Loose Profile Hub

Last month I epoxied the hub of my Profile to the spindle. It had developed a
bit of play between the cranks and the wheel. The cranks were tight to each
other but when I applied pressure to just one pedal, there was a slight but
noticable lag till the wheel turned. I believe this play is responsible for
the squeak some people get with these hubs. The spindle and hub are press fit
with slots and a square key at each end.

I used System Three epoxy because I have tons of it around and it is a low
viscosity epoxy so it will penetrate places that other epoxies will not. I
used the slow hardener since it has the lowest viscosity. It will harden over
night at room temperature.

I mixed the epoxy according to the instructions, measuring carefully with a
horse syringe that I bought from a veterinarian. I did not use the needle,
just the syringe. I put the epoxy back into the syringe and inserted the
spindle into the hub until the crank splines were fully inserted. Then I used
the syringe to apply a small bead of epoxy around the spindle and against the
hub. With the hub supported on two large wood blocks I tapped the spindle into
the hub by holding a small wood block on the end and hitting the block with a
metal hammer. I was careful to maintain the bead of epoxy around the spindle
the whole time I was tapping it into place and when the first square key was
fully into the hub, I started filling the void between the keys completely.

When the spindle was centered in the hub, I wiped the excess epoxy thouroughly
with a little acetone and installed the spacers, bearings and cranks and
tightened down the end bolts. Then I removed the end bolts to check that the
cranks were equally onto the spindle, and reinstalled the bolts. I left the
wheel against the wall, with the square keys up, overnight. I am not sure what
will happen if I have to remove the spindle. This epoxy softens at a low
temperature so I may need to use a propane torch.

I have been riding it for about a month and I took it to Moab for the weekend.
I have been riding Sun Peak, Carbonate, and Chokecherry Gulch all of which have
stretches that are steep enough to test my strength. There has been no sign of
the play that was there and the hub feels solid.

Never hit the spindle directly with a metal hammer. Always use a block of wood
between the hammer and the spindle. Always support the hub on some blocks of
wood as close to the spindle as possible so that you do not stress the spokes
in any way. I drove the spindle out with a wood dowel. Clean all parts with
acetone before assembly. This will allow the epoxy to adhere.

Idaho Joe

Re: Loose Profile Hub

No need to explain, Joe- heh!- no need at all.

Christopher

Interesting. Did the epoxy treatment get rid of any audible creaking in the hub?

I got my Profile hubs and looked at how they were put together I have been thinking that I might eventually have to do something similar. I’d probably use Loctite instead of epoxy. I had thought the Profile hubs also used a pin to hold it together, but it’s just press fit with a keyway. That surprised me a bit. Perhaps we should suggest to Profile that they put some Loctite retaining compound in there when they assemble the hub.

Do they use two shorter pieces for the key or is the key all one long piece?

john_childs