supr ez friction drive

deacon · #11 (**permalink**) 05-21-2008, 09:55 AM

I might just save my pennies so that when the china girl gives up on me, i can just replace it. Of course as little as I ride it, it might outlast me anyway.

deacon · #12 (**permalink**) 05-21-2008, 02:14 PM

I really want an ebike for my second bike so I continue to test this concept. First of all the friction wheel is very viable. It works well however I have come to believe the motor 250 is much to small. How did I come to that conclusion you ask?

I added a second friction drive motor to the front on the front wheel and the bike just sang along. That was five hundred watts of usable power. I often wondered if 140 watt motor wouldn't be enough and save battery power. Now I know don't waste your time with even 250 watt. It just won't do at all. What one needs probably is 450 to 600 watts for good power and use.

Now about battery consumption it is going to be high. That's the bad news, the good news is that the trailer idea adds very little drag to the bike. You can pack a trailer with sla batteries for the same weight as the flooded ones I have been using. You could get probably thirty hours worth at least.

The controller actually slows down the top speed of the motor. They run better as pulse motors. Both on the same switch seems to work as well as anything.

I am going to hold out for a 400 to 500 watt motor. I'm going to try it on the controller I have and if I burn it up, I'm going to just use the on off switch.
Just thought I would update you on what I have learned about building ebikes without a kit.

deacon · #13 (**permalink**) 05-22-2008, 03:18 PM

I have no idea what I have done. I made about five changes in the ebike last night and now it runs like crap. I removed the 20" front wheel and put the 26" back on it. I hung the motor from the brake hole in the forks instead of onto the forks like i did for the twenty. For some reason know only to god and he wont tell me it steers like a car with a bad steering box. Obviously I did something wrong on the front end. I'm going to string for a powerful motor in the rear and forget the two motor drive system.

deacon · #14 (**permalink**) 05-22-2008, 06:26 PM

If I can get a contest for the biggest dumbass I'm sure I will win hands down. I ordered a bigger engine for the rear drive. I decided it had to be something with the relocation of the front drive that caused the problem. Then wonder of wonders I decided to paint the bike while I was waiting for the new motor to come in. That is when I discovered the problem.

I had reinstalled the front wheel without the spacers that centered it in the over sized frame. The front wheel was rubbing the frame continually. That's why it wouldn't steer and probably why the performance was terrible. I have to wait for the new motor then test it by itself. If the performance isn't what I want, I am going to build a friction drive for the front as well. I have a sprocketed motor so I will just find another scooter drive wheel to use up front to add to the drive power.

I honestly don't think I will need to since I bought a bigger motor and I think the one I have has a reduction gear built in. It might be the controller doing it though. Either way I will know something soon.

**Bikeguy Joe** · #15 (**permalink**) 05-23-2008, 06:50 AM

You haven't won the award yet deacon.