spaceman
10 W
This device is pedal assist only. I may think about a different device for throttle only usage, but not now.
Bikeon, "cassette drive" torque sensing motor
- Thread starter adrian783
- Start date
spaceman
10 W
Correct.
Frame of the device, not the bicycle.There is a thermal path from the motor and electronics to the frame of the device to dump the heat. Apologies if I wasn't clear enough.
spaceman
10 W
Please see the answer above.
spaceman
10 W
I have no definitive answer for each and every cassette, sorry.
Gruesome
1 kW
Aram, I sent you a more detailed inquiry about clearances and the 'motor mounting plate' thickness via email. Easiest would be if you published a few cross sectional drawings or sketches, so I (and other potential customers) can figure out the fit and cassette reconfiguration options. If you are worried about copycats, you could publish a 'stay clear' outline.
I also suggest you get your motor into the ebikes.ca simulator tool; that would also allow thermal simulation.
spaceman
10 W
Yes, I received it, will reply shortly.
raylo32
100 kW
Yes, but someone who wants or needs to ride on throttle only would not be happy with very minimal power, especially after the motor throttles power down due to heat. As Aram says, this is designed for pedal assist only. I know you mean while pedaling... I was just posting this for the guy who wanted the throttle only function, which IMO would not be wise on a motor this small.
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raylo32
100 kW
Why? if you live in a fairly flat area ( that's most of the world BTW ) and don't have high speed requirements, i don't see why a throttle would be a bad idea.
Tons of ebikes came with 250w - 750w motors back in the day with throttles and no PAS, or PAS that sucked super hard and people would remove it. No problem as long as the motor is tuned reasonably with some thermal headroom left.
The real problem is not pedaling.. this doesn't offload the motor power when accelerating so the motor will make more heat. The answer to that problem is to pedal.
This motor will limit the current if the temperature is too high, if it had a throttle, your worst problem is the controller downgrading the power because it's too hot.
You could get a throttle by breaking the warranty and using an external third party controller just like any motor.
..but this is very new technology to us so i'd recommend not doing that.
Mongo
1 kW
@raylo32, I think this is because the BikeOn design drives off of the (hopefully 25-36T, via sized rotors) inner cog/sprocket, and the narrower your cog/sprocket spacing (worse with more speeds) my guess is more cogs/sprockets are blocked by the design and not usable (and related to limiting the derailleur span).
Shades of compensating for the BBSHD chain line woes, rearranging the sprockets/cogs has been mentioned.
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My best guess..
You use the tallest gear in the stack but some derailleurs might smack the drive ring, so that's why the number of gears you lose is variable... depends on your cassette width/type and the shape of your derailleur.
If you don't have huge hills, you will only need a few gears with this amount of power.
You use the tallest gear in the stack but some derailleurs might smack the drive ring, so that's why the number of gears you lose is variable... depends on your cassette width/type and the shape of your derailleur.
If you don't have huge hills, you will only need a few gears with this amount of power.
raylo32
100 kW
That pretty much defeats the purpose of being able to slap it on, say, my gravel bike with 11-speed Shimano for a ride and then take it off... I mean if I have to restack the cassette. I wonder what cassette is "ideal" for it?
raylo32
100 kW
Yeah, probably don't really need those low end gears. I never use them on my Photon or X1 bikes climbing 10%+ grades and those bikes have 42t chainrings whereas my gravel bike has a 30t small chainring. So that really should be plenty of range even missing 32t and maybe even the next 1 or 2.
Gruesome
1 kW
I'm looking into that for my potential application. My current thinking is that restacking might work if I switch to an 11-to-32 teeth 11speed cassette; but that leaves the question you brought up, namely how usable is this bike then without the motor?
I'm also wondering what the continuous maximum usable power is, for example when going up a several miles long grade. Aram is right that we usually do not pedal continuously, but in that use case (going up many miles long grade) one would (unless one stops and takes a break). Having to take a short break every 20-30 minutes would not be the end of the world, but it would be nice to know beforehand.
Getting this motor into the ebikes.ca simulator tool would be ideal for answering these questions.
Gruesome
1 kW
One question I can't answer from looking at the pictures is: can the chain run over the roller near the top, or is that just a bearing for the red ring, and the chain has to stay clear of it? If the chain is allowed to touch and partially wrap around that roller (green line), the largest possible driven cog diameter that clears that roller is about 135 mm or about 33 teeth; if the chain has to stay clear of that roller (blue line), the largest allowed driven cog diameter is about 104 mm or 26 teeth.
By 'driven' I mean 'the chain can run over it and drive the bicycle'.
By 'driven' I mean 'the chain can run over it and drive the bicycle'.
spaceman
10 W
Chain always passes below that bearing marked on the picture.
I don't know where you are taking these numbers from, but the device accommodates 36 teeth sprocket with no problem, tested.
spaceman
10 W
What are you trying to solve? I am a bit lost here...
Guys, i continue to be on the fence about buying this motor. I don't really have a strong application for it RN, moreso curiousity about this novel drive mechanism, and a want to support innovative companies ( we need them.).
I've PMed spaceman back and forth, and he is an intelligent, no BS, and very helpful dude.
If you are looking at a 500-750w geared motor and want PAS, then this would be a great alternative to that and blow the power/weight ratio of any geared motor out of the water, even my beloved Shengyi SX2.
For cassettes, i would run the highest gear count that fits your wheel. You got 7 speed? use a 9 speed cassette and dial out the last 2 gears - now you have a 6 or 7 speed.
I've PMed spaceman back and forth, and he is an intelligent, no BS, and very helpful dude.
If you are looking at a 500-750w geared motor and want PAS, then this would be a great alternative to that and blow the power/weight ratio of any geared motor out of the water, even my beloved Shengyi SX2.
For cassettes, i would run the highest gear count that fits your wheel. You got 7 speed? use a 9 speed cassette and dial out the last 2 gears - now you have a 6 or 7 speed.
Gruesome
1 kW
I don't mean to be difficult or controversial here. My numbers are coming from measuring the various diameters on the BikeOn website pictures, assuming a red ring inside diameter of 175 mm from a picture that Aram graciously provided me.
I do not doubt that the BikeOn drive mounts without problem on a 36 teeth cog. That is the innermost cog in the cassette, and the cog that the red ring clamps onto with the black teeth.
But as far the maximum diameter of the cog driven by the chain is concerned, a 135 mm / 33 teeth cog seems the maximum that can clear that bearing, judging from the pictures available to me.
If the bearing rotates with the chain, 135 mm diameter or 33 teeth is ok. (I might be off by a mm or two.)
If the bearing (or bearing housing) is stationary, or rotates with the red ring (i.e. against the chain direction if the chain were to contact it from below), then the chain has to have a straight path (tangent) from the top of the largest possible chain driven cog, clearing that top bearing, to the torque sensor. I measure that to be a cog of 104 mm diameter or 26 teeth. Again, I might be off by a mm or two.
I acknowledge that I might be the only one who wants to preserve the slowest possible gear while using the BikeOn drive.
Maybe the continuous power of the BikeOn drive is so large that I wouldn't need that largest cog. I don't know.
What I do know is that I can do a 6.5% grade at about 5 mph with about 60rpm cadence and 34 front teeth and 34 rear teeth comfortably, with both the ebike.ca motor simulator and the An interactive model-based calculator of cycling power vs. speed bicycle simulator telling me I need about 150 W of human power. Clearly I don't want to pedal at 120 rpm and 9.5mph with an additional 150 W from the motor, so I do not need the 34 teeth rear cog, but I would like to know how much headroom I have. If the motor can do 150 W continuously, then a 22 teeth rear cog is fine, and gets me to 73 rpm, which is great.
I do not doubt that the BikeOn drive mounts without problem on a 36 teeth cog. That is the innermost cog in the cassette, and the cog that the red ring clamps onto with the black teeth.
But as far the maximum diameter of the cog driven by the chain is concerned, a 135 mm / 33 teeth cog seems the maximum that can clear that bearing, judging from the pictures available to me.
If the bearing rotates with the chain, 135 mm diameter or 33 teeth is ok. (I might be off by a mm or two.)
If the bearing (or bearing housing) is stationary, or rotates with the red ring (i.e. against the chain direction if the chain were to contact it from below), then the chain has to have a straight path (tangent) from the top of the largest possible chain driven cog, clearing that top bearing, to the torque sensor. I measure that to be a cog of 104 mm diameter or 26 teeth. Again, I might be off by a mm or two.
I acknowledge that I might be the only one who wants to preserve the slowest possible gear while using the BikeOn drive.
Maybe the continuous power of the BikeOn drive is so large that I wouldn't need that largest cog. I don't know.
What I do know is that I can do a 6.5% grade at about 5 mph with about 60rpm cadence and 34 front teeth and 34 rear teeth comfortably, with both the ebike.ca motor simulator and the An interactive model-based calculator of cycling power vs. speed bicycle simulator telling me I need about 150 W of human power. Clearly I don't want to pedal at 120 rpm and 9.5mph with an additional 150 W from the motor, so I do not need the 34 teeth rear cog, but I would like to know how much headroom I have. If the motor can do 150 W continuously, then a 22 teeth rear cog is fine, and gets me to 73 rpm, which is great.
raylo32
100 kW
I totally agree. Spaceman does a great job responding but some of these questions can't be fully answered until we try one. My potential use case would be a 2x gravel bike with 11-speed cassette with 32t biggest cog. Especially for travel so I could take 1 bike and have an analog bike and an e-bike in one. Damn.
And I would have to be able to pop the device on and off with no other mechanical changes since I ride this bike analog a lot. I don't even want to have to run the rear derailleur mechanical stop in to keep it from going too far. So, I'd have to be careful shifting... or maybe the device drive ring would just block it if you tried? Again, have to try one to know.
Since the small chainring is 30t I would have plenty low gearing even losing the top 2 (or 3?). The 30t even with only a 25 cog is still lower than my other e-bikes that have 32t cogs and 42t chainings and they easily climb everything I need to climb... and I never even use the 32t cogs on those anyway.
And I would have to be able to pop the device on and off with no other mechanical changes since I ride this bike analog a lot. I don't even want to have to run the rear derailleur mechanical stop in to keep it from going too far. So, I'd have to be careful shifting... or maybe the device drive ring would just block it if you tried? Again, have to try one to know.
Since the small chainring is 30t I would have plenty low gearing even losing the top 2 (or 3?). The 30t even with only a 25 cog is still lower than my other e-bikes that have 32t cogs and 42t chainings and they easily climb everything I need to climb... and I never even use the 32t cogs on those anyway.
Not looking to buy this drive right now, but i like the design - very pleasing to look at, clever, non invasive. And pretty self-explanatory how it works. Maybe it's explained somewhere why belt transmission is used instead of directly driving the big red sprocket from motor sprocket, but i assume this is because there's less mechanical stress with the belt? Or does it have a different purpose?
Mongo
1 kW
@blinthor, per the BikeOn site FAQ: "BikeOn is designed to be compatible with most standard bicycles with gear size of between 25 and 36 teeth. Currently BikeOn is not compatible with BMX and other single gear bicycles (fixies), Brompton and other folding bicycles, bicycles with belt drives, internal gear hubs and bicycles with a chain guard."
