adlai

So I have a mid drive electric bike and while it works for hills, imo it actually is roughly the same for hill climb as an older hub motor system that I own.

The issue is that for some hills that are so steep that I have to pedal constantly to keep on moving. Once I stop pedaling, I stop moving. I cant ever build up enough momentum even on a mid drive ebike to be able to coast even briefly. The constant pedaling is of course noticable and tiresome.

​​​Is there any system that would do better here than a torque sensing mid drive? It does make the hills easier than an analogue bike which I would either end up walking or exerting serious effort. But the hills still are noticable in effort.

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308jerry

I don't have much for hills in my area but my Juiced Ripcurrent has cruise control and a throttle. Guess I'm going to try it out on a hill to see exactly how it works..

cat0020

Hill on pavement?
hill on trails?
muddy or deep rutted hill?
Gotta be more specific than just "hills"

Pop N Wood

Not really sure I'm following you. If the pedals stop turning the pedal assist cuts off motor power. Seems like that should happen on any bike without a throttle.

If I set the assist level high enough the bike will power up any hill I've encountered. I do need to at least ghost pedal to keep the controller sending juice to the motor. It is common for me to stop pedaling and use the throttle to crest the very top of a hill.

So is it the fact you lose power when you stop pedaling or the idea your motor doesn't have enough oomph to keep you moving that you are worried about?

2old

As above, whether you have a torque sensor or cadence, if you stop pedaling on an ascent, you stop. The only solution is to have a throttle handy, and if the hill is so steep that you still stop or go too slow, you need a bigger motor. Best bet is a powerful mid like BBSHD which you should be able to ascend almost any hill in max assist and lowest gear with its throttle or a super powerful (and heavy) hub.

roadcrankr

I am unaware of a mid-drive system allowing a throttle.
Thought it only applies to hub-drive units.

308jerry

Not saying they all do, Bafang has a throttle on their mid drive system..

Chuck Naill

I find hills going down makes them easier.

adlai

Eh, best bet might also be hacking the ebike to accept a throttle

2old

Many (most) DYI kits have a throttle. Big OEM's (Specialized, Trek, Giant) don't because it removes them from Class 1.

adlai

entertaining video. This is the hill climb I have in mind. 15-20mph up fairly steep hills like so.

Pop N Wood

My BBSHD will easily sustain 30+ mph up a hill like that with me pedaling. The thumb throttle is limited to something like 80% of max assist, you will actually get more boost by pedaling rather than throttle only, plus whatever power your legs contribute.

Smaug1

Exactly. The mid drive system would be able to give more torque, as it uses the bikes chain/sprocket gear system to further gear down the motor. The downside is that the big brands don't have throttle, so if you're going up a hill and you stop pedaling, power stops too. If you have this type of mid drive, your best bet is to put the assist at max and just pedal lightly, just shy of ghost pedaling, to keep the power coming.

Your hub drive bike, assuming it has throttle, can keep power on when you stop pedaling, so even though it doesn't benefit from the low bike gear as a mid drive, it can keep power on even when you quit pedaling.

I think you should just stick with your mid drive and pedal lightly the whole time. Full power on those things is a LOT of boost; you shouldn't have to pedal at a "bothersome" level to climb hills.

Pop N Wood

Why do you keep talking like mid drives don't have throttles? All of Bafang's mid drive kits can accept a throttle. They make more ebike motors than anyone.

IMO stay way from the European spec bikes. They are the one that make throttles outlaws.

Smaug1

Sorry, it's just that the mid drives that I see are all Bosch in the LBS.

Pop N Wood

I hear you. Seems like many factory bikes don't have throttles. Probably a combo of European regulations and warranty issues.

Bosch seems almost like Apple in their proprietary approach to their products. Not sure if they are trying to protect their image or if they just want to milk the consumer.

The Chinese brands don't seem to give a hoot. Let people hotrod

2old

AFAICT, all of the "big's" (Bosch, Shimano, Brose, Yamaha, etc) mid-drives are proprietary.

Smaug1

Bosch/Trek are probably just thinking about regulations and liability, when people eventually misuse their bikes. I guess that would fall under "protect their image". There is real value in the Trek brand name and they have some cachet with the Bosch motor brand too. It's quality stuff, and that lets them charge more. (actually, DEMANDS that they charge more)

The Chinese brands don't give a hoot because they are literally fly-by-night. If they get sued, the close the business, move down the block and start again with the same tooling & staff, but new company name.

Pop N Wood

Bafang is the world's largest ebike supplier. Can't speak for the other brands, Chinese or otherwise, but Bafang makes some super high-quality stuff. I know the one I've been flogging hard for a few years now is most excellent. Hardly fly by night.

I have read that some of their newer stuff that is getting popular with bike manufacturers is heading more into the proprietary lock out paradigm. But the DIY stuff is still primarily open source. A good thing IMO

Smaug1

I wasn't referring to Bafang, but the bike manufacturers who BUY Bafang.

I've heard Bafang makes good stuff and I believe it. What the OEMs do with their product is not really their worry.

Example: My first eBike was a heybike Ranger, with 500 W Bafang hub motor. It was advertised as a Class 3 eBike, but set up as a Class 2 from the box. Going into software was easy to unlock throttle up to 25 mph. (takes it out of Class 3 and into moped territory, except that the bike didn't have a plate frame or DOT lighting.) Questionable but legal, since the bike was delivered as Class 2.

Trek and others who use Bosch motors set up their bikes as Class 1 (Active Line) or Class 3 (Performance Line). I'm not even sure Bosch motors have a provision for throttle.

Pop N Wood

Good points.

As for legalities, I'm not sure how ebike laws can be enforced. All these bikes and kits are software limited. How can a court let a lone a cop on the side of the trail prove that one way or the other?

I really like the fact I can adjust the assist levels as well as the soft start application of power. Bike is really smooth.

Calsun

A Class III bike will allow for pedal assist at higher speeds - up to 28 mph. I bought a Specialized Turbo Creo because it would provide pedal assist at higher speeds and allow me to gain momentum and use that momentum on hills. The Specialized bike provides power assist that will drop off gradually at faster speedsl. Other bikes would have programming for a hard cut-off of power at 18 mph and that would actually kick in at 15-16 mph and feel like the brakes were being applied.

At the time I also tried the Trek Domain+ but the bike was 10 lbs heavier and not as nimble as the Specialized Creo and the power cut-off was not nearly as smooth. That was in 2021 so current Trek bikes likely have improved. The Nm torque from the motor is also important but less so for a Class III bike where the rider is going to contribute a lot of the power for propelling the bike.