Help Needed: Off centered HUB

Unicycles and Equipment
1

Hello

I’ve searched the forum for problems like this and haven’t found any. I searched for:

“off center hub”, “misaligned hub” and got no problem similar to mine.

If there is another thread like this, sorry.

So here it is:

My hub is off centered and so the tire is closer to the frame on one side than the other and the same goes for the cranks.

How can I fix this? How much do you think this affects riding? I normally have a slight idea of off centeredness while riding. But end up adjusting my seat, so I don’t know.

Thanks!

Photos bellow:

2

Your wheel is out of true, you need to true it.

Search for wheel truing or take it to your local bike shop (often abreviated as LBS) and have them do it.

3

So that’s the name. Out of true! Hahaha, it’s funny.

OK!

Thank you very much, going to search!

4

The bearing on the left side (first pic) slipped out a bit, its not hte wheel that is out of true.

5

I forgot to mention. But the distance from wheel to the frame is constant.

For what I understood, truing it is not what I have.

The wheel is trued. Its just the hub that is off centered.

6

That small gap of shinny metal between the bearings and the spokes in the top picture is where the problem is I think. My nimbus 29er doesn’t have that. The bearing shouldn’t be up against the crank like that. Will the bearing come off if you remove the crank?

Both sides of mine look like the second picture.

Sorry I can’t be of more help. Has UDC seen these pics?

edit: yeah, if the distance to frame is constant the wheel is probably true. That bearing is where the problem is.

7

Ha! You where of great help! All this time I thought it should look like the first picture!

I see, the ball bearing is way off I think it has to go in. Damn. I hate removing the cranks!

Haven’t talked to them because I bought this unicycle second hand.

Thanks all of you.

Now, what is the safest way of fixing this? :slight_smile:

8

remove the crank and find a metal tube that will slide over the axle and touches only the inner metal ring of the bearing (try a seatpost). Gently tap the bearing back in to place with a hammer. If the problem reoccurs try some bearing sleeve retainer on there.

9

If one bearing is in the right place, against the axle spacer, and the other is way off and not against the correct spacer then doesn’t that show that the bearing holders in the frame are wider apart than the bearings? This could either mean that the frame has ‘spread’, meaning that the legs have bent away from each other, or the bearings were never spaced correctly.

To get the wheel to centre properly the bearings will both need to be spaced the same distance from the hub. It may be that you need to put a new axle spacer on each side of the axle between the hub and bearings.

Hope this helps.

10

Normally when mounting the frame on the bearings, I have to open the frame, and force it to enter the bearings. I’m new to this, and so it didn’t seem odd, but now I see the problem.

Thanks! Going to try it today!

11

Done! Let’s see if it stays fix.

Thank you guys for your help!

Hop on and away! :slight_smile:

PS: How do I change the topic title to: “SOLVED” or something?

Here are some photos of the doing.

The material I use to remove ISIS cranks.

I always waste a 0,02 euro coin in the doing. Because my crank remover is too thin and goes all the way inside the hub center hole.

I used a Shimano remover thingy to hammer down the ball bearings.

I hammered them both using a plastic hammer and an old sock boingboing*

Here they are, all the way in.

And here is the wheel all nice and centered.

12

Nice work! My bearings popped out like that because I didn’t have spacers in between the bearings and cranks.

13

What are spacers, and where can I get them? :slight_smile:

Now that I think of it. Wasting money might be a crime :astonished:

There goes inflation! :x

14

If you pound on a bearing again, be sure to use piece of pipe or something (I’ve used a deep socket) that has an opening larger than the axle, but almost as small so the pounding force is to the bearing’s inner sleeve. From the picture it looks like that Shimano tool pounded the soft sidewall of the bearing, could damage the bearing.

I expect things are fine, since the bearing was loose enought to slip over, glad you fixed things. Good luck with that ride.

15

Yes, the picture may elude, but I checked before pounding and it was pushing the inner part of the bearing.

That is very important, thank you.

16

Glad to hear you thought of it.

17

a spacer is a sleeve that fits on the axle between the crank and the bearing to keep the bearing in place. You can usually make them by cutting down the end of a seatpost. Not sure how well it would work as ISIS cranks are tapered and therefore will move on the axle more as they wear.

18

Is there any problem with the bearing slipping or the wheel being off center. My trials is like that but I never thought it was a big enough deal to fix it. Should I try and fix it or will it be ok if I just leave it alone.

19

I noticed a little off balance in my 29er. It makes sense physically speaking eventhough it was only half a centimeter. But haven’t tried it yet after the fix, so I don’t know if it is only psicological.

It was not hard at all to fix, but if you feel like it may do more worse than good, and if as you say you don’t notice anything strange, maybe it’s better to leave it like that. Ha, great advice here:x

Cheers

20

Rui, in this case the problem was in your bearing apparently. It could also have been in your wheel itself like you assumed initially. If the wheel is not wobbling but it is biased towards one side, that is not called “out of true” as one poster said. It is called that your wheel is dished. There exists also a condition as in your thread title, which is when the hub is off-centre. That would be that if you ride, you go up and down because the hub is not in the centre of the rim in a sideways view. All three conditions are corrected through spoke tensioning, but the procedures are of course different (and you don’t need to know now because your problem is solved anyway).

Your crank extractor is not of the right type for an ISIS hub. There are special ISIS crank extractors with a bigger ‘foot’. But if you only lose one 0.02 Euro coin every time you extract a crank, and there is no other problem (like still damaging the inner thread, or being involved in the criminal act of destroying money:)), an ISIS extractor won’t pay itself back for a l-o-o-o-o-o-ng time. And maybe you could even re-use the bent coin…