integrated crank drive system: optibike ripoff?

[wingtip]

i just noticed this crank drive system being marketed on bmsbattery while i was contemplating ordering one of their inexpensive li-ion packs.


http://www.bmsbattery.com/central-motor/321-ebike-central-motor.html


looks like it's loosely based on the optibike drive system. Hmmm, I wonder if their patents are expiring or something....

 

[neptronix]

Should work great on all those ebikes that have 100-150mm dia. bottom brackets. :lol:

 

[DAND214]

patents are expiring or something....

Do they know what a patent is, in China?
Dan

 

[Whiplash]

Huh, any idea on power handling ability??

 

[SamTexas]

Very interesting. Has anyone here tried it? Is there more info available?

 

[Hillhater]

Huh, any idea on power handling ability??

The rating is 200w ( 36v , 6A) at 135 rpm.
Being a crank drive there is not a lot of over volting potential ( crank speed ?) so any power boost would have to come from increased current. 20 A should get 600W but who knows how much heat ?
Obviously need a special frame to use as a crank motor, but its low speed could make it a useful mid mount drive motor ?

 

[Miles]

patents are expiring or something....

Do they know what a patent is, in China?
Dan

They certainly do. They have more ebike related patents than any other country.....

The Optibike patent doesn't expire till 2021.

 

[Whiplash]

Huh, any idea on power handling ability??

The rating is 200w ( 36v , 6A) at 135 rpm.
Being a crank drive there is not a lot of over volting potential ( crank speed ?) so any power boost would have to come from increased current. 20 A should get 600W but who knows how much heat ?
Obviously need a special frame to use as a crank motor, but its low speed could make it a useful mid mount drive motor ?

Hmm, I bet if it would take that much with standard wiring, it could be beefed up to take even more. If you can get up around 1000W with a mid drive, that will perform really pretty well! At 160.00 it seems like something I might like to try..

Are there any other pics to see how its mounted??

 

[TylerDurden]

i just noticed this crank drive system being marketed on bmsbattery while i was contemplating ordering one of their inexpensive li-ion packs.
http://www.bmsbattery.com/central-motor/321-ebike-central-motor.html

I can't get their site to load.

 

[Hillhater]

Are there any other pics to see how its mounted??

The drg/diagram shows the 3 big ( 8mm dia & 54mm wide) mounting bolt locations..on the left

 

[TylerDurden]

Ah... finally got in.

Not much info. Be nice to know specs and reduction type (assuming).

Might make a good 1:1 chainwheel driver.

 

[Miles]

Not much info. Be nice to know specs and reduction type (assuming).

Weight 3.9Kg
Rated Torque 12.7±10%N.m
Rated Speed 135±10%Rpm
Rated Current ≤6.4A
Power 200Watts
Phase Angle 120°
Normal Voltage 36V
No-Load Speed 155±10%Rpm
No-Load Current ≤0.8A
Hall Sensor Yes
Efficiency ≥78%

Deja vu:
http://endless-sphere.com/forums/viewtopic.php?f=28&t=26995

 

[TylerDurden]

Deja vu:
http://endless-sphere.com/forums/viewtopic.php?f=28&t=26995

Thanks Miles, I missed that one.

 

[zap]

Here's what appears to be a similar unit on a folder on ebay:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330583342031+&clk_rvr_id=247424258171

 

[SamTexas]

Here's what appears to be a similar unit on a folder on ebay:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330583342031+&clk_rvr_id=247424258171

Excerpt from the above EBay listing:

After years of testing most of the electric bikes and electric bike kits, we believe that this is thebest designed bike in the world for cursing around the city.

I want one!