My KZ750 electric motorcycle project.
Edit: 5/12/07 updated specs
Edit: 3/30/08 Removing circuit breaker. It is not a reliable disconnect. Instead I'll use the SW200 contactor as the emergency disconnect, and have the clutch cable run to a switch that is in the circuit powering the SW200 contactor coil.
First two pics were recovered by archive team, thanks!
Was going to wait till I had it done, but they made me jump to gun and take a few more pics of the bike as it is now. Now I got to hustle and get this sucker rolling!
Old pic, I think about a year ago. Note messy 12v wiring still hanging from frame *shudder*.

![]()
Pic from Nov. 2, 2006.

![]()
Following pics were taken today.

Click here for full size view
![]()

Click here for full size view
![]()

Click here for full size view
![]()
Bike specs:
(2) Eteks being run in parallel at 72v
(6) EVP35-12 B&B batteries
Zivan NG1 Charger
(5) Powercheq battery regulators
Curtis 72v 400a controller
Curtis Albright Contactor SW200-505
Airpax Circuit Breaker trip amps: 313 NOTE: Removed!
"Fibergrate Dynaform" fiberglass material used for battery mounts, available from http://www.usplastic.com Used fiberglass repair to form material around bottom of cradle to secure it.
72T Rear sprocket from http://www.surpluscenter.com
11T Drive sprocket (not pictured)
Aluminum shaft for coupling (not pictured)
#40 Chain (not pictured)
UPDATE:
LogiSystems 48-72v 1140 amp controller
Custom made chain tensioner
Performance w/400A Curtis & 12T sprocket:
0-30 mph 2.5 sec
0-55 mph 6 sec
Controller max current: 550+ amps
---
Avatar taken from http://www.electricmotorbike.org/
Anyone got one they might want to sell?
that is great. Wish I would have thought of that. I look forward to seeing how it works out, if the motors work well there or get in the way. Where is it located? I'll have to try it when it is done :)
Are you moving the footpegs forward since the motors are gonna be in the way of your legs? Or is it possible to recess the motors further in? Are you also gonna use some sort of insulated barrier to separate the cables and connectors for the etek so that you dont accidently rub them with your legs?
Looking good so far Andrew. What's your projected weight and range? I see you've got an Airpax circuit breaker. Where will you install that – I can't see it in the photos. The reason I ask is that I've just bought one for my own motorcycle conversion, but it says that it has to be installed vertically – any idea why?
That's going to be a monster with twin motors. Looks great.
I'd highly recommend making some "crash bars" to protect the motor brush caps in the likely event that someday the cycle tips over. Even a simple peg that sticks out to hit the pavement first will help save them.
I'll be interested to see how your coulpling between motors works.
`Andrew,
No problem, glad to see we were able to help. It's just one very small step in retrieving some of the old Voltage Forum lost Archives from being lost forever. We'll be watching your progress.
Archive Team ;)
archive_team@visforvoltage-moderator.net
Voltage Forum Archives
http://visforvoltage.org/forum/230
1000's of lost images from the old Voltage Forum looking for there owners.
dude, totally send me an email, i did not hope to find another electric motorcycle project in rio rancho
hendersonmotorcycles@yahoo.com
http://geocities.com/hendersonmotorcycles/blog.html
http://www.austinev.org/evalbum/1000
http://geocities.com/solarcookingman
Andrew, nice work. looks awesome. How many months did that take you?
I'm just starting a similar project running two eteks at 72volts in an r6 frame. I have a question for you. How are you running the eteks to the rear wheel. I'm trying to run mine through a jack shaft, but have yet to find a suitable one. I think I need something a little bulkier than the go-cart drop-ins that i keep finding. Any advice would be appreciated.
thanks,
M
Thanks for the close-up Andrew. That's exactly the same way I planned to fit my breaker – using the clutch cable to activate it. I'll do a little more searching myself and see if I can find out why a breaker should be installed vertically ...
... I just found this:
"Many hydraulic-magnetic breakers are available with a selection of delay curves to fit particular applications. Hydraulic-magnetic circuit breakers are not affected by ambient temperature, but tend to be sensitive to rotational position. These breakers should be mounted in a vertical position to prevent gravity from influencing the movement of the solenoid. If mounted in a different position, derating may be required."
So it's not really a problem if we're just using them as on/off switches.
`hendersonmotorcycles
Welcome to V is for Voltage Forums
I'm sure our Community members and visitors would enjoy reading you blog, can we also post it on our site? http://visforvoltage.org/node/add/blog
Stleride
Moderator Team Captain
Moderators are community volunteers who help keep V is for Voltage Forums running smoothly, and provide forum support.
i got a nice one from www.ubuilditplans.com in fact i might sell it as i deciced not to use it
sounds like you are gonna have to use another jackshaft located closer to the pivot point (maybe located on the swingarm?), but that would require a chain tensioner going to the new jackshaft.
If an additional jack shaft were used at the pivot point of the swing arm very little of the torque would be transfered to the suspension. Using one shaft to pivot the rear suspension and placing 2 sprockets on that shaft would solve most of your problems. This would also simplify chain adjustments and eliminate the need for a chain tensioner.
ILBCNU
V is for Voltage
Moderator Captain
`Andrew,
Are there any new updates on your KZ750 Project?
BTW your KZ750 Electric Motorcycle Project Hand Books has been created, you can add a intro or what ever you want to the beginning.
A picture of what it looked like at the start of the project would be nice, we're working on creating a Image Gallery, a Slide show would really be a nice addition to your Hand Book.
So far this is our first and only Building Electric Motorcycle Collaborative Hand Books, we hope more soon follow.
Regards,
Board Moderator
Moderators are community volunteers who help keep V is for Voltage Forums running smoothly, and provide forum support.
`Andrew,
You were a very big part of creating them, or should I say you were part of the wind beneath our Wings, along with Chas Stevenson, our Webmaster David Herron just to name a few.

The Slide Show is still dream or should I say a work in progress. The Archive Team is working on one for there Old Voltage Forum Archives we may be able to tie into.
Thanks again for all your support of our V is for Voltage Community, it's really appreciated by all.
Regards,
Board Moderator
Moderators are community volunteers who help keep V is for Voltage Forums running smoothly, and provide forum support.
` ;)
Andrew,
Since we still don't have a on site Image Galley, and we don't want to continue delaying you, if you want to attempt to figure out how to use the V is for Voltage Community Photo Gallery go right ahead.
We just haven't had the time to learn how to use it yet, could use your help and input.
Regards,
Board Moderator
Moderators are community volunteers who help keep V is for Voltage Forums running smoothly, and provide forum support.
Andrew,
Looks great!! The only question I have is, "Do the motors get hot?" Might make a nice leg warmer in the winter but during the summer they could give you a hot seat. Other than that I think it's a great looking ride and I hope you will let us know how it runs.
Chas S.
Yep, looking good - I particularly like the birdsong in the background! (no really I do! - it's a subtle reminder of the benefits of electric ;-) )
I've stalled on my project - it's too cold even in the garage.
great progress!!
Just exactly how are the motors connected to the rear wheel? Pics?










Motors will not be in way of legs (hopefully). They were strategically placed. They will not be in way of passenger's legs either. Stock peg location is fine with this setup.
Are you also gonna use some sort of insulated barrier to separate the cables and connectors for the etek so that you dont accidently rub them with your legs?
Not a bad idea.
Where is it located? I'll have to try it when it is done
In Rio Rancho NM.
Oh and before you ask what the tank is doing in the last pic, its going back on! I just don't want to look at all that crap while I'm riding around, and the tank covers it all from my view nicely.
---
Avatar taken from http://www.electricmotorbike.org/
Anyone got one they might want to sell?
KZ750 Motorcycle Conversion
900 watt scooter
Pic from http://www.electricmotorbike.org/