of climbing in the foothills, typically about 200 feet per mile. We pedal and shift. Keep in mind that 200 foot rise comes with another 200 feet up and 200 feet down to get there. One stretch is 508 feet rise over 1.2 miles. That's the one that gets us home.

So the point is simulators can provide the power and efficiency capability its the operator who defines the outcomes.

On repetitive identical test runs (with high consistency) here are the results:

BBS02 - 5.6 Watt-Hours/Mile
MAC 10T - Infineon Trap Wave - 7.6 Watt-Hours/Mile
MAC 10T - Phaserunner FOC - 6.5 Watt-Hours/Mile
Bafang G310 - Phaserunner FOC - 7.3 Watt-Hours/Mile
Magic Pie 4 - 10.2 Watt-Hours/Mile
Smart Pie 4 - 11.3 Watt-Hours/Mile
9C Std - Infineon Trap Wave - 12.2 Watt-Hours/Mile

As they say "Your Mileage May Vary" and it gets no more literal than that. Each system has its advantages and disadvantages. Consider what the rider wants and what the rider is willing to give up. Its a selection based on the best compromise.

 

[Jil]

Jil.
At what speed did you run the simulation?
At what gear did you simulate the BBS HD?
I'm guessing that at optimal gear for the speed, the BBS HD might have better efficiency below 5-6% inclination as well.

Concerning the BBS HD, I have just checked what are the best efficiency ratios with this motor, and that's around 82%, above 75 rpm. I have considered a Phaserunner, which is perhaps mislaeanding if the inner controller of the BBS HD has not the same efficiency.
I have also considered that used at the right gear, the efficieny of the BBS HD will remain more or less the same whatever the load.
https://ebikes.ca/tools/simulator.html?mid=true&motor=MBBSHD&gear=1&tr=34&batt=B5216_GA&cont=PR&wheel=28.5i&mass=120&throt=24.885970196677476&autothrot=true&grade=18&tf=30
https://ebikes.ca/tools/simulator.html?mid=true&motor=MBBSHD&gear=1&tr=18&batt=B5216_GA&cont=PR&wheel=28.5i&mass=120&throt=15.036287806978876&autothrot=true&grade=2

Concerning the GMAC, the speed depends on the power and the inclination, with 800 watts at 0% it's 43 kph, with 100 watts at 18% it's... 2.4 kph.
Also, I have considered 100 watts of human power for all runs.

 

[Jil]

On repetitive identical test runs (with high consistency) here are the results:

BBS02 - 5.6 Watt-Hours/Mile
MAC 10T - Infineon Trap Wave - 7.6 Watt-Hours/Mile
MAC 10T - Phaserunner FOC - 6.5 Watt-Hours/Mile
Bafang G310 - Phaserunner FOC - 7.3 Watt-Hours/Mile
Magic Pie 4 - 10.2 Watt-Hours/Mile
Smart Pie 4 - 11.3 Watt-Hours/Mile
9C Std - Infineon Trap Wave - 12.2 Watt-Hours/Mile

Interesting data, thanks :thumb:

 

[john61ct]

Which of these are stonger carrying a big load up a long steep hill

IOW will shed heat the longest, assume a CAv3 will prevent damage

 

[Bullfrog]

Which of these are stonger carrying a big load up a long steep hill

IOW will shed heat the longest, assume a CAv3 will prevent damage

The BBSHD will reject excess heat better than a MAC/GMAC.

Which one will produce more excess heat? It depends on how the BBSHD is geared...assuming all other things are equal.

I think the BBSHD to MAC/GMAC comparison is a little apples to oranges. I wouldn't use a BBSHD for riding on the road because your bike's drivetrain will wear and I wouldn't use a MAC/GMAC off road because you can't change the gearing and it will over heat plus riding over rocks/roots can make the clutch come apart...been there done that with both the over heating and the clutch BUT I like my MAC a lot for riding on pavement at speed below about 30 mph.

Want to go faster than about 30 mph...a Direct Drive Hub motor would be my choice :wink: .

So it all depends on how you are going to use the bike/motor...one isn't better than the other, they are just different .

 

[sleepy_tired]

Which one will produce more excess heat? It depends on how the BBSHD is geared...assuming all other things are equal.

It doesn't matter so much which one produces more heat. The problem is that the heat has no where to go with a geared hub motor. You don't need to have multi-speed transmission to have efficient drive. This has been known by EV designers for almost half a century at this point. Probably longer.

If the cooling issue with the geared hub motors was solved by somebody then something like the MAC motor would easily outperform any mid-drive on the market. That size of motor would be almost ideal for any e-bicycle application.

The ideal e-bike drive is what you see on every EV in existence.. whether it's ships, or cars, or ships, or motorcycles, and that is single speed reduction drive. Automobile manufacturers largely abandoned multi-speed transmissions for EVs in the 1970s and for good reason, with very few exceptions. And they have to deal with producing a 1.5 to 3 ton vehicle that won't overheat in hills in congested traffic, yet will still happily accelerate quickly to 90 mph.

The challenges faced by e-bicycles is absolutely trivial in comparison.

And geared hub motors represent that... a single speed gear reduction. The problem is that the motor is encased in metal box. It has no way to shed heat directly to the atmosphere except through the axle.

The other way to get the proper drive on bicycles is to do dedicated left hand drive. However due to the variances in bicycles and packaging constraints (there just isn't much room) unless you have a frame custom designed to have left hand drive or have access to a machine shop in your garage it just isn't feasible.

Aside from a couple French companies producing dedicated drive ebikes pretty much everybody else in the world is getting it wrong when it comes to mid-drives on bicycles.

So that leaves hub motors for the most of us. Which is a compromise. But it's a very good compromise for pavement/road/path driven bicycles. And with the advent of statorade a efficient DD hub motor can out-climb any geared hub motor.

Multispeed mid-drives are ideal if you want the smallest possible motor so you can have as light of a bicycle as possible. However for that increased torque you give up speed. So you have to be willing to accept crawling slowly up steep hills.

This isn't a problem with e-mtbs, but in traffic it's very unpleasant. For the rest of us DD hub motors will do a better job maintaining speed while climbing. Bigger motor with more power is the solution. There is no way around it.

If we are willing to use a 20 inch wheel then all our problems would be solved, except for the 20 inch wheel issue.

 

[Jil]

Aside from a couple French companies producing dedicated drive ebikes pretty much everybody else in the world is getting it wrong when it comes to mid-drives on bicycles.

Which French companies are you talking about ?

I have myself a GMAC/Phaserunner, and I love this setup. But considering efficiency and overheating, when it comes to very steep hills (8% or more) with standard size of wheels (26" or higher), i.e. typical offroad environment, it's clear that a hub motor, even with an excellent efficiency like the GMAC, cannot compete with a mid-drive motor on the right gear.

GMAC vs BBS02 @10% and 10 kph
https://ebikes.ca/tools/simulator.html?motor=GMAC10T&batt=B5216_GA&cont=PR&wheel=26i&hp=100&mass=120&grade=10&autothrot=false&throt=29.5&autothrot_b=false&cont_b=PR&motor_b=MBBS02&batt_b=B5216_GA&wheel_b=29i&mass_b=120&hp_b=100&throt_b=10.55&grade_b=10&mid_b=true&tr_b=34&tf_b=30&bopen=true&gear_b=1

GMAC vs BBS02 @16% and 7 kph
https://ebikes.ca/tools/simulator.html?motor=GMAC10T&batt=B5216_GA&cont=PR&wheel=26i&hp=100&mass=120&grade=16&autothrot=false&throt=45&autothrot_b=false&cont_b=PR&motor_b=MBBS02&batt_b=B5216_GA&wheel_b=29i&mass_b=120&hp_b=100&throt_b=11.1&grade_b=16&mid_b=true&tr_b=50&tf_b=30&bopen=true&gear_b=1

 

[donn]

But considering efficiency and overheating, when it comes to very steep hills (8% or more) with standard size of wheels (26" or higher), i.e. typical offroad environment, it's clear that a hub motor, even with an excellent efficiency like the GMAC, cannot compete with a mid-drive motor on the right gear.

If the cooling issue with the geared hub motors was solved by somebody then something like the MAC motor would easily outperform any mid-drive on the market.

Sounds like you're more or less on the same page there. That leaves the sleepy_tired's direct drive hub. I sure like mine! But I think we should add, not only is this a relatively heavy motor, it needs a fair amount of power to realize its potential, doesn't it? I feel fairly comfortable with a nominal 1500W setup, but in more challenging terrain one might want more.

I mean, checking it out on the simulator, I see that a 9C with Statorade can walk up that 18% grade in "never" condition with 239W, but at 31% efficiency, the rider's 100W is doing most of the work. I mention this regarding nominal power limits in Europe.

 

[BalorNG]

But considering efficiency and overheating, when it comes to very steep hills (8% or more) with standard size of wheels (26" or higher), i.e. typical offroad environment, it's clear that a hub motor, even with an excellent efficiency like the GMAC, cannot compete with a mid-drive motor on the right gear.

If the cooling issue with the geared hub motors was solved by somebody then something like the MAC motor would easily outperform any mid-drive on the market.

Sounds like you're more or less on the same page there. That leaves the sleepy_tired's direct drive hub. I sure like mine! But I think we should add, not only is this a relatively heavy motor, it needs a fair amount of power to realize its potential, doesn't it? I feel fairly comfortable with a nominal 1500W setup, but in more challenging terrain one might want more.

I mean, checking it out on the simulator, I see that a 9C with Statorade can walk up that 18% grade in "never" condition with 239W, but at 31% efficiency, the rider's 100W is doing most of the work. I mention this regarding nominal power limits in Europe.

18% is really steep so far as ON-road is concerned, I've met similar slopes only once in my ride around our (to be fair, pretty flat) part of Central Russia. Even walking up and and pushing the bike was a considerable effort, almost like climbing stairs!

But than, if you weight not 150, but 250lbs and you bike is on hefty side as well - ability to have huge torque on demand becomes not a luxury, but a requirement.

 

[sleepy_tired]

Which French companies are you talking about ?

LMX is one. Started off in endless-sphere forums, I believe.

There is a second one that has a left hand belt drive that I saw in a video, but I can't find it right now.

, i.e. typical offroad environment, it's clear that a hub motor, even with an excellent efficiency like the GMAC, cannot compete with a mid-drive motor on the right gear.

Well yes. That is what I said in my previous post. Slowly crawling up hill isn't a problem with e-MTB. If you have to go 10-15 kph on a street around other traffic then that is much more of a issue.

Also your graph is goofy. It should be more like this:

https://ebikes.ca/tools/simulator.html?motor=GMAC10T&batt=B5216_GA&cont=PR&wheel=26i&hp=300&mass=120&grade=16&autothrot=false&throt=100&autothrot_b=false&cont_b=PR&motor_b=MBBSHD&batt_b=B5216_GA&wheel_b=29i&mass_b=120&hp_b=300&throt_b=11.1&grade_b=16&mid_b=true&tr_b=50&tf_b=42&bopen=true&gear_b=1

The smallest front cog you can fit on a BBS** motor is 42 tooth. At least what I am aware of. Plus people are not going to run at 11% throttle. And they are going to be putting a lot of effort into pedaling. More then a 100 watts in most cases.

Of course the Mac motor still overheats after a few minutes and that is what I expect to happen. But it still will get you up 1-2 km before it does.

...

Anyways my contention is that you can design a single-speed motor to deal with these slopes.

Geared hub motors won't do as they are motors in a box and there is no direct cooling, so mentioning it was a bit of unfortunate red herring on my part. I was saying IF the cooling issue was addressed a motor of that size could work very well and be packaged very well to fit a typical bicycle. But that is a big IF and I don't see the cooling problem being solving any time soon.

Here is a very crude fantasy motor example to explain what I am talking about:

https://ebikes.ca/tools/simulator.html?motor=MSAW2013+SA&batt=B5211_PF&axis=mph&mid=true&tf=30&gear=7&kv=55&cont=PR&grade=16&cont_b=PR&motor_b=MSAW2013+SA&batt_b=B5211_PF&tf_b=30&mid_b=true&gear_b=7&grade_b=0&kv_b=55&bopen=true

It is a imaginary Crystlyte SAW 20 motor (small 3.4kg dd motor) that was re-wound for a 55 Kv that is injected with statorade to improve cooling. I don't know if that is possible to have that winding with that motor, but for the sake of argument lets pretend it is. The gear ratio is 7:1, which is actually something very reasonably obtained with a single stage 219 metric chain drive. Now this is a SPM outrunner motor.

If you fiddle around with the settings, such as using a imaginary controller with 100 amp limit and reduce the gear ratio you can get even better results. This style of setup loves amps, apparently.


And note that there actually exists motors like this, at least as far as I can tell:

https://store.tmotor.com/category.php?id=7

Those are big efficient outrunner SPM motors. I haven't figured out how to do all the math yet to figure out how feasible this all is, but on the surface it seems like it will work. They have Kv ratings down to the point were single stage reduction is possible.


Now a inrunner IPM motor with first stage planetary reduction drive in addition to a similarly sized chain reduction drive would be a lot lighter and a lot smaler. With a proper FOC controller that can do field weakening you can have a extremely massive usable RPM range. This means we can take advantage of this by providing extremely low gearing while still being able to reach good top speeds.

Like what you see with the CYC X1 Pro motors/gearbox setup. (although it is a outrunner SPM motor, it is very fast) I think that a huge potential for those motors is wasted by trying to tie it to the bicycle crank and there is no benefit to having multiple gears with these motors. If it was possible to turn the motor and gearbox around so it was reversed and then tie it to a 11 to 70 to 100 tooth rear sprocket with 219 chain then you would have a e-bike that is essentially unstoppable as far as slopes are concerned. Unfortunately you can't reverse the gearbox as it has a integrated clutch.

So this is still fantasy stuff. Like I said in my other post it's not really all that useful approach for 90% of us unless somebody produces custom frame around this sort of setup. Which I see as extremely unlikely unless you just go out and buy something like the LMX.

 

[Bigwheel]

The thing that is most important to me as a long time cyclist that also has been messing with assist for over 20yrs, both e and ICE although none of that for quite awhile as it was just a placebo I used until battery tech became better, is how I interact at the pedals with the assist while achieving my goals of speed over ground being roughly twice as fast while climbing or against headwinds as I would be if I didn't have assist. I am happy to put in my part and like the feel of that effort but I have found that being able to ride at the edge of my "sweat" zone, sorry no HR monitors or such used, is just how I find myself at my happiest during and after a ride.

In order to get there I use both hub, Grin All Axle DD for my primarily any type of road and some trail drop bar bike, and a TSDZ2 on a FS short travel bike. The former is throttle only and the latter torque assist. I landed on this combo in my mind long ago and the hub motor bike type was my first try after I got a decent battery to go along with it. In my mind the front drive aspect was just to intriguing to ignore as well as the option to swap easily into a regular wheel, which admittedly I have never done.....The one thing I made sure of was that I had the gearing to be able to pedal effectively at speed and while climbing which I got using a Schlumpf Speed Drive crank and a cassette/derailleur. Up until that point I had ridden a very early Bosch bike enough to know that PAS had promise but was happy enough just using a throttle with cruise to dial in assist and have my own way with the cranks as I had been doing for years with my various ICE experiments.

I have gained alot of elevation on that setup over the years and other than relying on the motor too much on a very hot day on a very steep hill after a long day at work and frying my controller never have experienced anything other than my original concept of being able to double my speed efficiently enough to warrant the extra weight on board. After some high speed, high consumption runs of 30mph/30wh/mi just to see I settled down to averaging in the low 20's and mid teen wh/mi consumption rate. Got my exercise ya ya's in and got to know my neighborhood within a 30 mile radius quite well.

Having been primarily a mtb guy for a long time when I got to try a TSDZ2 bike and felt the torque assist was at least similar to the Bosch I had ridden I got one and set it up on my hardtail at first. Immediately I could tell that it was a much better fit for single track riding pedal feel wise at the lower cadence associated with that and also got along the road to the trail well enough also.

But the bottom line is that while one can cross over onto the other what I have found over time is that one is preferable to the other for rides that predominate in one form or another and having both tools in the shed is a wonderful thing! Sorry for the ramble, it's a crappy day here and I'm bored.....