matimeo

So I've been having drama with the wheelset that came with my cross bike that I use to commute through the winter- I'll leave the details for another post. To get me up and running while I deal with those wheels, I bought the only wheelset I could find that fits my bike (11 speed, 130mm spacing, disc brakes). Enter the AEROMAX RACE DX 700c 29er Disc Bike Wheelset 28/32H 7-11s Shimano/SRAM. No specifics were given on the hubs or freehubs, but they're branded Aeromax (the hub). Can anyone identify the freehub body below?









I'd never worked on a bike with a freehub that didn't thread into the hub- this one is just held in by the end nut that also holds in the cartridge bearings: but I learned they aren't that uncommon when I looked on the Park website about freehub maintenance. But man, it rolls rough. It's noisy and gets a lot of resistance. I posted a video below to show you what I mean. You can make the wheel move backwards by pedaling backwards and it slows the wheel down pretty fast once you get it spinning. I've never had a freehub create that much friction. I checked to make sure it was lubed well, and I don't have it over-tightened. In fact, right out of the box, when I spun the freehub, right away I thought it felt too stiff. This just seems to be how it rolls. I'm wondering if it's normal, something's wrong or it's just cheap. Or maybe they just need broken in? I'd like to be able to ID the freehub, but if I can't I guess I'll try their customer service.

dragging freehub video


Thanks in advance.

M

richart

It came with all that grease?

matimeo

Yep, that's what it looked like when I pulled it off, right out of the box.

Davet

I'd wipe all the grease off except what's on the pawls then reassemble and see what the result is. That's an awful lot of grease.

FBinNY 

It's the same basic design as Campagnolo.
I can't say anything for sure, but It may be that you have it paced wrong, so the end is butting up on the hub bearings, or the outer seal is pressing on the shell (which ever happens first).

This design depends on the freehub being located along the axle so the pawls engage the ratchet ring, but nothing else touches except the outer seal. Check the spacing, and locate the freehub along the axle so it's in the right place, and the rest should drop into place on it's own.

matimeo

But do you think that could cause that much drag? I just tried to take it out for a spin; any time I wasn't pedaling and putting some pressure on the freehub, the chain was going completely slack and not rotate with the cassette because there was too much drag for it to run backwards.

I'll rub it off and give it a shot, but I'm skeptical that it would cause that much drag.

matimeo

I pull it apart again and see if I can make sense of it. FBinNY, I think I still owe you some pizza or something from some great advice you gave me a while back on a front derailleur. Thanks for your help.

FBinNY 

OK, I can't see the other half, and the design is somewhat different from Campy, which used a fixd spacer which was one with the axle to locate the freehub.

Yours has that spacing sleeve, and I suspect that the freehub uses a cartridge bearing similar to the one on the hub. So, is that spacer is the right length, and both the hub and inner freehub bearings are properly located, with their inner races supported from the back (usually there's a tube between the bearings in this design) the tube will keep the freehub in the right place for the respective ratchet parts to line up correctly.

Your problem may be a missing spacer, no tube between the bearings, or something of that ilk. I'm sure that once you understand the design, you'll be able to dope out what's wrong, and solve the problem.


BTW - I scrolled back for another look, and the photo of the hub is gone. you might want to check into that.

matimeo

I refreshed the links. I always have a problem with google photos url's- they don't seem to stay static. I moved the pictures to an album, hopefully that helps.

andr0id

That cassette body looks exactly like the body they use on my PowerTap hubs.

Not sure who makes it. DT Swiss makes the GS parts, but not the standard G3 parts.

CliffordK

Rather than buying a new freehub, I'd try to figure out where your excess friction is. And rebuild your freehub if necessary.

I'm assuming two more sealed cartridge bearings in the freehub. Do all the bearings feel smooth?

Pull the axle out and roll it on something flat. Or twist it in place and watch for movement at the end. Is it 100% straight?

One of the issues with the sealed bearings. I suppose it is similar with the cups and cones. Anyway, in your case, if you apply sideways pressure to the cartridges, then it will substantially increase the friction, and perhaps is damaging to the bearing cartridges. So, if the cartridges are designed to be bolted tightly to the axle, then there should be steps in the axle, or spacers designed to hold them in place when you tighten down the bolt. Or the bolt should be designed with a lock nut to apply loose pressure.

I suppose just verify you're not missing a spacer, perhaps between the freehub and the hub. And, that the spacers are wide enough. And don't over-tighten against the bearing cartridges.

Cartridge bearings are typically "standard sizes", and can be removed and replaced if necessary. A local bearing shop should be able to help you find replacements.

I'm not sure about grease on the pawls. It shouldn't cause substantial friction, but a viscous oil would be lower friction. It is up to you. Either will work.

davidad

This it? Joytech 10 Speed Freehub Body S132100009 Camber/Enduro/Epic/S-J


I would leave the factory grease in place.

matimeo

That looks very similar, but mine is an 11 speed. The end isn't exactly the same.

matimeo

So I think the hub is breaking in because it is spinning a lot more freely than it did originally. I just went out after doing nothing with it for a few weeks (bad sprained ankle) and it spun a lot better- more like a regular wheel.

HOWEVER, I'm still having a weird problem. When I'm on the bike and I put the cassette into a smaller cog (higher gear), the chain stops freewheeling and falls totally slack- which worries me it will going into the spokes or something. BUT, I can't recreate the problem on the work stand- only happens while I'm sitting on the bike. I'll spin it in the same gear, same speed, and it freewheels just fine in the stand. Any guesses what's going on?

I did just put on a new chain on the old cassette, but I don't think that's causing any stick. Cassette only has about 2,500 miles on it.

Andrew R Stewart 

I have a Phil freehub that still tugs on the cranks after 2000+ miles. I suspect your issue is more of a breaking one. If there are any removable seals between the body and the hubshell you might remove then as an experiment. Andy.

matimeo

I pulled the freehub off again today- it's pretty basic. There is a spacer in there and the freehub just pushes against the cartridge bearing in the back for the axle. I'm used to threaded on freehubs, so it's weird it's just floating there. I don't have the axle bolts on too tight, so that's not the problem. The thing is just clunky. The little clutches or gears that allow to pedal in one direction and freewheel in the other are held into place by a wire ring that goes around them. I'm 99% sure it's the freehub that doesn't spin freely enough to let the chain relax. I even replaced the rear derailleur with a brand new one to make sure that wasn't the problem.

Tomorrow I'm going to see if anyone from randombikeparts.com can help me figure this out (maybe same issue with other sets they've sold?). I don't know if they can nail down the manufacturer or if said manufacturer has any real customer service, so to speak. I think it may be a joytech hub.

matimeo

So I've ruled out any problems other than the freehub, and it runs smooth now when the bike is in the stand. But while I'm on the bike, the chain gets slack it it when I let the freehub/cassette freewheel.

So what it it about being on the bike that causes the problem? Could it be flex in the axle causing the freehub to not spin freely when there is weight on it?

davidad

That may be the problem. That type of freehub is nothing more than a glorified freewheel with the axle cantilevered out and bending under load.

xenologer

I was wondering about that...
haven't owned one of these types of hubs, but it seems to me
you have an axle, a hub on that axle with it's 2 bearings
then a freehub body independent of the hub on the same axle with its own set of bearings
so, about 2/3 of the way thru the axle there's a gap where any load from either the wheel or the freehub on either side gets focused and tends to bend the axle

seems kinda like a bad design, road bike exclusive? is this considered high end?

dabac

Cicrus Monkey uses the same design on their MTB hubs.


As with a lot of bicycle parts, "good enough" is the most common target. Clever marketing can even make "good enough" sound like a desired feature.


It's not really a problem worth fixing as long as the axle is rigid enough. With the right spec, it can be.