Any bike will do?

[MajorMagnuM]

First off a thankyou to all that have posted great information on this forum. Really instructive and inspiring.

So I'm getting ready to start my first e bike project (I like to research alot first).

I would like to use my bike as the centrpiece but im unsure of its suitability. It is very light (made of scandium - an aluminium alloy i think) and has 29 inch wheels. Here is a link to pictues of the frame.

http://www.ninerbikes.com/air9geometry.html

the fork i fitted wieghed 950g

http://www.bontrager.com/Mountain/Components/Forks/22057_popup.php


I am hoping to fit a hub motor to the bike.
Does anyone have an opinion on the frame - rear dropouts and rear width- are they suitable?

Would replacing the forks with a steel fork be advisable if fitting a front hub motor?

Are there hub motors available that would provide enough hill climbing torque and top speed for a 29 inch wheel?

How strong does a rim / spoke combination have to be to take the load or force of a particular hub motor?
The most most important question last, How BIG can i go?

Any help getting past this proof of principle point would be very much appreciated.
Pie in the sky or a potential really lightweight ride?

Thanks for reading!

 

[BiGH]

yes you can get some motors that can be laced into a 29" wheel and will provide enough torque. Check out the puma motor, and crystalyte motors with higher winding numbers ie 409,411,412 - the higher the winding number the higher the torque, but lower the top speed.

nice bike, if you're going to run a front motor take off and sell the lightweight forks. I ran an aluminium MTB frame with rear motor, and the motor spread the dropouts easily. Light weight bits are great as a bike, but not when you're talking powered, especially high powered. (ie i didn't have a problem at 36v 35a, but at 72v 35a the frame didn't last long!)

I prefer running a rear motor, but then you have issues of weight distribution.

I thoguht a lot about using a light weight bike (even using a carbon frame on with steel front forks, but u know what? the crystalyte motors weigh 8kg, and the batteries are of similar weight. Once u weigh up how much u weigh, the motor and the pack, and then the actual bike itsself, making the bike frame weighless doesn't really change the weight in % very much at all (<5%). And frankly i'd rather save the money to spend on something else, as a steel frame is fine.

 

[Drunkskunk]

Nice Bke. Welcome to here.

I run a 29 inch with a Crystalyte 408/4012 combo motor. it climbs texas hills just fine, but onroad, not very well off road. a Puma would do much better for climbing hills, but there are trade offs.

the 29 inch is just a 700c wheel with a 2 inch tire. the MTN bike tread is very inefficent, so I run 42c semi slicks tith just enough knobs on the side to keep me moving on trails.

The rim I have laced on the rear wheel is what came with the motor from Poweridestore.com.its an aero style and very strong, laced with 13 guage spokes. the front is a Velocity Dyad. both take the abuse of me plus the motor's power, and all the extra weight without issue.

With that short stack heigth on your headset, and the aluminum frame, I'd skip the front hub idea, even with a steel fork. rear hubs make the bike tail heavy, but I prefer the feel of read drive. its a lot stronger, and the frame can deal with the stresses better.

 

[Link]

Hey, that's what I was going to do to my spokes. They look even better red than I thought they would...Must look for a can of spray paint...

Oddball question: Has anybody out there thought about/gone about painting something onto their hub motors?

(Sorry if I'm thread-jacking )

 

[BiGH]

no but i'm going to paint the whole bike (inc hub motor) black

 

[tailwind]

Has anybody out there thought about/gone about painting something onto their hub motors?

Yes, and its a classic.

http://endless-sphere.com/forums/viewtopic.php?t=2241

Greg

 

[Malcolm]

Hi Magnum

That's a great looking bike. To do it justice I'd go for the lightest combination I could find: a rear TongXing geared hub motor and a small lithium phosphate pack. The motor and controller only weigh 2.3 kg. Peak output is around 400W, which isn't a massive amount but they do produce decent torque. If you get one of the slower TongXing motors – around 160 rpm – it should be good for around 20 mph with those wheels.

 

[marty]

MajorMagnuM,
Look at http://www.bionx.ca Got PL350 and love it. Have had no problems. Only complaint is that it is slow. 20 MPH after changing code as described here
http://endless-sphere.com/forums/viewtopic.php?t=896
Goes faster if I pedal. Think it would be faster with a better bike like you got?

 

[MajorMagnuM]

Thanks for all the replies to my questions. Seems rear hub may be the way to go. Was going to put it in the front as i imagined it would give me a more balanced bike. Will do some more research now as proof of principle is there, in that i could use this bike for the conversion which is great.
Will keep u all posted.
next research Brushed or brushless and Tongxing
Tyvm once again!

 

[Malcolm]

There's more about the Tongxin motor here http://endless-sphere.com/forums/viewtopic.php?t=340&highlight=tongxin

I spelled it wrong first time, which is probably why you couldn't find much info about it :?

 

[MajorMagnuM]

HI and thanks for that link to the tox motor.

Having done a bit more research and got more advice about the frame. I don't think its gonna take the power I want to apply over a long period of time, front or rear. My other bike is very slender and would last even less i reckon.

So i'm gonna have to find a ss frame and a big one ( i'm 193cm and 80kg)
for -road work.
-light offroad tow path / gravelly work
Pleaase feel free to comment.


MMag

 

[Link]

That motor with the mice on it...Reminds me...I've seen this really weird clock that is driven by a mechanical hamster.

I think you know where I'm going with this...

EDIT: 10mW mark. Eh...