Bicycle Mechanics - Pawl chatter / rattle - SA IGH

I think I've tracked an annoying rattling sound to the sturmey archer x-rf5 hub on my bike. For quite a while I'd assumed it was the chain but I've ruled that out now. The noise occurs when I'm not pedalling and I ride over rough ground. . . and it sounds to me similar in tone to the sound of the IGH pawls engaging as one starts to pedal. It doesn't matter what gear I'm in. So I'm guessing that the rough ground causes the pawls to sometimes rattle loosely against the surface that they engage with. . . which makes sense to me as someone who's not yet dismantled an IGH fully and has a limited understanding of the design.

Does this theory sound plausible? Is this a known problem with IG hubs? I'm figuring that regreasing might solve the problem but that it might also be a sign of something being too loose/requiring tightening?

I'm planning to dismantle the hub this week and all advice is greatly appreciated as I'm finding the prospect of the task a little daunting.

Springs hold the pawls against the surfaces they engage, and I would think it would take quite a bit of bouncing to cause the pawls to rattle significantly. I would say a weak broken spring(s) would be the most likely culprit. As the springs failing can be a headache I would suggest you have replacements on hand when you do t he overhaul.

I thought that the springs simply push the pawls outward, i.e. away from the centre/axle. . . how does this hold them against the surface they engage with?

The surface they engage IS outward from the hub. The springs are what cause the rhythmic clicking as well as what insures engagement of the pawls when you start pedalling.

Hmm. . . so basically it would have to be a weak/broken pawl spring? Or could it be the driver rattling against something? It couldn't be the clutch as it's the same across all gears.

the pawls are the drive. one set drives in low , a different ones for high ..

Hmm. . . so basically it would have to be a weak/broken pawl spring? Or could it be the driver rattling against something? It couldn't be the clutch as it's the same across all gears.

I don't see the driver (4 pronged part that engages the cross-shaped clutch) rattling - held snugly by the cone. It would not HAVE to be a pawl spring, just seems to make sense from what you describe. No sense guessing further. Just overhaul, reassemble and adjust properly and you should have no problems.

Your Actuator (a component of the Driver Assembly) is rattling. This happens sometimes with the NIG hubs. It's no big deal and you can safely ignore it.

Here's (http://www.exacteditions.com/exact/browse/392/428/1755/2/30?dps=on) how to fix it, if you want to (instructions begin on page 31, explained on a 3-speed NIG).

Best,
tcs

I finally got round to dismantling the hub yesterday and fiddled around for some time, not realizing that there were new posts on this thread which it would have helped to have read beforehand. Oops.

Thanks for the link tcs, interesting. I was baffled by the driver assembly part. . . didn't get my head around the mechanics involved there. But I've just had a quick test-ride on my newly greased (greased to death) hub and the noise has gone for the moment. I still don't know if there was a single cause or if it was down to general looseness on the driver side of the hub. . . but I'll see how it behaves over the coming week and whether the noise returns. Fingers crossed.

And apparently there's nothing wrong with the pawl springs.

I'm glad you got your hub fixed, as I have seen a
great number of these landfilled over the last 40
years and they deserve a better fate.

It will not be an issue now for quite a while, since
you disassembled and greased everything, but
these can make quite a bit of noise if lubricated
with too light an oil (e.g. Triflow). I've finally
come down to using a combination of six or eight
drops of Triflow and maybe eight or ten of Singer
sewing machine oil in mine. I think Jobst Brandt
recommends 30 weight:

http://yarchive.net/bike/sturmey_archer_hubs.html

but I find this to be a little too heavy. Anyway, Mr.
Brandt seems to have a personal vendetta regarding
these hubs (unwarranted in my opinion), so this may
be his underhanded way of disposing of the remaining
ones.

Mike Larmer

After seeking a range of opinion on these forums I opted for the official Sturmey Archer grease. . . I had been thinking about converting to oil but eventually was persuaded that the newer generation of hubs do run better on grease. Having used it it strikes me that the Sturmey Archer grease is probably ideal for the job.