New here: Electric bicycle question

johns said:

I'm reading everything I can find on bicycles with electric motors.
I've come to the conclusion that 99% of what is being done is
not great.

(...)

The best batteries for these things are Lithium Ion.
They are powerful and very light weight.
http://www.greenspeed.us/bionx_350_lithium_battery.htm
They have a high 'self discharge' rate though, so plan on
charging before and after every ride, not every 3 weeks.

Please incorporate an overrunning clutch in your design so
that you don't have to peddle against the magnets in your
hub motor. The workaround is to put the motor in constant
'assist' mode to compensate for magnetic drag.
This isn't what you had in mind, based on your post.
The continuous drag is not worth the potential for
'regenerative braking' IMHO.

You will wish you had a throttle in short order,
I predict. 🙂
An electric motor boosts a bikes 'fun index', especially
when you engage the throttle. BTDT and got the silly grin.

The thick rear mounted hub motor can turn the chain line into
a nightmare, so I approve of your front - mounted option.
You are doubtlessly aware of how a front-mounted motor
will affect the handling of your bike.....

I really like my Bionx equipped Montague; It now has seven
speeds instead of 24 and it now back-pedals safely.

Please consider the kits on the market carefully while you
think about the cost of your time. For example, I decided
that there was no way that I could develop a system nearly
as good as the Bionx for less money than just buying it
installed. This design job is a very deep puddle indeed.

--Winston

johns said:

- They add too much weight, and so the bike is not a hybrid.

The gross vehicle weight is comparable whether the assist unit is
heavy or light. Are you suggesting that you can pedal a bike/rider
combo weighing (for instance) 250 pounds, but not one weighing 280
pounds? A heavier assist unit can offer more range, torque, and/or
speed. Lighter is better, but only if the assist does what you want
it to do.

Quoted message said:

- Almost none of them seem to understand what is really
meant by pedal-assist.

How much the rider pedals is a matter of taste. Some systems, like
Stokemonkey, can't operate at all unless the rider is pedaling.

Quoted message said:

What I want to build is this:

- I don't want to add more than 12 pounds to the bike.

Good luck with that. If you are adding a motor and energy source that
contribute (presumably) about 5% to the bike's gross weight, you
should expect performance in accordance with that figure.

Quoted message said:

- So, I think I want a front wheel hub motor that is very
light weight .. 5 - 6 pounds tops.

....

Quoted message said:

Do any of you have experience
with this, and know of a good quality kit for a reasonable
cost ?

I can't speak for its quality or durability, but this kit meets your
general specs:

http://nano-motor.co.uk/nanomotor.php

Chalo

johns said:

I'm reading everything I can find on bicycles with electric motors.

Quoted message said:

What I want to build is this:

- I don't want to add more than 12 pounds to the bike.

- I don't want to increase unsprung weight, but at the same
time, I don't want a really complicated setup trying to
prevent that.

Why suspend the bike at all? Or if you use a front wheel drive, then
suspend the rear only or visa versa. I recently rode a cruiser bike with
a suspended seatpost and was amazed at how well it worked. The bicycle
itself had no suspension but the ride was overall (from a cruiser view)
as good as a suspended bike.

I'm skeptical that there is much of a market for these. A < 51 cc
scooter is treated like a bicycle where I am. They go on bicycle trails.
No insurance or registration or license to ride one. Comfortable, good
storage, reasonable weather protection & a good deal more convenient to
use due to the ease of recharging.

johns said:

I'm reading everything I can find on bicycles with electric motors.
I've come to the conclusion that 99% of what is being done is
not great. A lot of it is just tinkering without actually seeing the
"niche" that an e-bike could fill best. I want to build one, but I
want it to work ... not be an unsafe toy. So far here's what I
see:
.....

johns

The BionX kits are pretty nice for what they do, for my taste they just
don't do it -long- enough.

I noticed when skimming message boards, that most people with electrics
ended up wanting better/longer-lasting batteries. They never got to ride
as long as they wished they could.

Also--concerning both gas and electric setups--none really mount to a
normal bicycle conveniently. The easiest kits to mount would be the
electric front-hubs, because these can be fit on just about ANY
large-wheel bicycle. Most of the others however are a cluster-fudge.
You'd need a custom frame to have them install easily and work well
(where the engine or batteries don't take up any of your cargo space or
require you to use any odd bicycle parts like xtra-wide cranks, for
example).

There's an early Honda motorized bicycle picture online somewhere,
showing a gas engine mounted near the head tube in the front triangle of
a frame, with a long chain running back to the rear wheel. This is not a
perfect solution but I think it comes pretty close in terms of hanging a
gas engine on a regular (upright) bicycle frame that wasn't meant for
one. No company now produces a kit anything like this however.
------
I ended up getting a gas engine (Golden Eagle) that goes about 32 miles
on one tank, or about 200 miles per gallon. With a 2-gallon gas can
strapped to the bike I can get on it in the morning, and wander around
the countryside all damn day and still not run out of gas by late
afternoon.

Of course I don't get much exercise but that's not what it was for;
getting places without getting sweaty was what it was for. And I can't
pedal any of my bikes 30 mph for very long at all, much less can I do it
without sweating.
~

Quoted message said:

johns said:

I'm reading everything I can find on bicycles with electric motors.
I've come to the conclusion that 99% of what is being done is
not great. A lot of it is just tinkering without actually seeing the
"niche" that an e-bike could fill best. I want to build one, but I
want it to work ... not be an unsafe toy. So far here's what I
see:

DougC said:

The BionX kits are pretty nice for what they do, for my taste they just
don't do it -long- enough.

I noticed when skimming message boards, that most people with electrics
ended up wanting better/longer-lasting batteries. They never got to ride
as long as they wished they could.

Also--concerning both gas and electric setups--none really mount to a
normal bicycle conveniently. The easiest kits to mount would be the
electric front-hubs, because these can be fit on just about ANY
large-wheel bicycle. Most of the others however are a cluster-fudge.
You'd need a custom frame to have them install easily and work well
(where the engine or batteries don't take up any of your cargo space or
require you to use any odd bicycle parts like xtra-wide cranks, for
example).

There's an early Honda motorized bicycle picture online somewhere,
showing a gas engine mounted near the head tube in the front triangle of
a frame, with a long chain running back to the rear wheel. This is not a
perfect solution but I think it comes pretty close in terms of hanging a
gas engine on a regular (upright) bicycle frame that wasn't meant for
one. No company now produces a kit anything like this however.
------
I ended up getting a gas engine (Golden Eagle) that goes about 32 miles
on one tank, or about 200 miles per gallon. With a 2-gallon gas can
strapped to the bike I can get on it in the morning, and wander around
the countryside all damn day and still not run out of gas by late
afternoon.

Of course I don't get much exercise but that's not what it was for;
getting places without getting sweaty was what it was for. And I can't
pedal any of my bikes 30 mph for very long at all, much less can I do it
without sweating.

Here's your photo:
http://www.thisoldhonda.org/articles_detail.php?ID=5

For people who like this sort of thing, this is the sort of thing they
like. Probably an acquired taste.
--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971
** Posted from http://www.teranews.com **

DougC said:

johns said:

I'm reading everything I can find on bicycles with electric motors.
I've come to the conclusion that 99% of what is being done is
not great. A lot of it is just tinkering without actually seeing the
"niche" that an e-bike could fill best. I want to build one, but I
want it to work ... not be an unsafe toy. So far here's what I
see:
.....

Quoted message said:

johns

The BionX kits are pretty nice for what they do, for my taste they just
don't do it -long- enough.

I noticed when skimming message boards, that most people with electrics
ended up wanting better/longer-lasting batteries. They never got to ride
as long as they wished they could.

Feller who stopped me in the street to admire one of my comfort bikes
said he had one of the Giant electric bikes and the speed was limited
(probably because in the UK, where the local importer gets Giant
bikes, over 15mph is a legal top limit beyond which the thing becomes
a motor cycle with all kinds of expensive laws relating...) and the
range was 10-12 miles. He felt hard done by because he expected more.
I wondered if he had any experience with rechargeable batteries. I'm a
professional skeptic, but even I think that some vendors' claims for
rechargeable battery work periods are breathtaking.

Quoted message said:

Also--concerning both gas and electric setups--none really mount to a
normal bicycle conveniently. The easiest kits to mount would be the
electric front-hubs, because these can be fit on just about ANY
large-wheel bicycle. Most of the others however are a cluster-fudge.
You'd need a custom frame to have them install easily and work well
(where the engine or batteries don't take up any of your cargo space or
require you to use any odd bicycle parts like xtra-wide cranks, for
example).

Someone gave a URL to not one but two makes of bikes with the battery
in the front wheel. What sort of incompetents willfully add weight to
the wheels when there is somewhere else (the rack, the inside of the
tubes, a longer wheelbase with the batteries behind the seat tube,
etc, etc, etc,) to add heavy batteries?

Quoted message said:

There's an early Honda motorized bicycle picture online somewhere,
showing a gas engine mounted near the head tube in the front triangle of
a frame, with a long chain running back to the rear wheel. This is not a
perfect solution but I think it comes pretty close in terms of hanging a
gas engine on a regular (upright) bicycle frame that wasn't meant for
one. No company now produces a kit anything like this however.
  ------
I ended up getting a gas engine (Golden Eagle) that goes about 32 miles
on one tank, or about 200 miles per gallon. With a 2-gallon gas can
strapped to the bike I can get on it in the morning, and wander around
the countryside all damn day and still not run out of gas by late
afternoon.

There used to be, when I was a boy in the later 1950s, a little snot
separator petrol engine that was somehow attached to the bike, perhaps
on a hinge from the bandlebars, perhaps directly to the axle on
stalks, which was started by moving a lever which lowered a roller
onto the front wheel. The same roller would provide drive, presumably
not very efficiently in the wet. The assembly was probably Italian.
The person who had it gave up on it after not too long and bought a
used Fiat Topolino instead. I remember it because later I had that
particlar Topolino, and fitted a Chevy mouse motor on rails under it,
a nice big wolf in little lamb's clothing that won a lot of drag races
up the local mountains.

It was about this time that another little snot separator, the Honda
50cc bike that kids could ride without a motorcycle license and,
better still, get insurance for, killed what little bicycling was left
where I lived.

Quoted message said:

Of course I don't get much exercise but that's not what it was for;
getting places without getting sweaty was what it was for. And I can't
pedal any of my bikes 30 mph for very long at all, much less can I do it
without sweating.
~

For me the point of cycling is raise my metabolic rate quickly in a
more enjoyable manner, and in more intelligent company than the
muscleheads and grim yuppies in the gyms. I don't care who knows that
I perspire.

Andre Jute
http://members.lycos.co.uk/fiultra/BICYCLE%20%26%20CYCLING.html