MultiSpeed/HubMotor Design Option

[eP]

...
If there was a real demand, you would probably be selling kits by the container load. The fact is there's little demand, and nobody is filling containers with anything but hub motors. (I could be wrong on this, so anybody feel free to point me to a mass market geared/multi-chain/whatever kit that is available to purchase in container quantities)

Yes You are WRONG on this as producers creating demand not the buyers at this market.
Bike sellers and hub producers have no interest in offering cheap efficient solutions.
They want earn as much many as is possible.
The same way things go at the moto market.
How do you think way new electric cars are so expensive ?
Why big players don't offer cheap kits for electric auto conversion ?
In fact they don't offer any kits.
How do you think: for the sake of low demand ?

 

[Miles]

I think we should divide e-bikes by categories and describe the best options for each category.
Precise description should include motors parameters, loses for heavy load, costs, efficiencies, mechanical mount difficulties and costs, etc.
All positive and negative sides.

In other way we will do futile discuss, comparing good drives for quite different categories.

Good idea.

Could get quite complicated with all the permutations, though...

 

[Lowell]

...
If there was a real demand, you would probably be selling kits by the container load. The fact is there's little demand, and nobody is filling containers with anything but hub motors. (I could be wrong on this, so anybody feel free to point me to a mass market geared/multi-chain/whatever kit that is available to purchase in container quantities)

Yes You are WRONG on this as producers creating demand not the buyers at this market.
Bike sellers and hub producers have no interest in offering cheap efficient solutions.
They want earn as much many as is possible.
The same way things go at the moto market.
How do you think way new electric cars are so expensive ?
Why big players don't offer cheap kits for electric auto conversion ?
In fact they don't offer any kits.
How do you think: for the sake of low demand ?

That's an interesting way of looking at marketing and you're certainly entitled to your conspiracy theorist opinions, but you didn't post a link to the cheap efficient solution that I can buy 1000 pieces of right now.

 

[eP]

Extra weight may not be important for you, but you asked for my opinion. Absolute weight is important to me.

Also, the idea of switching between 2 configurations of motor seems, well, rather intellectually squalid -

Switching between MULTIPLE configurations of gears seems more squalid i see
And keep in mind in my idea i need soft electrical switching, and you want hard mechanical switching.

It is a big difference, as you lose a lot when you switch gears at full load.

that's rather an ethereal reason, though... If it was a series-parallel set-up, I might warm to the idea.

2 motors = 2 things to go wrong. (and almost dual redundancy, it's true .

So you want worse redundancy as you want use only one gear at a time

It is true. 8)

One motor has to go in the front fork. I agree with Lowell, on this. I wouldn't risk it for myself...

Hub motors = less effective suspension.

Keep in mind my idea of cheap 2 motors conf is for unsuspended bikes first of all.
So unsuspended mass is no problem at that case. 8)

 

[eP]

That's an interesting way of looking at marketing and you're certainly entitled to your conspiracy theorist opinions, but you didn't post a link to the cheap efficient solution that I can buy 1000 pieces of right now.

Why i didn't post it - how do you think ?

RC market is much more wider/mature so it is not to hard find cheap efficient solutions at almost each category at that market.

 

[Miles]

So you want worse redundancy as you want use only one gear at a time

No,no,no.... the dual-rendundancy was a positive concession.... If one motor fails, you still have the other - even if its function is not ideal.

 

[Miles]

Keep in mind my idea of cheap 2 motors conf is for unsuspended bikes first of all.
So unsuspended mass is no problem at that case.

It's still mass in the worst possible place for it...... (well, maybe you could find a more worse place, from the point of view of handling...)

 

[Lowell]

http://www.walmart.com/catalog/product.do?product_id=2513008

$80 for an aluminum framed FS bike. Obviously won't be great, but shows just how cheap bikes can be made these days. I've also seen low end suspension forks in the used bins for $10-$20 and bike shops and sports stores.
If you're $10 short, there's always the steel version:
http://www.walmart.com/catalog/product.do?product_id=4231518

 

[eP]

http://www.walmart.com/catalog/product.do?product_id=2513008

$80 for an aluminum framed FS bike. Obviously won't be great, but shows just how cheap bikes can be made these days. I've also seen low end suspension forks in the used bins for $10-$20 and bike shops and sports stores.
If you're $10 short, there's always the steel version:
http://www.walmart.com/catalog/product.do?product_id=4231518

I've bought my used cro-mo framed bike for around $45 (including delivery), so $20 for fork alone it is still a lot of money :wink:

You have to keep in mind my 2 motors idea is not a high end solution, so the front motor is not obligatory and heavy.

It is individual decision if suspention is needed or how much heavy front hub should be.
But the idea is still the same - no multiple gears for motors and two chains drive at rear wheel.

 

[eP]

Keep in mind my idea of cheap 2 motors conf is for unsuspended bikes first of all.
So unsuspended mass is no problem at that case.

It's still mass in the worst possible place for it...... (well, maybe you could find a more worse place, from the point of view of handling...)

Yes i can find i'm sure - above my head.
More mass at the hub level - lower center of gravity so i don't think it is so badly place for extra mass.

 

[Miles]

More mass at the hub level - lower center of gravity so i don't think it is so badly place for extra mass.

Not so good for potholes or bumps.... Maybe the roads in Poland are better than UK?

 

[eP]

More mass at the hub level - lower center of gravity so i don't think it is so badly place for extra mass.

Not so good for potholes or bumps.... Maybe the roads in Poland are better than UK?

Our roads aren't better thnak UK i'm sure, but until i mostly biking less than 20 mph i'm still live ( over 1650 miles on my counter so far ) at completely unsuspended bike.

I have to admit again: 2 motor conf. idea is not for high end solution or for record breaking. So discussing minor obstacles is simply futile at this case.

Do you looking for moderate powerful and flexible low-end bike or extreme powerful and light high-end bike ?
And how much you are ready to spend for your ideal e-bike ?

 

[Miles]

Do you looking for moderate powerful and flexible low-end bike or extreme powerful and light high-end bike ?
And how much you are ready to spend for your ideal e-bike ?

Neither, really.

Moderate power, lightweight, high quality bike.

Power-assist to be used mainly for hills. For urban use, so high speed isn't a priority.

As few compromises to its performance as a normal bike as possible.

Quiet - I don't want something like the Cyclone, that sounds like a milk-float...

There's nothing available to suit me, so I'm building my own. It will be similar to Randy's set-up - 2 chains (or 1 chain, 1belt) converging on an internal geared hub.

 

[EbikeMaui]

Do you looking for moderate powerful and flexible low-end bike or extreme powerful and light high-end bike ?
And how much you are ready to spend for your ideal e-bike ?

Neither, really.

Moderate power, lightweight, high quality bike.

Power-assist to be used mainly for hills. For urban use, so high speed isn't a priority.

As few compromises to its performance as a normal bike as possible.

Quiet - I don't want something like the Cyclone, that sounds like a milk-float...

There's nothing available to suit me, so I'm building my own. It will be similar to Randy's set-up - 2 chains (or 1 chain, 1belt) converging on an internal geared hub.

Sooner or later you guys will figure out My designs and components I have shown hard to beat in costs and reliability.Efficiency is also a BIG perk.I like the Idea of a making a 7 lb 1 inch thick Disc Motor that slides onto a freehub. No spoke job is required and the hub motor can be removed or installed in 5 minutes.Like changing a slide on cassette and connecting a couple wire plugs.No Chain involved ! unless you want a pedal chain to stay in this forum. :lol:

 

[EbikeMaui]

More mass at the hub level - lower center of gravity so i don't think it is so badly place for extra mass.

Not so good for potholes or bumps.... Maybe the roads in Poland are better than UK?

Our roads aren't better thnak UK i'm sure, but until i mostly biking less than 20 mph i'm still live ( over 1650 miles on my counter so far ) at completely unsuspended bike.

I have to admit again: 2 motor conf. idea is not for high end solution or for record breaking. So discussing minor obstacles is simply futile at this case.

Do you looking for moderate powerful and flexible low-end bike or extreme powerful and light high-end bike ?
And how much you are ready to spend for your ideal e-bike ?

How many Polocks does it take to climb a Volcano ? ....

 

[eP]

How many Polocks does it take to climb a Volcano ? ....

Poles, Randy Poles.

Poles are everywhere now.
Ask Miles: how many Poles are in London ? :wink:

So some of us taking to climb a Volcano i'm sure 8)

Miles

Power-assist to be used mainly for hills. For urban use, so high speed isn't a priority.

As few compromises to its performance as a normal bike as possible.

So why you so take care about suspention if you don't care about speed and yours roads are in well condiction ?

My 2 motors cofig idea is first off all for the beginers. The second motor (front hub) is not obligatory especially if you dont care about speed.

The idea is to mount cheap one gear freewheel at opposite side of the rear hub (for second chain). So this way you can save the money for the front hub if the speed is not enough for you or the 2'nd chain is to noisy at flat road.

If you spend the money for the geared hub (over $100) this way you limit your possible spending for silence front hub motor and you have to ride at noisy rear motor all the time.
As a negative bonus you have to switching gears of course.

 

[Toorbough ULL-Zeveigh]

How many Polocks does it take to climb a Volcano ? ....

I thought you said your motor was built with 12 poles?

 

[eP]

How many Polocks does it take to climb a Volcano ? ....

I thought you said your motor was built with 12 poles?

More poles - the stronger motor is :wink:

 

[EbikeMaui]

How many Polocks does it take to climb a Volcano ? ....

I thought you said your motor was built with 12 poles?

More poles - the stronger motor is :wink:

Take the fan off and count them X 8 to 1 quiet chain reduction.. takes less magnet material than a Hub motor with the same wheel rpm and torque range.

 

[EbikeMaui]

More mass at the hub level - lower center of gravity so i don't think it is so badly place for extra mass.

Not so good for potholes or bumps.... Maybe the roads in Poland are better than UK?

Our roads aren't better thnak UK i'm sure, but until i mostly biking less than 20 mph i'm still live ( over 1650 miles on my counter so far ) at completely unsuspended bike.

I have to admit again: 2 motor conf. idea is not for high end solution or for record breaking. So discussing minor obstacles is simply futile at this case.

Do you looking for moderate powerful and flexible low-end bike or extreme powerful and light high-end bike ?
And how much you are ready to spend for your ideal e-bike ?

How many Polocks does it take to climb a Volcano ? ....

The answer is !/4 polish is all it took.

 

[Miles]

So why you so take care about suspention if you don't care about speed and yours roads are in well condiction ?

My 2 motors cofig idea is first off all for the beginers. The second motor (front hub) is not obligatory especially if you dont care about speed.

The idea is to mount cheap one gear freewheel at opposite side of the rear hub (for second chain). So this way you can save the money for the front hub if the speed is not enough for you or the 2'nd chain is to noisy at flat road.

If you spend the money for the geared hub (over $100) this way you limit your possible spending for silence front hub motor and you have to ride at noisy rear motor all the time.
As a negative bonus you have to switching gears of course.

The roads are not in good condition, at all.... that was my point - also I'm planning to use 406 wheels, so suspension is necessary.

A single hub motor, unless it's oversized, is not enough.....

I'm not going to have a noisy set-up - if I end up using a Gates Polychain, that's not a problem, for me.

I really don't see why you're making such an issue out of changing gears. I need gears to optimise my cadence, anyway... There are only 3 gears on the Dual-Drive and most of the time I'll be in 2nd, which is direct drive, for efficiency.

For the present legislation in EU, a hub motor is not the way to go, IMO.

2 Hub motors would do it, but it's not the solution for me.

If I'm going to the trouble of mounting a motor out of the wheel, I would put it through the gear train.

If you want to try 2 cheap hub motors, or a hub motor plus a Currie set-up, fine, but you haven't persuaded me of the merits....

 

[Miles]

More poles - the stronger motor is :wink:

 

[EbikeMaui]

More poles - the stronger motor is :wink:

There is not a need for more than 12 poles on a bike motor unless it is a direct drive hub motor that would have much weaker magnets.
A 3/4" stator 12" in dia using 36 poles with 1/3 of the size magnets as the 12 pole motor pictured = MORE TORQUE at any rpm with a lighter rotor and cleaner flux paths for both the rotor and stator eliminating some ripple current and alowing a larger core saturation point. All at less costs and weight at a better efficiency.

 

[eP]

More poles - the stronger motor is :wink:

There is not a need for more than 12 poles on a bike motor unless it is a direct drive hub motor that would have much weaker magnets.

You have simply no idea how strong magnets should be for direct drive hub.

You have no idea what efficiency is and where coming from. (Yours : "max. eff." at stall point )

A 3/4" stator 12" in dia using 36 poles with 1/3 of the size magnets as the 12 pole motor pictured = MORE TORQUE at any rpm with a lighter rotor and cleaner flux paths for both the rotor and stator eliminating some ripple current and alowing a larger core saturation point. All at less costs and weight at a better efficiency.

So stop telling us yours bla bla bla and show us yours results.
Your heavy, low pole, high speed motor with weak magnets have no more than 80% efficiency.
And yours efficiency is much worse at light loads as yours rpms are high and you must use gears all the time.

 

[EbikeMaui]

If you think so use YOUR solution.