ST2 Rear hub clatter

[SC Cruiser]

Hi. I purchased an ST2 back in March. Aside from a few minor glitches, which have generally been rectified by pulling the battery, there is one that I'm concerned about, which has now happened twice, both times after having washed the bike. That is, a clattering in the rear hub. This is not the free wheel or the chain, it is definitely coming from the hub motor, and it happens whether I pedal or not (coasting). It sounds like the magnets are clattering in the motor. I managed to get it to stop the first time by pulling the rear wheel. The second time pulling the wheel did not fix it. It did however go away after riding. Adjusting motor torque and speed by changing gears and pedal torque, combined with on and off coasting seemed to do the trick. I suspect that the fact that this occurred just after washing is coincidental, but maybe not. I wash the bike according to washing guidelines (gentle water rinse after wiping with wet rag; remove battery and insert dry rag in box etc...). Does anyone out there who knows more about these gearless drive hub motors know what might be causing this clattering? Has anyone else experienced this? Thanks

 

[siclmn]

I have a noise that is similar in my bike but the shop says it's the bottom bracket. A noise will telegraph and it is hard to find. There is no play in the bottom bracket but they say that is the problem. It has been sitting in the shop for 2 weeks now while they wait for a new one. For a bottom bracket to go bad in 1,500 miles is unheard of in my book. You don't ever pedal this bike with enough force to wear one out. This is under warranty, other wise I would have put a new one in myself. This has been a very fiddly bike from the start and with out the warranty I would have got rid of it by now. With only a year of warranty left I am still thinking of getting rid of it.
Remove the battery and reinstall it, yeah I have done that many times.

 

[smitty]

I have a noise that is similar in my bike but the shop says it's the bottom bracket. A noise will telegraph and it is hard to find. There is no play in the bottom bracket but they say that is the problem. It has been sitting in the shop for 2 weeks now while they wait for a new one. For a bottom bracket to go bad in 1,500 miles is unheard of in my book. You don't ever pedal this bike with enough force to wear one out. This is under warranty, other wise I would have put a new one in myself. This has been a very fiddly bike from the start and with out the warranty I would have got rid of it by now. With only a year of warranty left I am still thinking of getting rid of it.
Remove the battery and reinstall it, yeah I have done that many times.

Don't give up...I had some similar thoughts regarding "fiddly" when I first got my bike (ST-2); especially so when my OMNI unit went kerplunk. They sent me a new one which I installed myself and they have answered any other queries I have run into. (I once had to reset the torque sensor via the service mode on the OMNI unit). I got past my frustration by reminding myself how often I have to tweak my computers, iPads, phones, etc. Electronic's are just that...temperamental to say the least. This forum is great and full of useful info when you encounter a problem or simply want to know about a rear bag, tires, etc. Stromer folks are great. If I have a question, I generally e-mail them and get prompt replies with lots of helpful info in regard to my query...I too am suspicious about your bottom bracket...with the electrical assist, it is doubtful that you would put anywhere near the pressure you might normally do on the bottom bracket of an unassisted bike. Properly adjusted, it should run for thousands of miles...

 

[Robie]

Thanks all those members for posting instructions for helping me recalibrate my torque sensor on my St2. Seems to have solved my intermittent shutoff issues. Much appreciated thanks!