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Front Hub eating bearings
#1
Greetings,

I have an Avaya 27" wheel. On one side of the hub, the bearings were pushed out.

I purchased a new set of bearings for both sides (the kind that come in a casing, not loose), greased everything up and made thumb tight. One side, I couldn't even tighten/loosen, which wasn't an issue.

Maybe a month later, both sides are now pushed out, the bearings/casing is bent, making it unable to put the seal back on, and the wheel wobbles probably within 1/2" each way. I obviously made a mistake somewhere, but I'm not sure where.... possibilities:
-I used a needle-nose pliers instead of a cone wrench
-bearings came loose (doubtful, they're in a case and I was careful)
-I used plumber's grease
-Overtighened/undertightened?
-Put the wheel on backwards?

Any advice is appreciated. The bike is on it's last legs, so to speak.

Pics from both sides.. sorry about the quality, it's all I have.
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#2
By "casing" do you mean a caged bearing, where there's just a frame to hold the balls in place, or a cartridge bearing that is totally enclosed so that you can't see the balls? The fact that you mention using grease leads me to believe it's the former.If it is a caged bearing then not using a cone wrench is the most likely cause of your problem. It is not possible for balls or the retainer to "come out" without the cone and locknut unscrewing first.

Look up "overhaul hub bearing" for the proper procedure, and make sure you inspect the cones and cups first for damage. If the cone is pitted or unevenly worn it needs to be replaced. Any damage to the cups means the wheel or hub needs to be replaced.

Also, what is "thumb tight?" If you mean hand-tight that is definitely not tight enough. Again, need a cone wrench

I won't go into the possible problem if a cartridge bearing unless you indicate that's what you have.
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#3
Hard to see what's up from the pictures, but here's a few ideas:
- If the ball bearings themselves are coming out, either you have the cone (axle parts) way too loose or you maybe used the wrong size bearing.
- If it is just the bearing holder that is tearing up and that pushed the dust cover out, you could have installed the bearings backwards or had the cones too lose. Or it could be that the cone and/or cups (the two surfaces the bearings roll on) are very torn up and this destroyed the bearings.
- Plumber's grease is not the right thing for this, but I doubt it caused the problem. Basic auto bearing grease works fine, water-proof trailer bearing grease is better. Or any standard bike bearing grease.
- Putting the wheel "backwards" wouldn't do anything. The front wheel can go either way.
- What went wrong would be nice to know, but isn't that critical to fix it.

You need to:
1. Take apart the hub again and inspect the cones and cups for damage. Replace if needed.
2. Get new bearings. Loose balls are preferable, but the kind in retainers will work. (You can fit one more ball per side with loose bearings so the load is spread out better.)
3. Make sure you're getting the bearings in the right way
4. Make sure you're adjusting the cone and lock nut correctly. It is possible to do this without a cone wrench, but it's a lot harder. The simple idea is that the cone should be as loose as possible, but where there is zero side-to-side play in the bearings AFTER you tighten down the lock nut. Simple theory, but it takes a little practice to get this right. Having the cones significantly too tight or loose will eat up the bearings very quickly.
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#4
Thanks for the input so far. I think I probably need new hubs/cones, but I'll check it out (bike is from '89).

The original bearings were loose, but the LBS gave me caged bearings to replace them with. By the time I had actually gotten around to replacing it, all but 3 of the bearings had fallen out, there was wobble, and a screeching/grinding.

RE: tightness, I used the pliers to tighten originally, but it was too tight, so I opted to just use my hand... need to get my hands on a cone wrench.

At this point, the cage itself has become somewhat mangled and won't lie flat, so I'll need to pick up some more.

I'm kind of torn with what to do w/ the bike in general. It's an old Panasonic... wheels probably need new hubs, a couple spokes, and probably truing and the bike itself needs new cassettes, chain, brakes, even the derailleur is cracked. But I'm broke, only ride it 5 mi/day on flat, paved roads, and am not much of a mechanic... so I'm just trying to keep it going.
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#5
Sounds like a lost cause to me - you're talking about approaching $100 in parts alone, definitely over $75, unless you can find a bike co-op with used parts nearby.
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#6
(08-27-2014, 07:51 PM)cny-man Wrote:  Sounds like a lost cause to me

Maybe, maybe not.
You need a new hub if the cups (the bearing race inside the hub) are pitted. If they're OK, new cones, bearings, and a couple spokes should do it. If they are damaged, you can get a whole wheel for $30.

To fix everything up nice and new may be more than it's worth to spend. But you can likely make it functional for not too much. A good way to learn a few basic repairs as well.

BTW - the bearing cages don't do anything except make it slightly easier to install the bearings. Leave them out. You can get one more ball in the hub without them and there's no issue of putting them in backwards.
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#7
(08-27-2014, 07:43 PM)PlumForgot Wrote:  wheels probably need new hubs,

a couple spokes, and probably truing

bike itself needs new cassettes, chain, brakes,

even the derailleur is cracked.

Maybe not, but it sounds like the bike is likely to "nickel and dime" (as in $5 and $10) him even poorer.
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#8
Plum; where are you located? Some of us may have parts that will keep you on the road.
Nigel
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#9
Hi guys,

Thanks for the advice so far.

I haven't been able to take it apart and clean it yet (primarily because I've been using it), but I did adjust it a bit and tighten it up. It tends to get "caught" at the same location each rotation, so I don't think that's a good sign.

I agree that it's probably not worth a full overhaul. I can deal w/ the gears by just using the gears I don't use as often and lower acceleration. The derailleur is cracked, but it works. The brakes work enough. On top of all that, the bike is a tad small for me and I may be moving in 6 months. However, I agree that the knowledge gained would be great and I just need it functioning. I'm not racing or putting even 50 miles/week on it.

I'm in Tampa, FL. We used to have a co-op, but it recently closed down. I believe I can get access to some legit tools, but parts are still an issue. There's a bike ministry not too far that I may be able to score some parts/knowledge from, but their parts come from donations, which would mostly be 5 year old magnas and other walmart bikes (not that I can be picky)... plus, I'd feel kind of guilty because I would basically be delaying a bike to someone that was referred there.
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#10
I finally got down and dirty and dismantled everything, cleaned it up and had a look.

Here are my thoughts:
-I definitely need new cones. The "tops" (narrow portion) of the current cones on both sides come up at about a 20 degree angle, as opposed to lying perpendicular to the axle.
-I wouldn't describe the cups as "pitted" (surprisingly); however there is 1 "pit" on one side where something must have dug in briefly. I am unsure if that is too much.
-The axle has all sorts of dents and ruts on the middle portion, but isn't bent
-The keyed washer should be replaced, as it had become mostly bent/flattened at the keyed portion.

So, some new cones, maybe a washer, and some bearings should be enough, hopefully.
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#11
-The only part of the cones that is functionally important is the cone shaped part.
-One pit is more than sufficient to cause problems.
-Nothing else on the axle is important if it is straight, the proper length and threads are OK.
- Keyed washer does not necessarily need to be replaced, just important to *use a cone wrench* when adjusting to prevent strain on the tab and to get proper tightening.
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#12
10-4 to what has been said. If the caged bearings became loose the nuts were not tightened against each other properly and came loose. There are two nuts on each side. They should be tightened till there is no wobble in the wheel and the wheel turns freely, than the lock nuts tightened while you hold the inner set nut from spinning. Test spin again.

Check to inner hub races for smoothness if slightly rough you may be able to smooth them with 400 grit sandpaper in circular motion. Not too much. Finding correct cones may be a challenge. Also instead of using caged bearings put loose bearings in holding them in place with heavy grease.(boat trailer bearing grease is good) This way you can get more bearings in. They should be 1/8". IIRC 9 per side. BTW a new sealed bearing wheel can be had for under $50 if you look around. Make sure the hub width is the same.

http://www.velomine.com/index.php?main_page=product_info&products_id=739

What model Panasonic do you have? Some of them were excellent bikes. Panasonic made the Schwinn Super le Tour in the late 70's early 80's.
Never Give Up!!!
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#13
Correction to the above - front hubs almost all take 3/16 inch bearings, not 1/8." You are best trying to get a cones (or an axle set) locally, as several dimensions have to match. take your old parts in with you.
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#14
10-4 for typical front bearings being 3/16 . Brain fart.

I rebuild the wheels on my 85 Fuji del Ray and spend a lot of time looking for cones. So many different threads and sizes. Next time I will just get new wheels, as parts are NLA.

Yes do bring your parts with you ,including the bearings. Getting a complete axle with cones new nuts etc may be easier way to go. ANND as I suggested go with loose not caged bearings.

Something like this, but correct size for your bike.

http://www.ebay.com/itm/Bicycle-Skewer-Axle-Qucik-Release-Front-M9-/221053267469?pt=Cycling_Parts_Accessories&hash=item3377cd2e0d

BTW if you leave your bike outside bolt on axle is more theft proof.


http://www.amazon.com/Wheel-Master-Front-Axle-Bolt-/dp/B0063R27Y6/
Never Give Up!!!
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