Last week the planetary gears in my oil cooled Bafang SWXH gave up. 😦
Pushing the ICE Sprint at up to 1300W with a 14s (58V) LiPo battery and 35A controller in a 26″ wheel finally took its toll. The Nylon planetary gears shredded while accelerating on a slight uphill.
Since the SWXH was ‘well used’ to begin with I was expecting a defect of the clutch or Nylon gears would end my ‘stress testing’ of that little hub motor at these power levels. Nonetheless it choose a very inconvenient moment in the middle of a heavy downpour 9km from home to stop working. At least the pedalling kept me relatively warm while I got soaking wet. 🙂
I haven’t decided yet what to do next.
The easiest and cheapest would be to get new Nylon planetary gears and continue with the current setup in 26″ wheel since it worked very well in the last one and a half month or 1400km. My preferred solution would be to get steel planetary gears but unfortunately they are not available in the size to fit the Bafang SWXH.
Simply getting new gears and run them till they break again might not be that bad of an idea. If they only last 1400km as well I’ll have to change the setup.
I could swap the SWXH to a 24″ wheel to reduce the stress on the Nylon gears. While that would give me a more rigid rear wheel it would also reduce the ground clearance of my Sprint. Normally that’s a good thing but since I’m using the ferry across the harbour every day the Sprint frame would scrape on the gangway sometimes.
Reducing the controller setting from 35A to 25A might be enough to lower the stress on the gears and I can keep the 26″ wheel.