spaceman
10 W
Here is a very quick and simple calculation for torque, which shows that with the device installed and using 6th gear (21T in this calculation), you actually get more torque that using 36T sprocket without the device.
Bikeon, "cassette drive" torque sensing motor
- Thread starter adrian783
- Start date
spaceman
10 W
This was the first installation on 11 speed cassette. The design is tweaked to avoid all these adjustments. Installation on 7-8-9-10 speeds did not require these adjustments.
Gruesome
1 kW
Thanks for all the comments and pointers.
- The lowest gear I have with the cassette as-is (not reordered) is 34 front to 21 rear. So the lower third of the original 4.5:1 50T/34T front x 34T/11T rear gear range is gone, and it's now a 3:1 (or more precisely 4.5:1.6) ratio. Since the motor (hopefully) can bring up the climbing speed (to be verified), this might be ok. I'm still going back and forth about how I feel about losing almost half the cassette.
- Readjusting the derailleur stops for the BikeOn per se is not necessary. I had to readjust for the 1 mm spacer, but the bike is useable without the BikeOn with that spacer in place. The readjusted low side (big sprocket side) stop is not really functional, since the derailleur has to lean against the BikeOn rail extension anyway to be able to cleanly shift into the lowest gear. Update: I just checked, and I had actually NOT adjusted the inner stop for the BikeOn. (I did adjust it for the 1 mm spacer.) As I said, the derailleur stops anyway against the baseplate extension (which I assume is there for exactly that purpose).
- If the 21T sprocket in the rear turns out to be too high (small) for climbing, I could rearrange the cassette to 34-30-27 (fixed cluster on common spider)-23-19-25-21-17-15-13-11, so that 34T:25T becomes the lowest usable gear.
- BikeOn also makes nice bottle holder batteries with steel enclosure, up to 350 Wh capacity. I was aiming for larger range though. If the system really only uses 6 Wh/mile with my settings, I might be able to get away with a smaller battery.
Last edited:
raylo32
100 kW
Indeed, the wide range of cycling hardware out there makes designing a universal drive solution like this very difficult. I believe you have done pretty darned well, however, and expect it to only get better.
lnanek
10 kW
- Joined
- Sep 26, 2022
- Messages
- 522
I never bother changing gears on my rear motor hub bike, personally. So losing half my gears wouldn't matter to me. I let the motor handle anything that would need a low gear like starting from a stop light anyway. Only gear I use is highest, to assist the motor and get exercise at top speed, which is what I try to be at the rest of the time to minimize my 20 mile commute to work.
It does feel like this could be competitive with a rear hub install re simplicity since that involves a torque arm or two, which I bolt in, and routing the electric cable from the axle, then all the normal rear wheel replacement steps.
Deal breaker for me putting it on my acoustic bike and having a backup for my ebike is just cost, I guess. Most of my rear hubs were like $50 off Facebook marketplace used, I could probably get a decent one new for $150-300 off the slow boat from AliExpress, or some premium option from Grin for $700. Bikeon is over a thousand... I'd have to ask my wife before spending that much.
It does feel like this could be competitive with a rear hub install re simplicity since that involves a torque arm or two, which I bolt in, and routing the electric cable from the axle, then all the normal rear wheel replacement steps.
Deal breaker for me putting it on my acoustic bike and having a backup for my ebike is just cost, I guess. Most of my rear hubs were like $50 off Facebook marketplace used, I could probably get a decent one new for $150-300 off the slow boat from AliExpress, or some premium option from Grin for $700. Bikeon is over a thousand... I'd have to ask my wife before spending that much.
Mongo
1 kW
raylo32
100 kW
Waaaay back in the day there was a mail order bike store... IIRC this was before online shopping was mainstream... that would send fake receipts for about 50% of the actual costs to show the wife. They didn't stay in business long, unfortunately.
Note BikeOn's battery is 36 V 7 Ah (250 Wh) with a 20 miles range advertised. The UPP 48V 7 Ah 336 Wh may give you the range you need? My bike with mid drive and battery is 42 lbs. I weigh 115 lbs. I think your Canyon gravel/ street with the BikeOn (minus battery) is under 30 lbs?
How's the user interface on the phone? Is it easy to use?
Last edited:
This thread is a really good example of how to deal with ES from a vendor's POV!
- Joined
- Aug 8, 2022
- Messages
- 1,158
While I am not personally interested in an ebike conversion project, I've followed this thread religiously because I've been blown away with how thorough, responsive, helpful and patient this vendor has been with everybody here, consistently. You don't see that often. Hat's off, @spaceman
spaceman
10 W
I really appreciate all the comments and involvement from each one of you. You help us get better. Thank you!
Gruesome
1 kW
A few comments and ideas while I'm waiting for some parts Aram is designing and having machined (I guess this will be version 3, or 2.1; not sure about the numbering scheme):
- the BikeOn phone app 'Ride' page right now is absolutely minimal; it just shows the speed as perceived by the motor (i.e. drops the speed to zero when coasting), and allows to cycle through the power settings.
- It would be nice to add some pages showing estimates or measurements for motor power, human power, battery voltage (I attached a battery volt meter, which I find easy enough to translate to charge and energy left, and which I actually prefer over a rescaled 'battery meter'), maybe also averages for the current ride for average motor and human power, and speed.
- I think it might perhaps make more sense to make the BikeOn quantities mentioned above available to other programs/apps, rather than trying to develop a standalone do-it-all app.
- To minimize play in the rotor-to-sprocket clamping mechanism (the black toothed brackets), maybe include two silicone strips or similar squishy inserts that go between the sprocket and the black clamps. I tried hot glue in that location today, and something of that consistency seems to work to take out the play. This would be a consumable, and probably not make much sense for people who install and remove their motor all the time.
- While I appreciate the design approach of using soft mechanical links where possible, it might be good to fix the lateral motor/baseplate position relative to the chain stay and wheel. I would not mind having to install a semi-permanent attachment bracket or sleeve to the chain stay that the BikeOn baseplate slides or clicks into, and that prevents the baseplate from moving towards the wheel.
- The cable routing with the adjustable silicone loops works well for me.
- I also like that there is a standard automotive fuse holder integrated into the cable, close to the battery.
- There is an audible spark when connecting the motor to the battery. I don't know how hard it would be to integrate a 'soft connect' feature into the controller board. Is there an XT60 version with spark suppressor? I know it's an available feature for XT90.
Many cassettes are built of multiple sprockets and spacers. At the risk of moving away from the original design objective for this motor (easy to fit with no mechanical changes to the bike), maybe there is a place for a drive ring that replaces the innermost sprocket with a single assembly. This might be accepted by users who would re-stack their existing sprockets to achieve a wider gear range anyway.
How do you find the torque sensor?
Yes, but that is just due to the ergonomics being totally different, Surron are not really like bikes either, despite that market wanting to make them so, to bend the rules. Then add on the effects of higher speeds and the expectation of travelling much longer distances on motorcycles, of course they diverged immediately. Possibly even faster than horseless carriages diverged from horse drawn vehicles.
Gruesome
1 kW
I think the clamping can be improved so that fiddling with the cassette is not necessary. You need a few tools to remove and remount a cassette that we might think of as normal to have, but even-more-normal-than-us people might not: cassette locknut wrench insert, cassette locking chain whip/pliers, or even a torque wrench.
Seems to be working fine for me. But maybe a simple throttle would as well. As I said before, I have only a little bit of experience with harsh uphill starts on a borrowed e-MTB. I have not experienced that with the BikeOn, but then I haven't tried starts at full motor power. Otherwise I really have nothing to compare to.
I did a quick test today to check whether I solved the spoke interference problem (sadly, I did not), but I definitely can say now that the motor output torque does increase with human torque: the interference is due to a secondary (or tertiary, depending on how you count) moment resulting from the motor torque, and sadly it scales (gets worse) with my pedal pressure. (By secondary I mean a moment that occurs due to a constraint placed on the primary moment, in this case the motor wanting to climb upward.)
Aram should comment if he wants to, but I think he is making good progress with maximizing clearances and also adding a stiffer lateral motor restraint. Turnaround will be a few weeks, as is usual for machined parts.
I think it would help if somebody with a modern 1x12 drive train could test the system as well. (Of course one could argue that Aram should be that person...
)
Last edited:
spaceman
10 W
It is V74 major 21 minor on hardware, V14 build 24 on software and 4.17 on firmware.
We've built over 100 different prototypes before the first production run.Yep, already addressed and tested.
Working on it. These issues arose with 11/12 speeds; 7-8-9 and 10-speed cassettes have more space and are more forgiving of the small misalignment of the device. Nevertheless, it is going to be resolved.
Try to connect the cable to the device before turning the battery on. There is a large cap which is charged when the cable is connected to the battery and the battery is on, so when you connect it to the device it discharges quickly, that is where the spark noise comes from.
Normally there is a discharge resistor which quickly discharges the cap once it is unplugged from the battery to prevent that spark from happening.
All the groundwork is done to deploy more sophisticated version of the app; the device measures most of the parameters you mentioned. We just need more time and resources. Probably another month or so (maybe even sooner) and I will release a more detailed version of the app.
Thank you!
spaceman
10 W
We also have a couple of local riders who help us with testing. A little bit of time and we will get there.
Gruesome
1 kW
I was just searching for Bimotal, and ran across this post. Compared to BikeOn, it seems they went down a dead alley, even though the number of people involved seems larger.
- What makes them think $2000 is an even remotely acceptable price for getting beta testers involved?
- Why did they pick external post-mount brakes as their only attachment method?
- What's the point of offering a $1/Wh battery, when most batteries are half as expensive, and you can find some here for 1/8 the price?
spaceman
10 W
These are two very different systems with different design intents. BikeOn was designed initially for bicycle commuters; it had to be lightweight, easy to use, and powerful enough to get to the office without breaking a sweat.
That was one of the reasons why we designed BikeOn for a max sprocket size of 36 teeth. As it turned out, there are many other user segments interested in our device. Our users currently include recreational cyclists as well as commuters.
Mountain bikers have very different needs: high torque and power levels, and responsive suspensions with a good feel on rough terrain, to name a few. I have been talking lately to a lot of mountain bikers, and we do have some very interesting design work going on in that segment, but that is not the focus currently. And I don't see mountain biking as a major use case for the current model of the BikeOn device.
But don't forget you get a new brake rotor included in that. It may not be the size you want, but no other kits have that...
Edit: Sorry, wrong about that. Skarper also comes with a brake rotor. Which is just as well, as it is just as expensive.
Last edited:
Yeah, but do you think the ugly stick they used on that battery pack was a cheap one?
I can't speak for the forum but i'd bet we'd like that, and also more like 1000w of power.
The other unit is nice ( something that sends power to the disc brake always made sense to me because it can handle a LOT of power ) but the price is beyond my pain point!
Last edited:
Gruesome
1 kW
Has anybody else bought a BikeOn in the meantime? I'm currently waiting to get mine back, hopefully with a better fit, but it would be interesting to hear of other experiences with this kit. Has anybody seen any new reviews from bike websites or magazines?
Deacon Blues
1 µW
I'm considering purchasing this kit, but I don't want to be a Beta tester.
It would be a perfect addition to my Defy carbon road bike, but I'm going to wait until all the bugs are worked out.
It would be a perfect addition to my Defy carbon road bike, but I'm going to wait until all the bugs are worked out.
Gruesome
1 kW
Ok, I can see that point. With an 11/12 speed gear you would be a beta tester, I'm afraid. My understanding is that anything below that just works fine.
I'm actually a bit puzzled that I had these problems, because, unless I seriously misread, the Shimano 7-9 speed cassettes & cassette hubs and the 10/11 speed mountain bike cassettes & cassette hubs are all the same widths, and interchangeable. (11 speed road hubs are 1.85mm wider, and from 12 speed on it's a different spline, to allow 10T sprockets.) It must be the slightly narrower sprocket width of an 11 speed cassette that pushes the BikeOn motor back plate just ever so slightly into my spokes.
Aram/Spaceman just notified me that he has the new parts, so pretty soon I should have my BikeOn kit back!
I'm actually a bit puzzled that I had these problems, because, unless I seriously misread, the Shimano 7-9 speed cassettes & cassette hubs and the 10/11 speed mountain bike cassettes & cassette hubs are all the same widths, and interchangeable. (11 speed road hubs are 1.85mm wider, and from 12 speed on it's a different spline, to allow 10T sprockets.) It must be the slightly narrower sprocket width of an 11 speed cassette that pushes the BikeOn motor back plate just ever so slightly into my spokes.
Aram/Spaceman just notified me that he has the new parts, so pretty soon I should have my BikeOn kit back!
