Gearing

The stock gearing on the 1986 Yamaha YX600 Radian is 16-44 with a 530-104 chain. According to the speed/RPM calculator, here are the calculations:

Stock tire: 130/90-16"
- diameter: 25.21"
- circumference: 79.21"
- revolutions/mile: 799.92
Desired max speed: 70mph @ 4500 RPM
- wheel RPM for 70mph
  - 800 rev/mi
  - 70 mi/h = 1.17 mi/min
  - 800 rev/mi * 1.17 mi/min = 936 rev/min
  - 4500rpm / 936rpm ~= 1:4.8
- Using stock driven sprocket
  - Stock rear sprocket: 44
  - New front for stock rear: 9.15 (??)
- New sprocket ratios
  - Rear sprocket: 60
  - Front sprocket: 13

Batteries

Optima Yellow Top D51 12V 45Ah
6 in series: 72V 45Ah
Size: 9.31" x 5.06" x 8.94" = 421 in³
Weight: 26 lbs
- Column
  - Size: 9.31" wide x 33" tall x 8.94" deep = 2747 in³
  - Weight: 156 lbs
Price: $750 ($600 after rebates expiring Sep 15)

Cloud EV Lightning Bolt 3.2V 100Ah
15 in series: 48V 100Ah
Size: 2" x 6.3" x 11.1" = 140 in³
Weight: 7.75 lbs
- Column
  - Size: 30" x 6.3" x 11.1" = 2,097.9 in³
  - Weight: 116.25 lbs
Price: $2,835

Cloud EV Lightning Bolt 3.2V 200Ah
15 in series: 48V 200Ah
Size: 2.2" x 8.6" x 13" = 245.96 in³
Weight: 15.5 lbs
- Column
  - Size: 33" x 8.6" x 13" = 3689.4 in³
  - Weight: 232.5 lbs
Price: $6,735

Frame: Using an existing 1986 Yamaha YX600 Radian I have.
- free
DC Motor & Controller: Separately excited motor for regenerative braking capabilities
- D&D SepEx: $1425
Batteries: Holds the juice. Obviously needs to be at 72VDC
- Optima Yellow-Top D51: $125/ea = $750
Charger: Mounted on bike to plug-in
- Zivan NG1: $525
DC/DC Converter: Supply 12V to on-board electronics
- Sevcon 72V to 13.5V 300W: $250
E-meter: Monitor battery bank voltage
- Xantrex Link-10: $200
- Prescaler for 0-100V systems: $90
Contactor: Allows the ignition switch to engage the battery to motor.
- Albright SW-200: ~$125
Fuses: Need a heavy duty fuse to keep the bike from frying.
- ANN 400 w/ holder: $40.
Throttle: Control the speed using an electric throttle
- Magura Twist Grip: $50
Sprocket and Chain: Oversized sprocket could cause the chain not to fit.
- Sprockets and Chains: $250
Miscellaneous metal work: New tank top, etc
- $300

Total projected cost: $3730