Still searching for the perfect ultra-light ebike kit for road bikes — here’s the idea in my head

[PedalUma]

motor magnets

It is just a spoke magnet to count rotations and to display speed. Also it can be input for smoothness or perkiness.

 

[Catalyzt]

Do people actually ride bikes with front motors? They always seemed an odd throwback & a bit dangerous with the weight positioned there. Feels odd the power not coming through the pedals. But to each their own. And obviously the market for lightweight e road bikes will be different to front hub bikes.

It really depends on how you are using them. I felt that mine gave me really good service for two years-- I was pushing it past its limits, so it had a shorter service life, but for me, the weight distribution was not problematic at all. Here's why:

* My donor bike, a Trek 930, was relatively light to begin with, 30 pounds before conversion, 40 pounds after, most of the added weight was battery.
* The front fork was also steel, so it could handle the rotational stress.
* The motor was not very powerful, so there were no issues with twisted dropouts.
* The bike had a MegaRange granny gear, so it could do 15% no problem.

The handling, surprisingly, was better with the motor than before it. Exiting a curve, and applying power to both rear and front wheels, you could really pick up speed very quickly. Often, I'd lean the bike way the hell over-- so far I'd have a pedal strike if I pedaled-- then give it a little kick from the throttle to get through the second half of the curve, and start pedaling as hard as I could as the bike began recovering from the turn.

With a heavier bike, the motor wouldn't have been powerful enough to make much difference. Aluminum or CF forks, yeah, it could have been dangerous. And without the granny gear-- and a triple chainring on the front crank, with a pretty small inner ring-- it would have stalled out on the hills.

It WAS alarming on some steeps, before you got the hang of it, because the front wheel would spin a bit. You had to get out of the saddle and keep your weight over the bars. But it certainly would go up grades that were far beyond what one would expect from a smaller motor...

For a couple of years, anyway!

 

[stompandgo]

Often, I'd lean the bike way the hell over-- so far I'd have a pedal strike if I pedaled-- then give it a little kick from the throttle to get through the second half of the curve, and start pedaling as hard as I could as the bike began recovering from the turn.

That sounds like hella fun.

 

[JRA]

Do people actually ride bikes with front motors? They always seemed an odd throwback & a bit dangerous with the weight positioned there. Feels odd the power not coming through the pedals. But to each their own. And obviously the market for lightweight e road bikes will be different to front hub bikes.

I have built 3 different 1000w front hub motor road oriented bikes since 2016, the one in the pics in 2017 was #2 a CL Specialized with a Grin All Axle motor. They all used a throttle and cruise control via the GRIN controller with no PAS. All had Schlumpf speed or high speed drives however. All weighed in around 40lbs with 15ah batteries and would climb anything and I was never at a loss for traction as I was in tune with loading up the front end when necessary. My first effort was a Motobecane with a CF fork btw and it never showed any signs of failure. At 15wh/mi they would average about 19mph in hilly varied surface terrain. If I was going to build a road bike today I would follow the exact same program as I found that separating my cadence with that of the motor to be a distinct advantage.

However my eMTB has torque sensing PAS and wouldn't have that any other way as my cadence varies so much off road comparatively. YMMV of course but don't think it doesn't work.

 

[PedalUma]

All I need to do is shorten the display wire and add the speed sensor wheel magnet to a cargo bike with a DM02. I just tested it. Lovely. Better than any in store bikes.

 

[mschwett]

Do people actually ride bikes with front motors? They always seemed an odd throwback & a bit dangerous with the weight positioned there. Feels odd the power not coming through the pedals. But to each their own. And obviously the market for lightweight e road bikes will be different to front hub bikes.

i have a commuter with a front 500w motor. ride it up steep san francisco hills all the time, sometimes with a kid on the back! in a wierd way, it’s better than rear drive if you’re pedaling hard because it makes the bike two wheel drive.

the only time it feels really wierd is when you’re turning and not pedaling too hard, sort of a torque steer effect.

it’s definitely a very cheap and simple system, keeps the entire drivetrain and rear wheel exactly the same as a traditional bike.

 

[Catalyzt]

the only time it feels really wierd is when you’re turning and not pedaling too hard, sort of a torque steer effect.

Yeah... probably more of an issue with high-power motors but even with my dinky Hilltopper, I did notice a little of that effect, though only at low speed. Even so, it quickly becomes instinctive balancing the power by putting more grunt into the pedals. It was more natural than I expected it to be.

 

[kevinmccune]

Yeah... probably more of an issue with high-power motors but even with my dinky Hilltopper, I did notice a little of that effect, though only at low speed. Even so, it quickly becomes instinctive balancing the power by putting more grunt into the pedals. It was more natural than I expected it to be.

you said it.