OwnerTom Piraino
LocationWest Bridgewater, Massachusetts US map
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Vehicle1990 Suzuki Katana
sportbike to EV bobber
MotorD&D Motor Systems, Inc. ES-15 Series Wound DC
Tried advancing brushes 10 degrees, but it lost a lot of starting torque. went back to neutral timing and it's fine(no arcing). probably because batteries sag to 80-85 volts at full throttle.
Drivetrain520 x ring chain 13/56 sprockets
ControllerCurtis 1221C
mounted on a big heat sink
Batteries32 Skyenergy calb 70ah, 3.20 Volt, Lithium Iron Phosphate
24 cells inside frame,8 in saddle bags.
System Voltage102 Volts
Charger 8x10 amp and 1x3 amp
Chinese chargers from battery space, 1 for every 4 cells. Cells stay pretty well balanced with this setup. The chargers get hot but they're still working.
HeaterMotor DOES get hot if you beat on it.
DC/DC Converter none
20ah aux batt w/separate 3 amp charger
InstrumentationLarge screen Cycle Analyst HC/HV. Wonderful little instrument.
Top Speed70 MPH (112 KPH)
Lost a little speed with the lithium conversion, but gained a little acceleration(lighter) and doubled the range
AccelerationFrom 10mph to 60mph it's about like a sportster or bonneville. Below 10mph and above 60, it's about like a 250.
Range40 Miles (64 Kilometers)
40-45 miles if you ride like an old lady(40-45mph and easy on the throttle), 35 miles if you ride it like you stole it.
Watt Hours/Mile170 Wh/Mile
160-180@40-45mph, 200-240 if you beat on it
EV Miles
Start:22,000 Miles (35,398 Kilometers)
Current:22,500 Miles (36,202 Kilometers)
Total:500 Miles (804 Kilometers)
Seating Capacity1 adult
Curb Weight500 Pounds (227 Kilograms)
lost 90lbs going from lead to lithium, but it's still no lightweight
TiresMetzeler 110/80 zr17 front, 130/70 17 rear
Conversion Time500 hours?
Conversion Costover 6 grand
Additional FeaturesExpanded metal bodywork!
Went from lead to lithium 10/11. Lost about 5-6 mph top speed(75 to 70) with the same gearing, but gained some acceleration because it's 90 lbs lighter

code by jerry