On 5/19/2020 4:58 AM, Duane wrote:
AMuzi wrote:
On 5/18/2020 4:22 PM, wrote:
I just gave my 3 speed sturmey AG dynohub (internally an AW) a service.
I'd been having an intermittent clunking noise, maybe once a ride, and
I'd assumed it was the clutch slipping under load, hey ho it's an old
hub. So I opened it up, gave it a clean, replaced the clutch and pawl
springs, and put it back together. I took it for a test ride and it's
now clunking every half turn of the pedals, in all 3 positions and
worsens under load. Before the clunk there is noticeable resistance for
a moment. Freewheels fine.

I'd love any thoughts. Most other posts I've read about noise are
grinding or just the pawls clicking. I'm stumped.

I'll be reopening the hub tonight to check I've reassembled correctly.
As this was the 3rd time I've serviced this hub, I wouldn't be surprised
if I'd got flippant.


Doesn't sound very 'Sturmey' in that a regular noise should
not be possible in all gears. I would look at pedals/cranks
(crank pins?) crank bearing for a 1/2 rotation noise first.

Any chance the sprocket is worn or bent? Have you changed
the sprocket or spacers or sprocket dust shell recently? A
damaged chain noise should have less frequency than 1/2
pedal rotation but sight it anyway for links unlike the
others- takes a second.


Not familiar with a dynohub but the last time I had a clunking noise every
half stroke it was the preload on the BB.


Agreed but that sort of thing is normally easy to diagnose
and very unlike hub noise.

Hold front brake firm, hold a desk or doorway in the other
hand. Stand on one pedal and push as hard as possible,
reverse cranks, repeat. If unclear, have assistant listen
and or touch (RH cup, chainring bolts etc) to hear or feel
movement.

If pedals are suspected, remove and turn pedal spindle in
your fingers or swap in a different set to test.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971