Hi group,
I'm stumped on what is going on with my rear hub. I have a Sturmey Archer X-RDC with a 9 speed cassette and recently replaced the free hub body due to a nasty crunching sensation and sticking hub when freewheeling. The free hub body had a big crack in it with chips taken out of the pawls. Popped in the new body and it spun well and felt great on the stand. I go for a test ride and it works well with no crunch but I'm still getting a sticking hub. It's not constant but almost a rhythmic catch that's not quite hard enough to throw the chain. I have also noticed a strange rhythmic shake to the rear wheel when I spin it fast on the stand now. Any ideas?

Apologies in advance. Gets Popcorn.

Someone will tell you the right answer later.... whilst you are led around the houses until someone points you in the right direction.

I assume from your description that the new free hub is free wheeling freely on the stand without the chain. However when you put the chain on and go for a ride then whilst pedalling you experience 'catching'... is the 'catching' still there when you are free wheeling? Then when you have the bike on the stand and spin the wheel, the hub should be free wheeling, you still get what you perceive to be catching.

Perhaps you need to look beyond the new free hub itself and to the wheel. Hub bearings. Take the wheel off and spin the wheel in your hands. Is it smooth or does it occasionally grind? Is the wheel true... perhaps it is hitting the brakes but that would, hopefully, be and audible thing. Stiff link in the chain... and so on.

Thanks for the reply. I put the bike back on the stand and it freewheels fine with no chain catch but does continue to have a strange shake to the wheel when spinning. The chain is good and the brake is a drum brake with no rubbing that I can find.

Bicycle wheels are rarely balanced. You'll notice that a wheel spinning freely will always stop with the same point at the lowest.
The common opinion is that there's not enough functional improvement to merit the effort of balancing bike wheels.
With the weight of a rider pressing down, spin rate, weight etc, it simply doesn't matter.
But the unbalance is still big enough to be easily seen when spinning a wheel in a stand.
If it bothers you, balance the wheel.
Let it settle, add weight to the highest point.
Spin, let settle, add more.
Continue until the wheel will settle at no defined point.

Yea I get that but this is quite a bit more severe. I'll see if I can get a video later as well as check the other bearing. The shake rattles the whole bike on the stand and seems to occur at the same section of the wheel/hub rather than shaking constantly. I don't notice it too much while riding but thought it might be related to the hub catching at a similar rhythmic pattern which only happens while I ride and not on the stand. The wheel is slightly out of balance but nothing I usually worry about.

These kinds of sets of problems can be fun and hard to solve at the same time. But for us to help out more data is needed. First is whether the shaking was happening prior to the work done. Just because one doesn't notice a problem does not mean it's not happening. We humans tend to attach "the inception" of a problem to the moment we discover it. Many problems have been going on for a while but not yet perceived by the rider, I might say most problems lay hidden but "active".


So out of balance wheels spinning can cause hop/shake on a stand where the mass of the wheel is a significant portion of the system's and where the stability of the bike is less then when on the road. This problem is easily solved or at least played with by attaching tiny weights (solder wrapped around a spoke nipple) or removing weights like reflectors.


Hub bearings are another source of shake/wobble in a spinning wheel. From very loosely adjusted bearings that allow much hub/wheel slop about the axle in a rather inconsistent manor to a very rhythmic manor when a hub bearing has one too many balls in it. This over filled with balls bearing will have it's rotation happen in two axises at the same time. One is the rim revolving about the axle and the second is the off set between the bearing's inner and outer surfaces that cocks the hub askew from correct. But as the rim is rotated around the axle this offset/askewness also rotates at about half speed compared to the wheel. So in in a bike this condition looks like the rim is out of true yet the out point is shifting about the rim's circumference. I don't know what form of bearings your hub has so I don't know if this too many balls are even a possibility.


Was anything else done to the bike or wheel when the freehub body work was done? Like a tire being remounted or tube changed? Can you see any actual rim/tire run out (laterally or radially), is it consistent?


As to the catch or stickiness- Hubs can be odd things especially if radial contact cartridge bearings are used. Very small dimensions can have big effects on things. Many of the cartridge bearings used in bike parts really want a tad of end play to not wear rapidly. The problem is that the bike industry hasn't completely tooled up to control the few thousandths of an inch which can be the difference between good function and sloppy or tight. Add in that many freehubs use simple "o" ring like seals which might be unlubed or too compressed to allow free spin before the break in period is done.


Of course that other then wheel problems are causing the catch. No brake pad or frame rubbing. Andy.