Any success with add on electric motors to Conventional Bikes?

I ask because I saw two different bikes (with what looked like two
different motors) in one day. Kind of surprising to see two in about
an hour's span.

Seems a good design might place a small motor behind the seat pole
near the back brake area w/ some batteries slim packed into the
triangle above the pedal cranks; keeps it low and if slim enough the
only side affect other than over all weight might be sail effect from
cross winds.


TBerk

On Apr 26, 11:38 am, TBerk wrote:
I ask because I saw two different bikes (with what looked like two
different motors) in one day. Kind of surprising to see two in about
an hour's span.

Seems a good design might place a small motor behind the seat pole
near the back brake area w/ some batteries slim packed into the
triangle above the pedal cranks; keeps it low and if slim enough the
only side affect other than over all weight might be sail effect from
cross winds.

I've never done it myself, but the only truly successful electric add-
ons to conventional bikes I've seen and heard about have been hub
motors, where you basically swap in a new wheel. A bit pricier than a
"Solex" type friction drive, I expect, but they don't chew up your
tires. And the wattages they're available at mean real acceleration
and hill climbing.

Brian Huntley wrote:
On Apr 26, 11:38 am, TBerk wrote:

I ask because I saw two different bikes (with what looked like two
different motors) in one day. Kind of surprising to see two in about
an hour's span.

Seems a good design might place a small motor behind the seat pole
near the back brake area w/ some batteries slim packed into the
triangle above the pedal cranks; keeps it low and if slim enough the
only side affect other than over all weight might be sail effect from
cross winds.


I've never done it myself, but the only truly successful electric add-
ons to conventional bikes I've seen and heard about have been hub
motors, where you basically swap in a new wheel. A bit pricier than a
"Solex" type friction drive, I expect, but they don't chew up your
tires. And the wattages they're available at mean real acceleration
and hill climbing.

That would be a GREAT application for some hybrid-car-esque software and
regen braking...

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

Nate Nagel wrote:

Brian Huntley wrote:

I've never done it myself, but the only truly successful electric add-
ons to conventional bikes I've seen and heard about have been hub
motors, where you basically swap in a new wheel.

That would be a GREAT application for some hybrid-car-esque software and
regen braking...

Some of them are direct drive with high pole count armatures, and
regen makes some sense for those. Geared hub motors use one-way
clutches, just like we do on our pedal drivetrains-- because for a
bike, the ability to coast freely does a lot more for you than the
ability to recapture braking energy.

Chalo

TBerk wrote:

I ask because I saw two different bikes (with what looked like two
different motors) in one day. Kind of surprising to see two in about
an hour's span.

http://crystalyte.com/
http://bionx.ca/
http://www.cyclone-usa.com/
http://www.izipusa.com/
http://goldenmotor.com/

http://ebikes.ca/
http://electricrider.com/

http://endless-sphere.com/forums/viewforum.php?f=3
http://groups.yahoo.com/group/e-motor-assist/
http://groups.yahoo.com/group/power-assist/

Seems a good design might place a small motor behind the seat pole
near the back brake area w/ some batteries slim packed into the
triangle above the pedal cranks;

There's not all that much room there, and potential chain lines to a
rear wheel sprocket are likely to foul the frame. I ride a 27"
frame-- just about the largest factory-made size-- and I was unable to
fit a motor with reduction chain drive there when I built my first e-
bike. I eventually mounted the motor just under the bike's downtube,
with the chain running above and below the left side of the bottom
bracket spindle.

Stokemonkey mounts where you suggest, but it drives the crank, and it
only fits an Xtracycle-equipped bike:

http://cleverchimp.com/products/stokemonkey/

Chalo

TBerk wrote:

I ask because I saw two different bikes (with what looked like two
different motors) in one day. Kind of surprising to see two in about
an hour's span.

http://crystalyte.com/
http://bionx.ca/
http://www.cyclone-usa.com/
http://www.izipusa.com/
http://goldenmotor.com/

http://ebikes.ca/
http://electricrider.com/

http://endless-sphere.com/forums/viewforum.php?f=3
http://groups.yahoo.com/group/e-motor-assist/
http://groups.yahoo.com/group/power-assist/

Seems a good design might place a small motor behind the seat pole
near the back brake area w/ some batteries slim packed into the
triangle above the pedal cranks;

There's not all that much room there, and potential chain lines to a
rear wheel sprocket are likely to foul the frame. I ride a 27"
frame-- just about the largest factory-made size-- and I was unable to
fit a motor with reduction chain drive there when I built my first e-
bike. I eventually mounted the motor just under the bike's downtube,
with the chain running above and below the left side of the bottom
bracket spindle.

Stokemonkey mounts where you suggest, but it drives the crank, and it
only fits an Xtracycle-equipped bike:

http://cleverchimp.com/products/stokemonkey/

Chalo

In article
,
Chalo wrote:

TBerk wrote:

I ask because I saw two different bikes (with what looked like two
different motors) in one day. Kind of surprising to see two in about
an hour's span.

Seems a good design might place a small motor behind the seat pole
near the back brake area w/ some batteries slim packed into the
triangle above the pedal cranks;

There's not all that much room there, and potential chain lines to a
rear wheel sprocket are likely to foul the frame. I ride a 27"
frame-- just about the largest factory-made size-- and I was unable to
fit a motor with reduction chain drive there when I built my first e-
bike. I eventually mounted the motor just under the bike's downtube,
with the chain running above and below the left side of the bottom
bracket spindle.

I saw a homebrew with a clever-looking mount: heavy-duty custom rack
carrying an electric motor directly above the rear wheel. Chain drive
from the motor down to the non-drive side of the hub, where there was a
second freewheel for the motor drive.

I believe the rider was using a LHD BMX cog on the hub, and I assume
(with no certainty) he was using some flavor of flip-flop hub.

--
Ryan Cousineau http://www.wiredcola.com/
"In other newsgroups, they killfile trolls."
"In rec.bicycles.racing, we coach them."

Ryan Cousineau wrote:
...
I saw a homebrew with a clever-looking mount: heavy-duty custom rack
carrying an electric motor directly above the rear wheel. Chain drive
from the motor down to the non-drive side of the hub, where there was a
second freewheel for the motor drive.

I believe the rider was using a LHD BMX cog on the hub, and I assume
(with no certainty) he was using some flavor of flip-flop hub.


Did it really have freewheels on BOTH sides? Or just sprockets on both
sides?... A number of kits use a chain drive on the left side, but the
sprocket on the wheel is just bolted on, literally through the spokes.
The engine drive side normally just spins all the time.

There are people who use a disk brake hub, and bolt a sprocket to the
disk mount. Also at least one company has made a double-drive hub, with
the normal freewheel on the right and a bolted-on "stationary" sprocket
on the left (Staton kits have these).

Motorized-bike people have been wishing for a double-freewheel hub for a
/long/ time, and I'd not heard of any in production. There are flip-flop
BMX hubs that can take freewheels on both sides but I was informed
(here, quite possibly) that the threading is the same direction on both
sides--so the left side can't be used for driving, unless it's flipped
over to the right.
~

TBerk Wrote:
I ask because I saw two different bikes (with what looked like two
different motors) in one day. Kind of surprising to see two in about
an hour's span.

Seems a good design might place a small motor behind the seat pole
near the back brake area w/ some batteries slim packed into the
triangle above the pedal cranks; keeps it low and if slim enough the
only side affect other than over all weight might be sail effect from
cross winds.


TBerk
The easiest conversion is a front hub motor. I installed this one, a
Wilderness Energy 450 watt brushless in my wife's bike.
http://i32.tinypic.com/359b7eu.jpg
It worked well. lots of power and range, but I did not care for how it
affected the handling of the bike. The weight of the hub seemed to cause
a lot of flexing in the fork,and made what had been a nice,light
handling bike in to a clumsy tank.
I improved it somewhat by swapping in a cheapo suspension fork.
http://tinypic.com/view.php?pic=2cr2jb9&s=3
I was concerned about the ability of the fork dropouts to withstand
the torque of the axle over the long term, so I fabricated these tabs to
re-enforce them.
http://i28.tinypic.com/x55he9.jpg
It complicates wheel removal,of course, but it's worth it for a bit of
peace of mind.
All in all, it has worked well for the two years she has been using
it, the only problem arising from moisture permeating the controller. A
good dose of WD40
looked after that.
I know it's not the best system out there, but it's ok for the price.
Dan Burkhart
www.boomerbicycle.ca


--
Dan Burkhart

In article ,
DougC wrote:

Ryan Cousineau wrote:
...
I saw a homebrew with a clever-looking mount: heavy-duty custom rack
carrying an electric motor directly above the rear wheel. Chain drive
from the motor down to the non-drive side of the hub, where there was a
second freewheel for the motor drive.

I believe the rider was using a LHD BMX cog on the hub, and I assume
(with no certainty) he was using some flavor of flip-flop hub.


Did it really have freewheels on BOTH sides? Or just sprockets on both
sides?... A number of kits use a chain drive on the left side, but the
sprocket on the wheel is just bolted on, literally through the spokes.
The engine drive side normally just spins all the time.

I dug up my photos to review the evidence. It's definitely a LHD
freewheel. Indeed, the drive side uses a multi-speed freewheel.

http://www.flickr.com/photos/rcousine/2448067142/

There are people who use a disk brake hub, and bolt a sprocket to the
disk mount. Also at least one company has made a double-drive hub, with
the normal freewheel on the right and a bolted-on "stationary" sprocket
on the left (Staton kits have these).

Motorized-bike people have been wishing for a double-freewheel hub for a
/long/ time, and I'd not heard of any in production. There are flip-flop
BMX hubs that can take freewheels on both sides but I was informed
(here, quite possibly) that the threading is the same direction on both
sides--so the left side can't be used for driving, unless it's flipped
over to the right.

Motorized bike people need to pay more attention to obscure BMX parts,
where the Left-Hand Drive exists:

https://www.jrbicycles.com/storefron...od&productId=6
54

The purpose of these off-side drives, aside from looking cool, is to let
riders who prefer to do coping grinds on the right-hand side to do so
unimpeded.

--
Ryan Cousineau http://www.wiredcola.com/
"In other newsgroups, they killfile trolls."
"In rec.bicycles.racing, we coach them."