Finished bike

Finished prototype with Lead-Acid pack.	Fairing with credits.
Floating crank sprocket.	Ratchet assembly on the rear wheel.
Ergonomics are always important.  The throttle is reachable without shifting the hand around the grip and no fingers are over extended.	Lithium Ion pack on the bike.
Lithium Ion pack recharging from 12 V car battery with help of a custom charging system.	Lith-Ion pack controls and LED bank.

  In the parking lot at Birdwell Machine (taken by my Mom)


  Bike right after field trials at an Idaho trip.  There was some minor body breakage as
indicated by the red duct tape (I discovered that crazy glue doesn't set in 95 degree weather). 

Testing

    I've tested the bike initially with a small lead acid pack by taking laps around the machine shop and taking it on some of my favorite trails in Washington.  I couldn't wait until the Lithium Ion pack was fully functional.  Lead acid sucks!  It could pull through 4-5 small hills and that's it.  On flat ground around the machine shop I recorded a range of about 1.5 miles at 10 MPH.  At least the handling of the bike wasn't compromised.  Most of the weight is down low and ground clearance is the same as in the beginning.
   After I completed the Lithium Ion pack I tested for range again and clocked 13.5 miles around the shop at ~12.5 MPH.  The bike also has a higher top speed of 16 mph.  The night after everything was running I took off for a biking trip to Idaho.  I was most fearful that the electronics onboard the battery pack would die, but instead the problems the occured were minor and almost stupid in nature.  Once an electric connection came apart because I used a wire nut at the last minute.  A peice of the fairing holding the LED bank broke off when the bike was man-handled into the car with another bike and camping gear.  Finally one of the chains slipped because the sprocket I used was made for shifting.  The slightest misalignment causes immidiate shift of the sprocket (ie, chain moving around with bumps, etc).  This I hope to fix by changing the sprocket.  All these things were easy to repair in the field.  The bike survived the dirt and dust and even a crash on the singletrack.  My girlfriend's bike suffered some damage when she jumped off right before the bike went down the hillside.  It bounced along for good thirty feet in rocks, trees and roots.  And this was cause for a slightly bent wheel.  I'm not so sure my bike would have faired as well.  No doubt the fairing would have been torn to shreds.  The charger worked like a charm from the car's 12 V system.
    I am looking forward to acquiring a more efficient motor.  I've calculated that the EV Warrior is only 50% efficient in the relevant situations.  It has peak efficiency of about 75%.   This really robs me of range and power.

The future

    Well, I can say I did it and I know now.  There were definitely some good lessons on the way.  Most important is to not cheap out.  I would be a lot more happy now had I put it the extra time and money to get a better motor.  I would have saved hours of work and frustration had I spend $100 for proffesional PC boards and used more solderless connections, instead of soldering my own overcrowded boards in cramped spaces.
    I now know how to make a real kick-ass electric bike.  Picture a normally equipped full-suspension mountain bike that weighs 40 lbs, has 25 mi range without pedaling, 1000+ Watt motor, speed of 20 MPH, over 100 ft-lbs continuous torque without a mechanical shifting transmission, a slim shape and regenerative braking all for $3000...  Don't know about you, but sounds sweet to me.  There are a few key ideas I picked up along the way that makes this possible.  Now I just need $3000...  ahhhh.  Life's got too many compromises...

Credits

I'd like to thank the Birdwells (Mike and Jon), John Shwabacker, Tim Lang, and Bill Bailey for their help and advise.  And I'd like to thank Julie for the support.

Alex M
aka CopperSnot