Corovelo

[Grant-53]

Every little bit helps.
https://www.bing.com/videos/search?q...092B&FORM=VIRE
Compare with sailplane fuselage of Bowlus BA-100.

[Ecky]

The changes Grant suggested seem to help with high speed stability. Will be getting wh/mi numbers soon.

Yesterday evening, I put together my light control box. I'm still missing the 3-pin JST connector I plan to use for the turn signal, and the actual physical switches which will be installed on the handlebars.

This will be used to power and connect a motorcycle headlight, tail lights, brake lights and turn signals.

[The Toecutter]

Are you using a MAC hubmotor by chance? Any plans to add ferrofluid?

[Ecky]

Yep, it's a MAC. Pretty sure ferrofluid would be a disaster in a geared hub motor. My reading suggests that it adds significant drag (and lost efficiency) even in direct drive motors, and geared motors have a lot more in the way of moving parts inside. And anyway, I'm not having any heat problems with 3000w fed only for brief periods. I destroyed my first bearing hitting a pothole at close to 50mph though, and have had issues with the phaserunner. It's not happy with a 5000rpm motor running at both high current and voltage, and it's going to take a lot of tuning to minimize instantaneous phase overcurrent faults. I think if I were to do it again, I might go with something else, maybe an infineon controller. Or, considering how unrealistic it is to pedal at higher speeds, maybe a direct drive motor with the phaserunner.

[Ecky]

Working turn signals and brake lights:

https://youtu.be/aOjCmHE5Q7Y

[The Toecutter]

Originally Posted by Ecky

Yep, it's a MAC.

Do you know what winding it is? 6T? 8T?

My reading suggests that it adds significant drag (and lost efficiency) even in direct drive motors, and geared motors have a lot more in the way of moving parts inside. And anyway, I'm not having any heat problems with 3000w fed only for brief periods. I destroyed my first bearing hitting a pothole at close to 50mph though, and have had issues with the phaserunner. It's not happy with a 5000rpm motor running at both high current and voltage, and it's going to take a lot of tuning to minimize instantaneous phase overcurrent faults.

A direct drive motor can run at much lower rpm. If you have a 26" rear wheel, 388 rpm is 30 mph.

I think if I were to do it again, I might go with something else, maybe an infineon controller. Or, considering how unrealistic it is to pedal at higher speeds, maybe a direct drive motor with the phaserunner.

I like the 1500W Leafbike motor.

https://endless-sphere.com/forums/vi...p?f=30&t=66489

With 48V, roughly 90% efficiency at 1kW and 390 rpm in a 26" wheel, the manufacturer's specs having been confirmed by 3rd parties on endless sphere. Without any mods, they can reliably and repeatedly handle short bursts of 4 kW and 1.5kW continuous, but with modification(fans, ducting, ferrofluid, ect), 10 kW peak is possible. It's also very inexpensive at under $300. My only major gripe is that it is 16 lbs of additional rotating mass with which to accelerate while pedaling up to speed should you choose to turn the motor off or run out of battery or for whatever reason need to move it with the motor disabled.

Supposedly, its drag isn't very noticeable when pedaling.

[Ecky]

Mine is 8T and is the latest gen, with composite gears and a temperature sensor. I cracked it open after a few hundred miles and the gears all still look good, but I'm probably going to run it at slightly lower power to protect clutch and gears. Geared hub motors feel a lot more torque-y at low RPM than direct drive, and tend to have better efficiency at lower speeds, so I probably don't need nearly as many watts anyway.

At first glance the Leafbike motor looked like any of the other eBay hub motors, but the efficiency graphs suggest otherwise. I might snag one to try.

[The Toecutter]

That MAC motor you have is probably around 75% efficiency in your application, so the improvement in range and reduction of heat will be very noticeable.

Without suspension, I wouldn't want to do more than 20 mph on some roads where I'm at. Any data on the efficiency of the shell yet?

[Ecky]

I broke one of my motor bearings so I'm waiting on a local bike shop to get one in. ^^

Always something.

[Ecky]

Originally Posted by The Toecutter

Without suspension, I wouldn't want to do more than 20 mph on some roads where I'm at. Any data on the efficiency of the shell yet?

Preliminary data!

20mph - 15-16wh/mile
30mph - ~21wh/mile

Temperature was just about freezing, and there was a crosswind gusting to ~10mph which was pretty scary at 30.

EDIT:

So that's effectively 2,250mpge and 1,600mpge respectively.