Bicycle Mechanics - Freehub bolt was not attached (rear hub question)

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.




KeyserSoze81
09-11-12, 11:50 AM
I have a 2010 Specialized Secteur Triple, and this is my first time working on a hub.

So for the past three months, I have heard a knocking from the rear wheel whenever I would go over a bump. I thought that it was simply chain slap, but after removing the chain, the noise was still present. I bought a chainwhip and lockring tool and took my hub apart last night. When I removed the axle, the freehub body just fell off - the fixing bolt was completely loose and bouncing inside the hub! It tightens from the non-drive side (requiring a longer 10 mm allen wrench).

There did not appear to be any damage (to my untrained eye) so I snugged it up as best I could, repacked the bearings, and adjusted the cones.

Two questions:

1.) What purpose does the fixing bolt serve? The bike seemed perfectly operational, but is that simply because everything else was tight?

2.) I adjusted the cones last night (again, first time) - now the quick release axle has to be extremely tight to eliminate side-to-side play. Is this the elusive point that the park tool manual wants me to achieve? Or would that suggest that the cones should be tightened more?

Once this is done, I'm installing my new, cheaply acquired ST-R500 brifters, so any help is appreciated so that I can get to the fun stuff. Thanks!


mrrabbit
09-11-12, 11:59 AM
Is this a low-end Shimano or a generic from Taiwan / China?

Are you certain it uses a 10mm, or is it actually an 11mm allen wrench?

Does the freehub have an allen head built into and does it thread into the hub - or does the freehub mount onto a star shaped post of sorts?

=8-)

onespeedbiker
09-11-12, 12:02 PM
Well for one thing the fixing bolt will stop the knocking and the shifting should crisper; however eventually the freehub would have fail. If the axle is loose in the hub it means you didn't get the cones tight enough. Is this NOT the elusive point that the park tool manual wants you to achieve. the cones clearly need to be tightened more? They should be just tight enough so they don't have any side to side play )at all) but not so tight as they bind. With some hubs you may have to account for cone tightening with the QR but it's best to find that elusive point without the QR and if you feel binding with the QR then back off one side a little. Regardless but it should be standard QR tightening, not extremely tight.


fietsbob
09-11-12, 12:11 PM
Shimano a sleeve bolt that joins the freehub and the spoked hub,is a 10mm hex inside .

IDK how many others copied that mechanical connection.

axle has to come out to get to it .. , use long end of a 10mm allen wrench , to fit inside that far.

KeyserSoze81
09-11-12, 12:23 PM
Well for one thing the fixing bolt will stop the knocking and the shifting should crisper; however eventually the freehub would have fail. If the axle is loose in the hub it means you didn't get the cones tight enough. Is this NOT the elusive point that the park tool manual wants you to achieve. the cones clearly need to be tightened more? They should be just tight enough so they don't have any side to side play )at all) but not so tight as they bind. With some hubs you may have to account for cone tightening with the QR but it's best to find that elusive point without the QR and if you feel binding with the QR then back off one side a little. Regardless but it should be standard QR tightening, not extremely tight.

Okay, that was what I was worried about. I will tighten it tonight.


Shimano a sleeve bolt that joins the freehub and the spoked hub,is a 10mm hex inside .

IDK how many others copied that mechanical connection.

axle has to come out to get to it .. , use long end of a 10mm allen wrench , to fit inside that far.

Correct, that is the design that I have.

davidad
09-11-12, 04:22 PM
Well for one thing the fixing bolt will stop the knocking and the shifting should crisper; however eventually the freehub would have fail. If the axle is loose in the hub it means you didn't get the cones tight enough. Is this NOT the elusive point that the park tool manual wants you to achieve. the cones clearly need to be tightened more? They should be just tight enough so they don't have any side to side play )at all) but not so tight as they bind. With some hubs you may have to account for cone tightening with the QR but it's best to find that elusive point without the QR and if you feel binding with the QR then back off one side a little. Regardless but it should be standard QR tightening, not extremely tight. A properly adjusted cup and cone hub will have a small amount of play that will go away when the quick release is closed and compresses the axle a few hundredths of a MM.

FBinNY
09-11-12, 05:53 PM
That type of hub is supported on bearings at either end. The freehub bolt serves to make the hub/freehub combination into a single rigid module. Picture if you lay a pencil between 2 supports. It rests straight across, and if you push down in the middle, it'll flex a bit but that's all.

Now imagine that you took a pencil, removed the eraser, and pushed the end onto the eraser of another pencil, making a single double ended pencil joined by the eraser. Lay that across 2 supports, and at the lightest touch it'll sag in the middle, if you push harder it'll come apart at the eraser. The only way to make it rigid is to splint it across the connection with something like a piece of rigid tubing, so it acts like the first pencil did.

Likewise your hub, The bearings hold the freehub spline into the hub so it can't come out. But as the chain tugs on the cassette, especially on the larger inboard sprockets, the hub and freehub will deflect at the non-rigid joint, and since they're turning it'll cause wear there. Having it properly tightened prevents that deflection and wear preserving the integrity of the joint.

Note, that if you rode any distance o rode hard long enough, the steel freehub doesn't suffer, the aluminum hub shell does, and since it includes the wheel it can be an expensive problem.