| Owner | Andi | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Location | Lucerne, Lucerne Switzerland map | ||||||||
| Web/Email | WebPage | ||||||||
| Vehicle | 1981 Yamaha RS 125 DX | ||||||||
| Motor | Golden Motors HPM-10KW fan cooled Brushless DC Very good performance so far. Unfortunately, the manufacturer did not provide detailed information about their power measurements which would be needed for declaring the 30 minutes maximum power. | ||||||||
| Drivetrain | Chain Drive | ||||||||
| Controller | Kelly KEB72121E, 24V-72V, 200A Runs well, easy to set up. Very good acceleration. It's a little bit noisy on low revs, but who cares ;-) | ||||||||
| Batteries | 72.00 Volt, Lithium-Polymer DIY made of "Graphene Lithium Ion Polymer" cells from Shenzhen WESTART Technology Co. Ltd. 40 cells, 3.6V, 20Ah, 10C continuous discharge. The total pack is 2p20s, 2.88kWh and water tight. Water cooling built in but not used. Hardly ever reaches 45°C. | ||||||||
| System Voltage | 72 Volts | ||||||||
| Charger | 2x 84V 3.4A Two XieTong C300, quality budget chargers from China. On board, 2x300W, they fit nicely under the old tank. I would not recommend them for EMC reasons. | ||||||||
| DC/DC Converter | Delta B70SR12424A 12.4V, 300W, water resistant IP67, small and powerful. But I would not recommend it for EMC reasons. | ||||||||
| Top Speed | 68 MPH (109 KPH) With a sprocket ratio of 12/45 | ||||||||
| Acceleration | 3.5 seconds for 0 - 50 km/h (30 miles) 10 seconds for 0 - 100 km/h (60 miles) I haven't seen a quicker 125 two stroke motorbike :-) | ||||||||
| Range | 40 Miles (64 Kilometers) On hilly curvy roads, with max speed of 80 km/h. 50 km is never a problem, I've done up to 76 km. | ||||||||
| Watt Hours/Mile | 46 Wh/Mile Average over the last 1000 km. | ||||||||
| EV Miles |
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| Seating Capacity | 2 adults (155 kg payload) | ||||||||
| Curb Weight | 265 Pounds (120 Kilograms) Only 10 kg more than the original motorbike. | ||||||||
| Tires | 2.75x18 and 3.0x18 | ||||||||
| Conversion Time | 5 years. Started in November 2015, finished in July 2021. | ||||||||
| Conversion Cost | Over 8000$, I stopped counting. Plus 4500$ for electric safety tests, EMC and MOT (required in Switzerland). | ||||||||
| The project has given me a lot of fun and a lot to learn. I’m very pleased with the outcome. The motorbike is really fun to ride, nimble and light :-) Learnings: - Figuring out how to pack the batteries into that little space took me a lot of time. - Also figuring out the regulations to get it road legal was not easy. In Switzerland electric safety and EMC needs to be tested from an accredited test lab. - After the first controller (Kelly KLS7250D) overheated, I replaced it with the KEB72121E and added active cooling with a fan. - The external charger is very useful for longer trips. With the extra 1kW power (1.6kW total) I can “fast” charge within 1.5 hours. Things I will improve: - The LCD SOC display is hard to read in day light. I want to use the old rev gauge to display the battery voltage. Watch my YouTube playlist for more details and impressions: WebPage | |||||||||
1981 Yamaha RS 125 DX
“Andis Flitzer”
Last Updated 11-26-2023
Copyright © 1997-2024 by Mike Chancey