I took it apart today after viewing a YouTube video I found online. There are 3 planetary nylon gears inside the the motor drives inside a metal gear ring in the hub. Everything looked fine except very dry of grease. I regreased them and reassembled. Just took a ride and although not totally resolving the rumble definitely improved to acceptable. If anyone else needs info I did find the nylon gear assembly on Amazon at very reasonable prices.

I'm going to try taking it apart but won't get to it for another week or so. It feels like a bad drive gears set maybe.

My motor has over time developed a rumbling noise that also vibrates up through the seat post. Has anyone tried to take these apart to repair them? or am I faced with sourcing a complete new wheel from Rad? Bike has 6,000Kms on OD.

Curious as to just how long a battery should last before it is expected to reach its end of life span (years)? My bike its almost 3 years old now and the battery seams good as new. Just anticipating how old they get before everyone is facing buying a replacement?

My RR5 is experiencing bearing issues also. They are squeaking like dry, but Rad is no help when I contacted them for instruction on taking apart to inspect. I searched web - nothing much there either, but I think the cone bearings have 6mm balls in them. I took wheel to a bike repair shop but they seemed hesitant to take apart. I then contacted Rad and they would sell me a new complete front wheel for $175.00. I may wait until spring (no riding here in Canada in winter anyway) and just bite the bullet.

Yes I?ve already tried that and ruled it out.

Yes I've ruled out all those possibilities already while working with the Rad rep. Thank's though for the thoughts.

My front wheel has developed an annoying squeak that I can't make go away. I've narrowed it down to the front axle bearings (or so it seems). Have chatted online with Rad several times in past few days to trouble shoot, but they aren't any help. Can't advise me how to service the bearings. Pretty sure they need lubrication.
Has anyone experienced this issue? Does anyone have instructions for me on how to disassemble and lube?