Singlespeed, hub drive, torque sensor, under 40 lbs?

[Marquezdl]

I have been looking at a lot of ebikes, and I havent found one that is “ just what I am looking for” yet.
here is what I am looking for:
singlespeed configuration
rear hub drive
minimum of 45 nm torque
torque sensor
disc brakes
total weight less than 10 kg (44 lbs)
could be either belt or chain

I am a long time bicyclist now 73 and my legs, knees, and lungs ain’t what they used to be.
I rode fixies for a few years, then switched to singlespeed for about 10 years, then went to IGH. I personally do not like derailleurs.
I live at about 1650 meters (5400“) and the hill up to my place peaks at over 25%.
on my regular bicycle I can just make it up that hill without stopping on a good day. I have a Specialized Turbo Vado and its an AMAZING ebike, but I would be a lot happier with an ebike that is 10-15 kg lighter and more like my old singlespeed DeRosa.
Any suggestions?

 

[m@Robertson]

Put simply, you can't get there from here. A hub motor with a torque sensor is almost a contradiction in terms. They exist but not as far as I know in conjunction with the rest of your feature set.

Maybe a LeMond Prolog, but your Fixie stipulation throws that out.

A Luna Fixed is vey low cost but its not a hub motor, and I can say having owned one that the nylon gears inside the mid drive are not going to tolerate a 25% grade for long. Gates belt and 3-spd IGH so not far off from a fixie.

For that matter any geared hub is going to be totally out of its league on a 25% grade since hub motors are single-speed by their nature. They suck on hills. You'll be 100% of the power going up a grade like that.

The Babymaker is close... and cheap. But its got a cadence sensor.

If I were going that route I would take my Mavic SSC/Vitus 979 out of storage and put a BBS02 on it. Then dial back the BBS02's power to preserve the stays. I'd say you are looking at a DIY project yourself if you are serious about your feature list, but that torque sensor on a hub motor is going to be fun to source.

 

[Marquezdl]

First, I am not looking for an ebike that will go up the hill unassisted. I am looking for a boost. I can make it on my 20 pound bicycle on a good day. A boost of a few nm of torque and I am definitely where I want to be. Working hard but not max effort to get up the steep ramps. For me an ebike is a workout machine as well a a joy to ride and basic transportation.
Second, I have inquired from LeMond about a factory singlespeed prolog. But I havent recieved a reply yet, just an acknowledgement of receipt of my inquiry.
Third, I expect to spend at least $3K.
As far as DIY, thats out For a number of reasons.

 

[Ender]

I'm not sure what the motor torque is but Tenways has several options that were very promising in my searches for lightweight ebikes. I think they're mostly single speed with a belt drive.

The Vanpowers Commuter was another good option for single speed belt drive.

Sorry, no personal experience with either though.

 

[Stefan Mikes]

Marquez, I think you are looking for a unicorn:

• Hub drives are not climbers, especially for the type of hills you are describing (you might easily fry one)
• 45 Nm on a hub drive motor is a laugh in your situation.
• A mid-drive gives you the mechanical gearing advantage where the motor and your legs act together through proper mountain gearing (the ratio of the number of teeth of the chainring divided by the number of teeth of the biggest rear cog shall be less than 1). a hub drive does not provide that advantage
• Again, how would you like to achieve the gearing advantage with a fixie?
• A torque sensor on a hub drive motor is a laugh, as it works on the on-off principle (it detects if you push the pedal, that's it).

The answer for you would be... the latest S-Works Levo SL with the SL 1.2 mid-drive motor (45 Nm) and the top-end drivetrain. The weight is less than 40 lbs, and it is a carbon e-MTB. You are aware of the price, aren't you. Not sure about the availability in your country though.

 

[m@Robertson]

First, I am not looking for an ebike that will go up the hill unassisted. I am looking for a boost. I can make it on my 20 pound bicycle on a good day. A boost of a few nm of torque and I am definitely where I want to be. Working hard but not max effort to get up the steep ramps. For me an ebike is a workout machine as well a a joy to ride and basic transportation.

I get all that. I ride the same way as a lifelong cyclist. I don't think you are understanding the nature of assist on a hub motor. A little 250w geared hub TRYING to providing 45 Nm on even a short 25% grade is going to be so outclassed you are just not going to be seeing any real benefit from it. It is the wrong tool for the job. @Stefan Mikes did a good job of briefly outlining why.

Worth noting: A rating of 45 Nm is not a measure of constant output under all circumstances. If it were, you could argue "I'm getting 45 Nm at all times so whats the big deal I'll take the 45 Nm boost."

 

[Marquezdl]

I dont know about any of that, but what I do know is that I have seen lots of cheap hub drive bikes cruising up the hills where I live. Many times they have groceries on the racks. So I know that hub drives can handle these hills. They are not long climbs, the steep ramps are usually less than 100 meters long, but when you are riding up a 10-12% incline and it suddenly jumps up over 20% for 50 or 75 meters a little boost is very helpful. it looks to me like the local riders are getting very useful boost out of their cheap hub drives. I have no idea how much torque those hub drives are putting out, but Colombia limits all ebikes to a max of 250 watts rated power.
actually, other that the few expensive Specialized mid drive ebikes like mine, virtually all other ebikes I see in Medellin are hub drives.

 

[Stefan Mikes]

all other ebikes I see in Medellin are hub drives

Certainly lightweight ones?

 

[Nordmarken]

Tenways was mentioned earlier and even if it's a bit heavier than what you're after (14 kg something i believe) I can recommend it (have their first model). Single speed, beltway drive makes it maintenance easy. Just wipe it of with a damp cloth.

 

[PSm]

I have been looking at a lot of ebikes, and I havent found one that is “ just what I am looking for” yet.
here is what I am looking for:
singlespeed configuration
rear hub drive
minimum of 45 nm torque
torque sensor
disc brakes
total weight less than 10 kg (44 lbs)
could be either belt or chain

I am a long time bicyclist now 73 and my legs, knees, and lungs ain’t what they used to be.
I rode fixies for a few years, then switched to singlespeed for about 10 years, then went to IGH. I personally do not like derailleurs.
I live at about 1650 meters (5400“) and the hill up to my place peaks at over 25%.
on my regular bicycle I can just make it up that hill without stopping on a good day. I have a Specialized Turbo Vado and its an AMAZING ebike, but I would be a lot happier with an ebike that is 10-15 kg lighter and more like my old singlespeed DeRosa.
Any suggestions?

The 25% grade is a big ask for SS or IGH. With your biking experience and SS history, I would suggest you give the Ride1UP Roadster a Gravel version a try. At $1245, just buy and try, and use their 30 (?) day return policy.

Roadster v2 - Ride1UP | Best Lightweight Electric Bike

A single-speed, lightweight electric bike with a minimalistic stealth design that is agile and capable of reaching speeds of 15mph. Learn more about the best lightweight electric bike.

ride1up.com

I have the road non-Gravel version Roadster, and have over 7000 miles on it, including many metric centuries and some gran fondos. Love it, when I’m not riding my SS analog traditional track-based bike. Doesn’t tick all your boxes, but might be close enough if you can adapt to it. Challenge for anything above 10-12% grade, unless short segments. Hard to know what’s right for you, unless you try.

 

[Marquezdl]

The 25% grade is a big ask for SS or IGH. With your biking experience and SS history, I would suggest you give the Ride1UP Roadster a Gravel version a try. At $1245, just buy and try, and use their 30 (?) day return policy.

Roadster v2 - Ride1UP | Best Lightweight Electric Bike

A single-speed, lightweight electric bike with a minimalistic stealth design that is agile and capable of reaching speeds of 15mph. Learn more about the best lightweight electric bike.

ride1up.com

I have the road non-Gravel version Roadster, and have over 7000 miles on it, including many metric centuries and some gran fondos. Love it, when I’m not riding my SS analog traditional track-based bike. Doesn’t tick all your boxes, but might be close enough if you can adapt to it. Challenge for anything above 10-12% grade, unless short segments. Hard to know what’s right for you, unless you try.

Thanks, but I am not interested in a throttle equipped bike, and my understanding is that all of the roadsters come with a throttle now

 

[PSm]

Thanks, but I am not interested in a throttle equipped bike, and my understanding is that all of the roadsters come with a throttle now

Yeah, my Roadster doesn’t have a throttle.

From what I’ve heard, to make it throttle less, all you’d have to do is buy and plug in this alternate display from Ride1UP

Roadster Display Gen 2 - Ride1Up

This product has a reinforced clamp. When installing, please be sure to tighten the clamp on a straight section of the handlebars and do not tighten on the curved section of the riser bars. Display Manual This is for the Ride1Up Roadster v2 Only.

ride1up.com

 

[tomjasz]

I dont know about any of that, but what I do know is that I have seen lots of cheap hub drive bikes cruising up the hills where I live. Many times they have groceries on the racks. So I know that hub drives can handle these hills. They are not long climbs, the steep ramps are usually less than 100 meters long, but when you are riding up a 10-12% incline and it suddenly jumps up over 20% for 50 or 75 meters a little boost is very helpful. it looks to me like the local riders are getting very useful boost out of their cheap hub drives. I have no idea how much torque those hub drives are putting out, but Colombia limits all ebikes to a max of 250 watts rated power.
actually, other that the few expensive Specialized mid drive ebikes like mine, virtually all other ebikes I see in Medellin are hub drives.

Those of us that have owned both Hub and Mid motors know a hub, geared, or direct drive can be a hill climber. If these naysayers would spend some time on the Grin simulator they'd be surprised.

Hub Motor Advantages 1) Independent propulsion 2) Less stress and wear on drivechain 3) Ability to use internal gear hubs (IGH) 4) Higher peak power capability 5) Potential for regenerative braking 6) Ease of installation 7) Torque sensors options 8) Simpler operation with shifting

Why Hub Motors - Learn

Learn why we chose to keep our focus primarily on hub motor drive systems over mid-drive conversions.

ebikes.ca

 

[JRA]

I dont know about any of that, but what I do know is that I have seen lots of cheap hub drive bikes cruising up the hills where I live. Many times they have groceries on the racks. So I know that hub drives can handle these hills. They are not long climbs, the steep ramps are usually less than 100 meters long, but when you are riding up a 10-12% incline and it suddenly jumps up over 20% for 50 or 75 meters a little boost is very helpful. it looks to me like the local riders are getting very useful boost out of their cheap hub drives. I have no idea how much torque those hub drives are putting out, but Colombia limits all ebikes to a max of 250 watts rated power.
actually, other that the few expensive Specialized mid drive ebikes like mine, virtually all other ebikes I see in Medellin are hub drives.

Could 300 million Chinese eBikers be wrong as well?

Columbia is a country where there must be many bikes that can be converted to suit your needs over sourcing one as above. A Bafang G310 from AliExpress with a 48v system to power it might be an option for you? Upping the voltage won't harm the motor unless overused but for what the OP describes it should be fine. Source a battery that will fit the bike properly in whatever wh rating you feel you will need factoring in the pretty much global 15wh/mi into the equation. Batteries are heavy and no need to carry around more than you will need. Want more later, get another similar or even smaller wh version to use as an extender. Choose a torque sensing bb from AliExpress. Other than building the motor into a wheel installation is pretty straight forward and can be accomplished with standard bicycle tools.

 

[tomjasz]

I know you aren't interested in building. However, the little Bafang and GBK geared hubs are pretty lightweight (5 lbs GBK) and adequate. torque sensors can be installed too. I bought a GBK GD just to finally see what's what. A neat little hub drive!

 

[Dewey]

The other replies are right, the power you need for a single-speed e-bike to climb the hills you describe would best be provided by a conversion kit. Since you don't want to do the conversion I suggest contacting a shop that specializes in conversions and asking if they can fit a torque PAS sensor to a high power kit, and fit it to a lightweight single speed pedal bike, for example this one from Decathlon, although on this bike you should consider asking a bike shop to replace the fork with a disk brake compatible fork and have them upgrade the front brake, also fitting two torque arms to help prevent the steel slotted axle spinning out of the horizontal dropouts on the aluminum frame. This shop in Medellín will convert a pedal bike with a 1200w kit with a throttle and cadence sensor, if they don't have what you want you could ask if they can source the kit, controller, and bottom bracket torque PAS sensor, ordering the parts from China via AliExpress.

 

[Ben J]

If Specialized made a Turbo Vado SL with the automatic shifting IGH that might be the closest to your requirements.

 

[Marquezdl]

I am a Luddite, old and cranky, and I abandoned Facebook several years ago, so I cant even see which bike shop in Medellin you are referring to. There are probably several hundred. Thanks for trying, but I do not have any desire to pursue that route. If I do opt for that, I have 2-excellent lugged steel frames made for me by Bill Davidson in Seattle. Both are currently configured with internal hubs, chain drive, and rim brakes. One is a Rolhof, the other is a Shimamo Nexus 8. Those are the bikes I Migrated to from my singlespeed when my knees made riding up and down the hills in the Puget Sound too painful. Those years of fixed gear, then singlespeed, then internal hub bikes, firmly fixed my dislike for derailleurs and cassettes.

 

[Dewey]

I hear you about the knee pain. I started by converting a bike with a derailleur but found I kept forgetting to downshift and stopping in too high a gear when riding on the street up hill. After one too many slow crunchy hill starts I tried a Nexus 8 IGH so I could shift down when stationary but I broke two of them with my BBS01 motor so I had my shop fit an Enviolo Heavy Duty CVT last year and it's held up well so far. Recently I tried my first single speed e-bike with a hub motor and a torque PAS sensor and I enjoyed riding it up hill. The manufacturer chose to fit a higher voltage 52v battery with a low 7a current controller setting which means the motor won't overheat when going up hill, plus a torque sensor. I thought the torque sensor was well tuned and could get going even from a stop when facing up hill. A US brand that does this is Electric Bike Company who from this spring have introduced optional torque PAS sensor on their single speed cruisers.

 

[mschwett]

I have been looking at a lot of ebikes, and I havent found one that is “ just what I am looking for” yet.
here is what I am looking for:
singlespeed configuration
rear hub drive
minimum of 45 nm torque
torque sensor
disc brakes
total weight less than 10 kg (44 lbs)
could be either belt or chain

I am a long time bicyclist now 73 and my legs, knees, and lungs ain’t what they used to be.
I rode fixies for a few years, then switched to singlespeed for about 10 years, then went to IGH. I personally do not like derailleurs.
I live at about 1650 meters (5400“) and the hill up to my place peaks at over 25%.
on my regular bicycle I can just make it up that hill without stopping on a good day. I have a Specialized Turbo Vado and its an AMAZING ebike, but I would be a lot happier with an ebike that is 10-15 kg lighter and more like my old singlespeed DeRosa.
Any suggestions?

why not give the ride1up roadster a try? it’s inexpensive and pretty much meets your specs other than the torque sensor. do the easy no-throttle conversion and maybe the PAS settings are flexible enough to get what you want?

there are an increasing number of hub drives bike with torque sensors, but the exact combination you’re looking for doesn’t seem to exist yet.

the rize fixie is also very similar. 34lb, 45nM, belt/singlespeed, no throttle, but it’s based on a cadence sensor.

or… since you have a vado and are familiar with the system, get a vado SL and convert it to single speed! that would be a fun bike. the rear wheel should be easy, not sure how readily available a belt cog for the front would be. veer might have a kit that would work, probably easier just to go with a chain.