New setup idea

[dimi229]

What do you think about this idea?




With this setup and 14,2v battery (and no load) the wheel spin with 26,2 km/h (bike computer read).


Motor: ROXXY 5055/45 : 8 ... 30 V, 9A-20A (60s), 100 rpm/V (no load), 85 rpm/V (with load), max 600 W, 6 mm shaft, 290 g.


P.S.: how can I atach a movie?!

 

[vanilla ice]

Cool setup.

Post it on youtube.

 

[EVTodd]

Interesting idea. Kind of reminds me of that dual motor French friction drive system.

Is that some sort of belt around the pulley?

My only concerns would be about wear on the rim's sidewall (only time will tell) and the amount of load on the motor's bearings. I think you'll have to support them somehow or they will wear rather quickly.

I'm very interested in seeing the video and hearing what kind of performance numbers you are getting. I love seeing simple, efficient setups like this. After all, that's what bikes are all about.

 

[swbluto]

If you want to add a youtube video, you copy and paste the youtube address and delete everything so only the number-letter combination after "v=" is left behind. Example...

http://www.youtube.com/watch?v=tx12YI6gxnI is the original address(It's the URL).

You wanna change that to...

[youtube]tx12YI6gxnI[/youtube]

The result is this...

[youtube]tx12YI6gxnI[/youtube]

 

[swbluto]

Also, not a bad idea at all! I'd imagine it'd be effective when the rim isn't wet which would seem to restrict it to sunny days, but it's pretty simple and nice and the gear ratios are all there. Now only if somehow I could make the rim some kind of gear-track(using like rubber HTD bumps/grooves or something) and then motor attachment would be a "rubber HTD gear" of some sort, you'd have something that'd work in all terrain and it'd be pretty simple! Add one motor on each side (or possibly two gears driven by one motor?) to make it "balanced" if the "side-load" would be too much for one.

But, oh gee... how did you mount the motor?

Man, I'm completely surprised at the innovation being thrown at mounting exterior motors. Well, on one hand, not really as "necessity is the mother of invention" and people need to mount motors! But, on the other hand, it seems there was generally no innovation in mounting a hub motor but that's probably because the simplest way was the most effective and easiest. :lol:

 

[EVTodd]

I was looking at this again and I'm wondering how much the rim would flex when you actuate that pulley on to it. I assume it's moved by a brake cable?

From my experience unless you have very beefy dh rims (or smaller diameter bmx rims) they are pretty easy to move from side to side. Like swbluto was saying... Maybe a dual motor setup with one on each side. I would be a bit nervous about putting force on one side only. Think of it like using only one side of your bike's brake all the time.

I would also think you would be scrubbing the rubber off that pulley rather quickly. Wouldn't the rim try to pull the front of the pulley down with it (if that makes any sense)?

 

[dimi229]

First of all - it's still far away from final setup. I still need to solve a number of problem but I didn't have much free time

Yes I love it too :wink: . I want to find a simple solutions for add a little e-help on hills and eliminate complicated setups with reductors or hard to procure (or make) pieces and I don't want to modify much the bike... after all a bike NEED to be a bike

About the wearing the rimm - isn't wear when you brake ?!

About side-loading - is absolutely necessaries to put in oposite side at least one free spining rubber pulley (or better - another motor).

EVTodd:
- the pulley is taken from copiator parts - yes it had a rubber band on it.
- yes it's moved by a brake cable - this is one of the problem - it doesn't move much for sufficient press on rim but i want to find a solution for this because I want to keep this kind of coupling (for eliminate freewheel too - when you need help on hills... press front brake)


P.S.: sorry for my english - I hope to understand me.

 

[dimi229]

[youtube]Mac52pr_nJA[/youtube]

Sorry for quality of video - it's made with DC.

(in reality it's not that loud that motor at it seems - I don't know why it is so loud in video - in fact it's pretty quiet)

 

[dimi229]

the bike is this: http://www.bhbikes.com/en/catalogo/2009/mountain%20bike/OVER_X_54_2009.htm

 

[paultrafalgar]

Sensational, dimi229! Well done. Have a look at:
http://www.cybien.fr/

 

[dimi229]

oo... Surprise! I didn't know about "Cybien". It has very good autonomy.

You know what kind of motors is on Cybien - brushed or brushless?

 

[deecanio]

Hi Dimi229,

what a nice simple setup
i wouldn't worry about the noise in the video, anyone who has done a video knows the motor sound gets amplified many times, also your english is fine, we understand
I'll take a look at the vid when i get home but for sure this is a good idea.
I agree with you in that the brake causes as much wear on the rim as the motor would but the brake applies pressure from both sides, something you already said you need to look at is powering from both sides too.
Theres a lot in this design though imo and it could be modded to be a really clean setup, good work!!
Just looking at it is making me think wouldnt it be cool to have a twin motor setup, one each side and then instead of having friction to the rim maybe have a "gear" with teeth on the rim both sides? mmmmm.

Cheers,

D

 

[dimi229]

Oh yes... it would be "super-great" if could have gear with teeth.

(in the other side u can put a dynamo :wink: for the pressure)

 

[deecanio]

mmmmmm.

i wonder if you could have a rim "gear" machined with a pitch to match the output gear giving a ratio of 30-1 ish????
if you could have it made you could weld it (or whatever) to the rim of the wheel and you could use that whatever the weather, no slip ever
it's an interesting thought>

Cheers,

D

 

[etard]

great work Dimi,

I like this idea, however for the sake of simplicity, I would recommend just using a friction roller that you could manually slide on/ off the tire, support the roller on both ends with high rpm bearings, then the motor would have very little sideloading. It could be as simple as using aluminum bracing across the fork legs like this:

And then maybe mounting it to slide up and down with a handlebar mounted brake lever that locks out, like this:

http://cgi.ebay.com/bicycle-Motoriz...oryZ7295QQssPageNameZWDVWQQrdZ1QQcmdZViewItem



I began something very similar using a tube with bearings pressed on and this roller with one-way bearings from the EV Warrior, I lost interest, but will eventually put it on a super light setup to assist on hills. Also, much of this has been discussed here:

http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=6877