Front view
OwnerPaul Master
LocationLafayette, California United States map
Web/EmailWebPage (not updated in quite some time) email image
Vehicle2000 Montesa Cota 315R
Competition trials bike, competed last three years.
MotorPerm Motor 132 Permanent Magnet DC
Perm 132 with custom fiberglass shroud and cooling fan.
DrivetrainConstant mesh, jackshaft. 6.66 overall gear reduction. Top speed ~28 mph
ControllerAlltrax 7234
Custom map
BatteriesA123 Systems 100 M1 cells per pack, 72.00 Volt, Lithium-Ion
Custom 66V 11Ah battery packs
System Voltage72 Volts
Using 72Vdc power supply, 13A. Every 5th charge or so I balance charge each sub-string using CellPro 10s.
DC/DC Converter
72 to 24VDC for cooling fan.
InstrumentationDrain Brain, now Cycle Analyst
Top Speed28 MPH (45 KPH)
For trials riding, typically cruise the loop between 15-20 mph, in sections anywhere from 0 to 15 mph, typically between 3-6 mph.
AccelerationHaven't timed it, but you cannot keep the front wheel on the ground in full power with fast throttle application.
Range2 Miles ( 3 Kilometers)
Highly dependent on terrain and style of riding. During a trials I typically run at an average of 20A, so good for ~30 minutes of actual riding.
Watt Hours/Mile125 Wh/Mile
On average. In very steep terrain consumes 5 times the power.
Seating CapacityNo seat, it is a trials bike.
Curb Weight175 Pounds (79 Kilograms)
TiresTrials tires
Conversion Time6 months for initial test mule. Continuous improvement ever since.
Conversion CostAround $8k for everything except batteries. Around $10K in battery pack development.
Additional FeaturesPower select switch, custom frame to mount the battery lower.

Future plans: Battery balance board for battery packs,
perhaps new pack using a different chemistry with triple the power density, clutch. Perhaps a second conversion.
1 first and 2 second places in last three seasons of Saturday Vintage Beginner Trials on the 2 line.
1 first and 1 second place in last two years of Sunday Class A Trials on the Sportsman line.

code by jerry