1989Pre 

The rear hub on my MTB is a bit loose, that is, I can wiggle the wheel side-to-side and there is play at the bearings. Not much, maybe a millimeter or two. The bike rides fine, and when I spin the wheel, it spins freely. Is this an issue that I need to be concerned about? I contacted Performance to see if they had replacement bearings for the Forte hub, but they did not (a 26" Forte Terramax wheel). Is there a way to adjust (tighten) the bearings if I needed to?

Andrew R Stewart 

Most likely your rear hub uses loose balls in what is called a cup and cone design. This type of bearing is quite easy to take apart to discover what's actually going on. From mere loose bearing adjustments to worn/damaged parts is possible but w/o X ray vision you won't know and only doing a bearing adjustment won't address any need for lube or replacement parts. I suggest you do a little homework on what you have and how it's assembled, Park Tool's Big Blue Book Park Tool | Repair Help Articles is a good first source for detailed info and a list of tools to do hub servicing.

Given the M80's age and taht the hub was likely loose long before you noticed it, I would wager that you will find worn/pitted axle cones, possible hub shell cups too. Back in the day we use to tell our customers that this in depth level of servicing should be done at least every 5 years, sooner if a lot of rain or more than average miles are at play. Andy

FastJake

The first step is figuring out whether you have loose ball bearings or cartridge. This is a common problem on loose ball hubs, so assuming you have those, here are two more places to start (in addition to the Park Tool blog posted above)

Cone adjustment: https://www.sheldonbrown.com/cone-adjustment.html

Hub overhaul: https://www.sheldonbrown.com/tooltips/hubs.html

Iride01 

Where are you measuring the millimeter or two? If out at the wheel rim then that might not be an issue.

andrewclaus

That much play is significant. Any play at all will eventually lead to bearing damage. For a decent mechanic with the right tools and supplies, it's easy to service and rebuild. But the failure is not typically violent or dangerous, so if you don't care much about the bike or it's not very valuable, and it's not important for your next paycheck, just keep riding it.

Bill Kapaun

IF it's a cup & cone type, tightening the QR tighter will remove slack.

KerryIrons

Actually, for lower-end hubs it is often impossible to eliminate play without there being some binding in the bearings. It is better to avoid the binding and have a bit of play than the other way around.

UniChris

A tiny bit, but this is probably more than needed - it's probably not loose from wear, but from the cones and locknuts having backed off together over the years.

I'd take it apart, clean, inspect/feel the cups and cones and at least regrease if not replace the balls (most likely 1/4" and readily replaced).

Even if one is going to ride pitted cones or cups into the ground, there's undoubtably a better compromise of rotational freedom and little (but not zero) play possible.

And it will be better clean with new grease than as is.

TPL

Contact Performance and ask them what sized cartridge bearing fits their hub on that wheel,

1989Pre 

I did. They identified the sealed, cartridge bearings and told me they no longer have them in stock.

1989Pre 

I don't know how "low-end" these are. They have sealed cartridge bearings.

1989Pre 

The Terramax wheel from Forte https://www.performancebike.com/fort...AaAi6sEALw_wcB has sealed-bearing cartridge hubs. I don't know how to adjust them. Performance does not stock them.

andrewclaus

If you really want to try to rebuild it, pull bearing(s) with a proper tool, or take the risk of damaging the hub by using an improper one (that's what I do). There are probably numbers on the bearing. Search for a replacement bearing, probably pretty cheap from a machine supplier somewhere--buy a few. Installing with a homemade press, made from threaded rod, washers, and wrench sockets, is generally easier than removal.

Andrew R Stewart 

My mistake on the hub bearing. I didn't google the bike model or the wheel and assumed that the bike is a lower end one then it turns out to be.

Most cartridge bearings used in bicycle hub applications are of a radial; contact design. These are not meant to be adjustable and are designed with some amount of float. For the longest bearing life the preload should be such that the inner and outer races are centered WRT each other. This is often done with good tolerancing in the machining of the shell and support sleeve (be that a separate sleeve or shoulders turned on the axle that the inner race seats against) or sometimes thin shims. A very few hubs (Suzie/SunTour) had the inner race sit on a threaded carrier that could be moved along the axle and trapped in place with a lock nut. The Sutherland's Manual (6th eddition page 10-8, scan attached) shows this stuff in easy to understand form.

Most cartridge bearings are available from various industrial suppliers and some consumer focused bike parts suppliers. Usually a bearing will have the spec number molderd onto the sealing ring or etched on the race. Most bike used cartridge bearings are dimensioned with the metric system. As example, a common rear hub bearing is a 6001 (2 RS, meaning two "rubber" seals). This bearing is dimensioned as 12x28x8 or 12mm ID, 28MM OD and 8mm thick. Andy

wrk101

Typically, a sealed cartridge bearing can be easily found at bearing supply shops or eBay (cheapest option). I can typically buy a tube of ten bearings via eBay for less than the price of ONE bearing. Bearings usually have a number on them.

1989Pre 

Thanks. I didn't know that bearings are generic and interchangeable. I had assumed they were proprietary. Cool. I'm going to bring it to the L.B.S.

1989Pre 

Thanks, Andrew R. Stewart.. This gives me an idea of the specs I am looking for.

sweeks

Maybe not as much slack as the OP is describing...

Bill Kapaun

"I can wiggle the wheel side-to-side and there is play at the bearings. Not much, maybe a millimeter or two."

OP isn't describing enough for you to quote me on saying it isn't.
If they are ham handed enough, they can probably make the wheel bind.

sweeks

I *did* say "maybe".

Andrew R Stewart 

The problem I have with considering the QR bearing preload addition is that I suspect the looseness is felt with a QR that is as tight as needed to keep the wheel in place. If so than more QR preload is not IME the best way forward.

Of course if the bearing slop is being felt with the wheel out of the frame the added QR induced preload will reduce/eliminate/go too far the slop. I don't think that's what the OP was describing.

As I sort of mentioned loose bearings rarely happen in a day's ride, or very quickly (excepting causes like a broken axle). The time/miles to have a otherwise good working bearing develop slop is a long/large number. We humans tend to think that our awareness of a problem is when the issue started (and in a way it is, if the problem is that we now have to do something about the issue). This is a poor way of looking at the world and how we understand interactions.

The time it takes from when an issue first starts and when we discover it has costs. Like pitted bearing surfaces, cracked hub shell cups, broken axles or just cones and lock nuts that migrate along the axle so no future fix is stable without real in depth assessments and repairs. Andy

sweeks

this ^^

Bill Kapaun

When in doubt, one should simply service the hub and know for sure if something is messed up.
That's absolutely one of the 1st things I do when acquiring a bike. Inspect/clean/lube the rotating parts if of a "serviceable" type.
If it didn't need it, it'll still be longer before it needs it again, so it's not a total waste. The cost/benefit of it being a "wise decision" outweighs the downside IMO.

Bike Gremlin

What I do is:
1) Use decent quality bearing balls, tossing out the factory-installed ones. That helps a bit to make the hub spin a bit less roughly when adjusted for no play.

2) Set for no play, even if it doesn't turn perfectly smoothly.

Using this method, hubs last for years without any wear (the oldest I keep a track of is now about a decade old and is being used).

I leave a tad of play only when the cones are already pitted - that seems to prevent them from wearing out even more, even faster.

Haven't tried adjusting the new low-end hubs for a bit of play. Maybe they'd last very long with that setup as well. Maybe not.

1989Pre 

SurferRosa, I have over ten posts? I'm so excited! Now I can post photos!
You really think I should invest in an adjustable wrench?
So I am looking for a "kind of a cone"?