New type of power transmission

Hello guys I am new here, but I would like to share with you my idea
In my opinion hub motors are too heavy so I decided to build sth using RC motor (but I didn't yet, that's only my idea).
I know that engines used in roller solutions are light-weight but roller often slips or damages the tire (obvious truth).

I would like to transmit power from engine to wheel rim by pulley. How? I would like to transform wheel rim to pulley too. How? Well I was thinking of attach timing belt to it but it would be difficult to modern V-shaped rim (I am not the first one who came up with this idea - https://endless-sphere.com/forums/viewtopic.php?p=27329#p27329 ). But I have a simple solution put on rim an epoxy putty and shape it by pulley. It should be quite hard, shouldn't it?

Light weight is one criteria, another is costs. I would like to use an engine as cheap as possible (with low KV of course). Now I need to choose an engine and pulley to it (but diameter must be around the diameter of engine, better slightly smaller then bigger). http://www.hobbyking.com/hobbyking/store/__45281__4114_320KV_Turnigy_Multistar_Multi_Rotor_Motor_With_3_5mm_Bullet_Connector.html
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=36413 (this one seems to be the best for me)
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=42029

I would like to buy some standard throttle and replace a potentiometer on servo tester circuit. I hope it will not be difficult. And as ESC I would like to use sth that can handle 60-80 A. I know that some of ESC allow to use soft start I think I should take this feature into account.

I would like to use my bike everyday, not to fast, around 20-25 km/h and I don't need long distance 30 km will be enough.

What do you think?

Whoa, much trouble on the horizon for you. The first thing is, I don't what you mean by "Epoxy Putty," but I know it can't be good. The pulley you're talking about making wouldn't last long at all.

There's all sorts of ways that people are already putting together what you want. Just needing some research.

[youtube]TOIefF80Lzs[/youtube]

adluvatan. See pictures and links to lowracer's V-belt drive articles here. He uses 2 rims glued together with J-B Weld.

I just ran into a guy that liked my bike, and invited me to to his house to check out his totally badass leaning trike he had made, with rear wheel drive. He was using a rim glued to the drive wheel method, and a washing machine belt to the motor. It was sweet...6 or 7 leaf modules, Goodyear airbag suspension, including one under the hinged seat. He also had an open wheel, twin motor race car two people could lift up. Four wheel independent suspension...also badass. I said ever get on endless sphere? He said "huh? What's that?" The people you randomly run into around here never ceases to amaze...

AussieJester and 1000W both made up custom toothed pulleys by casting epoxy teeth onto a blank pulley.

Gregg Berkholtz did a Bacchetta highracer in 2008 with a toothed belt drive from these guys.

http://www.bikeengines.com/

His is a gas/electric hybrid.

http://www.evalbum.com/2249

Thank you for all your replies. First of all I don't want to use any V belt (because of power loose of course). All hose big wheels attached to normal wheel looks really bad and I guess it not very light-weight solution. I think that it works well only in longboards. I see that only Gregory understand more or less how epoxy can be used in my idea (but epoxy putty is sth different then resin).

But... I came up with another idea. I typed in google "sth better then epoxy putty" and I discovered polymorph. I just ordered 125 g for 5€ And I will experiment with it. Maybe it will be strong enough to apply. It is very easy to mold and repair, that's main advantage. On the other hand I expect poor adhesive properties to aluminum rim. We will see, I will try.

But, any way: now my biggest problem is to choose a motor. I have to consider this topic closely. I have one month to build working e-bike

[youtube]https://www.youtube.com/watch?v=IhVuc6RNyaw[/youtube]

adluvatan said:

But, any way: now my biggest problem is to choose a motor.

Click to expand...

You think motor choice is a problem only because you haven't yet dealt with getting RC motors to run from controllers that don't just explode randomly.

The motor is a stupid simple dumb robust part, there are dozens of motors that are amazing from a motor spec perspective.

Getting a motor + controller pair that work well together is the most critical aspect of picking a motor.

IIRC, some folks have had luck with Justin's new FOC controller on RC motors. I would start there and work backwards for a motor option that makes best use of the controller. I say this only because I personally ended up with an impressive collection of RC motor paperweights (because nothing available could drive them in a non-propeller-load application) and a large box of stinky charred controllers when I played the RC motor bike game years ago.

For example: if motor is around 60A I would use ESC around 100A to avoid constant overheat. Anyway it is possible to burn a motor with 100A so I would like to use a 60A fuse. Will it help? Or I am wrong? I am aware that it will be impossible use full throttle to start from a parking. I guess I will have to help with pedals to reach a speed around 3-5km. Fortunately Amsterdam is a very flat city.

I would like to have an A-meter visible all the time.
And I hope that heli mode will help a little in motor control.

Castle Creations RC controllers work just fine in ebike applications. I'd still favor Justin's FOC unit if you're confident you can set it up to handle your motor, but RC controllers aren't all going to burn up.

Ralith said:

Castle Creations RC controllers work just fine in ebike applications. I'd still favor Justin's FOC unit if you're confident you can set it up to handle your motor, but RC controllers aren't all going to burn up.

Click to expand...

Except that I've personally watched at least 5 Castle controllers just explode while riding. Thud has a HV160 exploding between his legs on video at the deathrace.

I've heard the Vedder is drastically better than anything Castle as made, but the Vedder is still lacking a real thermal path if continuous power matters for the application.