hill climbing? 750W hub versus 250W mid drive

[tgianco]

Well, I know what is "supposed" to be, but my old 750w hub drive Himiway Cruiser flew up steep hills while my new mid-drive Himiway A7 Pro struggles... let me amend that, I am struggling with it. Maybe I AM a lazier rider than I thought I was.

 

[m@Robertson]

This is one of those arguments where people jump through hoops to cheer for their favorite team. But real money is being spent by the person asking the question, so its important they get an answer that doesn't knowingly encourage a waste of money by trusting a bad source.

Here is an objective test of 14 hub motor'd ebikes. I have it tee'd up past the initial intro speech to launch straight into the test description and the tests themselves. Just watch. You will see how hub motors behave in hill country. You should get an idea real fast as to whether this is what you want out of an ebike. I would stick with it for all 14 tests because it shows you runs with big wheels, small ones that do give a torque advantage, big watts etc. Its also worth noting that the measure of grunt (torque) is "continuous" amp output on the controller, and you can't guarantee what a given factory bike has inside. So a 1000w motor with 20" wheels and a 52v battery could be saddled with a 15a controller and you are ... well, screwed.

Note these are geared hub motors, and direct drive hubs have less torque, until you supersize them with something like a QS203 v3 pump like 3000w+ thru it.

 

[Chargeride]

I climb my geared 750w hub to pretty well its limit off-road up mountains and run it at 2kw, this requires short fast bursts of around 30 seconds before it overheats, but it does cover a lot of ground during that.
The same track, my stock bbshd just tootles up in the same time, is far more controllable as I'm not desperately trying to keep the speed going, not the slightest bit of overheating and uses less battery doing it.
I can also run full size wheels with a larger contact area.
The bit starting at 5.40 in this video would be impossible on a hub, you need crawler gear control.
TBh, I couldn't possibly imagine taking my hub up there, the effort reqd to keep it spinning is beyond me.

 

[Stefan Mikes]

I climb my geared 750w hub to pretty well its limit off-road up mountains and run it at 2kw, this requires short fast bursts of around 30 seconds before it overheats, but it does cover a lot of ground during that.
The same track, my stock bbshd just tootles up in the same time, is far more controllable as I'm not desperately trying to keep the speed going, not the slightest bit of overheating and uses less battery doing it.
I can also run full size wheels with a larger contact area.
The bit starting at 5.40 in this video would be impossible on a hub, you need crawler gear control.
TBh, I couldn't possibly imagine taking my hub up there, the effort reqd to keep it spinning is beyond me.

Lovely!

Charge, how about climbing Mt. Snowdon from Llanberis in the cold season? As I can understand, cycling is banned in the warm season there. Would the trip be doable in some late Autumn or early Spring?

 

[Chargeride]

Yes, it's quite popular, but most people carry their bikes up, even electric versions, I have a plan to take a mad creation up there.
You can ride all year round, but there are strict time constraints in the popular seasons, but this being Britain, you just constantly apologise if riding out of hours.
Embn took a 300 quid hub drive supermarket bike up there.

 

[m@Robertson]

He calls these the most powerful 14 for under $2000. Is it coincidence that each of them agreed to pay him a kickback on sales?

None of that matters, though. Objectively you can just sit and watch how a hub motor'd bike operates on a steady, fairly steep hill. And if you stick with the video long enough you can see the same story repeat itself 14 times. If thats what someone wants in a hill-climbing ebike then by all means go buy one.

Some don't even have adjustable saddle heights.

Irrelevant. Saddle height affects pedaling which is not a part of the test of the bike's ability, on its own. Thats why using the same hill every time, and flat out throttle-only, is so important. Pedaling and muscle introduces variables that ruin the test of the bike.

In a little box on a bike, I can carry the stuff I need to measure a grade in a couple of minutes, but he didn't measure the grade. None or all those bikes could be adequate for Rexlion.

This too seems irrelevant. The point is you are seeing how a singlespeed motor handles a steady grade (over and over again).

Anyway, the test used throttle only, but Rexlion asked about PAS.

He sure did, and he said

I enjoy bicycling, but if I wanted to work my tail off during the climbs I'd just ride an acoustic!

Which seems very clear.

By "steep," Rexlion means he'd rather use PAS than tire himself out.

No. PAS does not give more assist than full throttle, and if someone wants more than what you see in the video, they will have to work their tail off. Simple.

@Chargeride posted an intelligent, experience-based post above on one versus the other. With more video.

But for the people who just want to learn a straight answer, and could care less about the cheerleading and typical internet arguments over alternative facts... tune out the argument and just watch the video. You can believe your eyes.

 

[m@Robertson]

14 bikes go up hill. See and hear obvious results. Use brain. Decide. The end.

 

[Rexlion]

I would be pedaling with PAS, not using the throttle. I don't mind working along with the motor, I just don't want to work hard enough to make my legs feel like jelly.

I've been thinking about a trip to Acadia NP and in my imagination I could picture myself pedaling to the top of Cadillac Mountain. But who am I kidding. Probably my legs would feel like jelly no matter what ebike I rode up that slope. Maybe if I were 35, and not 65.

 

[Rexlion]

That's an interesting situation with the ball bearing. Hmm.

 

[m@Robertson]

Test both hub and mid-drive systems to see which feels better for climbing.

exactly this!

I would be pedaling with PAS, not using the throttle. I don't mind working along with the motor, I just don't want to work hard enough to make my legs feel like jelly.

It *should* be possible to put the mid on the highest PAS which will in turn make the climb easy. That will also eat more battery so the decision on-bike if its the right one for the job be centered around dialing back the assist to the point where you have the option to get the effort output you choose to exert, and not drain the bejesus out of the battery doing it.

I try and set the gear for pedaling to be one more gear lower (bigger cog) than I would normally use without assist. Then sit there without shifting up the hill and adjust my PAS setting a click up or down as the slope lessens or increases from one city block up the hill to the next. Going one gear lower means I never bog the bike down and can always keep pedaling. I use the PAS output instead of the derailleur to deal with the changing hill slope. I go a bit faster or slower as a result but my cadence and effort stay pretty much the same which is what I want. This is a city street so on an mtb on singletrack a gear sensor and shifting would probably be smarter.

 

[AvalancheRun]

I had a Haul ST (1000 watt Bafang restricted to 750 watt / 90 nm torque), and have a Bosch Performance Line with 75 nm torque.

750 watt - will do a lot more work for you

250 watt Bosch - will feel seamless, like you're a professional cyclist crushing hills

 

[Rexlion]

Test both hub and mid-drive systems to see which feels better for climbing.

Exactly the thing to do, yep! This morning I did exactly that.

The problem is, the ebike shops are pretty limiting about where a person can ride to try out their ebikes. One stays close to the shop. And they are all located in flat areas. So I started watching the FB listings. Someone in the city listed a Tenways Ago T for sale. 250W Bafang mid drive, Gates belt, Enviolo hub. Beautiful dark green bike. I thought I'd love it, so I arranged to give it a test ride. The fellow lives in a neighborhood with nice big rolling hills, some are probably 15 degree grades. A great place to find out how the mid drives feel on the hills.

Well, I wasn't impressed. Even on top PAS 5 the ebike felt underpowered in comparison to my R1Up LMTD with 750W rear hub. So this afternoon I took my LMTD out there and ran the same hills, and the LMTD is definitely more energetic. The steepest hill in the neighborhood forced me down to about 8 mph on the Tenways in max PAS, but I topped that hill at 17 mph in max PAS with the R1Up and my legs felt better at the top (probably due in large part to climbing the hill twice as fast, so the legs didn't have time to feel the burn so much).

I also found the Enviolo's shifter to be counter-intuitive. My mind wants to think that I should rotate the control upward to go faster, when it's the opposite: rotating upward downshifts for hill climbing and going slower. I kept doing the opposite.

I liked the fact that I would gain built-in front and rear lights and also fenders, all of which my LMTD lacks. But the lights on the Tenways were of inconsequential brightness IMO. And there was no end cap on the grip that I could remove to attach my usual mirror. Brakes were satisfactory but not as good as on my R1Up. I declined to buy the Tenways even though it was at a really low asking price.

I did, however, really like the saddle on the Tenways! A Selle Royal Essenza. I've now ordered one to replace my current Cloud 9.

All in all, this experiment led me to conclude that torque numbers don't lie. A higher torque hub motor can trounce a lower torque mid drive motor, given similar leg vigor on each... on a short sprint, anyway.

 

[Stefan Mikes]

Try some mid-drive motor different from Bafang on a good e-bike
We know what the peak power is on a good brand mid-drive motor. A good e-bike will also have a proper gearing.

Note: With any mid-drive motor e-bike, you need to be in a gear as low as to maintain a proper cadence of >70. If you expect a mid-drive e-bike would just lift you uphill with a lazy pedalling then it is not going to happen

 

[Rexlion]

Try some mid-drive motor different from Bafang on a good e-bike
We know what the peak power is on a good brand mid-drive motor. A good e-bike will also have a proper gearing.

Note: With any mid-drive motor e-bike, you need to be in a gear as low as to maintain a proper cadence of >70. If you expect a mid-drive e-bike would just lift you uphill with a lazy pedalling then it is not going to happen

I agree, and I don't "lazy pedal" either.

 

[Chargeride]

I appreciate this is a bit crackers, but it's a good example of the issue with hubs, you need enough power to pull them into their efficient working speed.

This is very steep and hardly a typical ride, modern turbo mode mid drives can beat this bike in 750w mode at this level, it takes 2000w to get ahead.
But yes, this is an extreme example.

 

[Rexlion]

Your other bike will take you up a grassy 15% slope at 17 mph, and you seemed dissatisfied in your first post. I don’t know why.

I think you've read an assumption into what I wrote. You might want to read my initial post again, because I never stated dissatisfaction with the climbing ability of my current ebike; I only asked how a mid drive would compare because if I buy a mid drive I don't want less climbing ability than what I now have, if anything I'd like more. I had visions of pedaling up Mount Cadillac in Acadia NP rather than driving (but now I've pretty much abandoned that thought), if I take a vacation there this summer.

I'd forgotten the exact number for my Ride1Up LMTD hub motor so I looked it up again... it's 100nm torque. So maybe a BBSHD would be the huckleberry?

 

[Rexlion]

You said if you wanted to work your butt off on hills, you'd ride an acoustic. Weren't you wondering if the Ago T would take you up hills more easily than your current bike? Yes. Otherwise, why would you want it? There are several considerations.

You asked which would pedal up a hill more easily, but you pedaled as hard as possible to compare the bikes. It seems your question was not what would take you up a hill more easily but what would go faster. I often climb at 8 mph, rather than work my butt off or depend on PAS.

Well. Sorry for the misunderstanding. So I'll try to be as thorough as possible in laying out the situation. Of course I pedaled both as hard as possible for comparison. And the R1Up was easier on the legs because I reached the top of the hill in less than half the time. Do I have to also mention that I additionally tried the hill with my R1Up at a slower speed and lower gear, which of course was easier on the legs, too? Because obviously, pedaling at slower speeds and lower gears is easier than pedaling at higher speeds and in higher gears. I didn't think I needed to spell that out. Instead I tried to give the apples-to-apples comparison as best I could.

With the Tenways on that biggest hill, I has shifted into the lowest gear setting on the Enviolo and I still needed plenty of leg push to slowly chug up that incline. Using roughly the same leg force with the LMTD, I only had to drop as low as 5th gear. And pedal that hard for about half the time duration. But 2nd gear worked fine also, with less vigorous leg input.

You made it sound as if I were dissatisfied with the power provided by my current ebike. I'm not really dissatisfied in that way. But there are other factors. I knew that a hub motor would never make it up a climb as long as the one I'd been contemplating (the motor would most likely overheat partway up Mount Cadillac). Additionally, I miss the 'flat foot', crank-forward design of my acoustic Trek Pure Sport and have been thinking that maybe a mid-drive Bosch on an Electra Townie (like an 8d or 8i) might suit me better. But after trying the Tenways, I am inclined to think that the measly 40nm of the Bosch Active Line motor would feel entirely unsatisfactory... unless, maybe if Bosch has some magic pixie dust in their mid drives that makes them seem more powerful than a 80nm Bafang. To my mind, buying an ebike that is less assistant in hill-climbing than what I now have would seem like a step backward.

Now you might be wondering: why didn't this guy explain all of that to begin with?
The answer is: I know better than to introduce extraneous information which might cause people to veer off-topic rather than address the specific question I posed. I've seen it happen all the time on forums. A person asks X and explains that he's thinking about buying Y; the next four responders argue the merits of Y and never address X!

 

[Chargeride]

That only applies to mid drives that can utilise the low freewheel gears.
A normal hub motor being dragged down to low rpm will start turning battery power into heat.

You can of course spend a lot of money on fancy versions designed to operate like that.

There is a sweet spot incline for my hub motor that beats even powerful midrives, running 2000w my hub will destroy a standard road legal midrive, there are plenty of videos though of fit riders on legal MTBs tearing away from powerful 1000w bikes ,I watched a video of that Crusher eFatbike off-road against a legal mtb up a steep difficult off-road path, the legal bike tore away, a combination of fit, skilled rider, using the power and gears effectively.

 

[Rexlion]

, the legal bike tore away, a combination of fit, skilled rider, using the power and gears effectively.

Yeah, I lack the first two! I'm a mediocre sprinter, and incapable on the long haul!

 

[Jeremy McCreary]

Simple questions for anyone who really knows, please:

Q1: In a typical derailleur-based mid-drive, does the chainring turn at the same rate as the pedals, yes or no?

Q2: If no to Q1, does the chainring turn faster or slower than the pedals?

NOT asking about multi-speed MGUs, just typical mid-drive motors. Thanks!