Clanking from rear

[BKing]

Both of my Rad City did this clanking noise at certain pedaling speeds in gear 5 or 6. I got a new freewheel but it also had too much play. I was able to disassemble and remove a micro thin spacer to fully repair. This is not a bearing problem. Just a case of factory worker setting the necessary play without understanding that what he feels in his hand is magnified many times once it’s on the bike. Every freewheel has a different set of shims so yours may have thicker ones that would require removing one and adding one or two very thin ones. Some play is needed to keep the pedals from rotating with no pedal load and wheel turning.
Tried to post a video showing the clanking but this site only seems to allow pictures unless video is from another site.

 

[AHicks]

Wowee, that's interesting! So your pics are of the freewheel hub with the gears removed? Never had one apart (yet).

 

[BKing]

Yep, you can see the pawls that engage when pedaling and they make the normal clicking noise when coasting. These were ok. The Chinese used a weird smelling light oil on the bearings. Same as the new one I took apart. I used some good bearing grease but did not pack it tight. I actually did 4 of these since I have a spare wheel due to a bad motor under warranty. I fixed the motor too, cleaned something off part of the circuit board and resoldered the small joints.

 

[AHicks]

I tried taking one of these apart not too long ago, after seeing BKing's note here. Using plenty of patience and an average tool set, I was not able. Thinking correctly sized spanner wrenches will be required and a chain vice (or whatever that thing is called) - if you plan on re-using the freewheel anyway!

I can see exactly what's going on. Not the best design to start with. When the chain gets out on the smaller gears there's a lot of twisting load being taken by this bearing that's located way inboard from the chain/load being placed on it.

Bottom line, I can see where BKing is coming from easily. Thankfully, I don't need these smaller gears very often. Otherwise that rattling/clicking sound would make me nuts! -Al