Wheel bearing install - How did I screw up?? | GTAMotorcycle.com

Wheel bearing install - How did I screw up??

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timtune

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Front wheel 1972 CB750:
Heated one side of the hub, greased the bearing and tapped it into the hub. Felt it hit bottom and gave it a couple more shots to be sure. Was driving it with a large socket that only connected the outer race. While it was warm I greased the slotted aluminum adjustment/locking collar and spun it in. Used a blunt punch to tap it home and then a couple more taps.
Flipped the wheel, slid the axle in from one side, used it to center the weird 3 pronged bearing spacer with the next bearing. Then drove the second bearing in. (first side went so easily I didn't heat the other side - it did not take much effort to drive the second bearing in)
Felt the second bearing "meet" the spacer and gave it a few more taps to be sure.
Everything looks fine, EXCEPT now it's real bugger to get the axle in. It will only go all the way with a tap from a rubber mallet. From each side I can slide the axle in past the first bearing and into the spacer but then I hang up on the second bearing. Again I can do that from either side.
Tried a second axle thinking maybe it was bent a bit but it hangs up too.
All I can think is one bearing is slightly cocked.
Thoughts or suggestions??
 
The 3 prong side of the spacer goes to the speedo drive side - it should 'float' a little wee bit.
If you put it in backwards it's likely hung up on the bearing and causing the problem you describe.
 
TK4 said:
The 3 prong side of the spacer goes to the speedo drive side - it should 'float' a little wee bit.
If you put it in backwards it's likely hung up on the bearing and causing the problem you describe.
Click to expand...
The spacer has 3 prongs on each end - #8 below
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Now what? Pull them out and start again? Only to have the same thing reoccur...???
 
timtune said:
Now what? Pull them out and start again? Only to have the same thing reoccur...???
Click to expand...
I'm afraid so. Seat the first bearing, then insert the spacer making certain that the little tabs are in the spaces between the balls. Then start the second bearing, but before it is fully seated rotate the inner race to make sure those tabs are lined up as well. Once all that is done, drive the second bearing home. You may find upon disassembly that you've bent one or more of those tabs, fix them first.
 
OH FAK! I used sealed bearings with no place for those tabs. Now wait do the tabs actually extend beyond the tubular center part of the collar??

I guess it's coming apart to find out...
 
timtune said:
OH FAK! I used sealed bearings with no place for those tabs. Now wait do the tabs actually extend beyond the tubular center part of the collar??

I guess it's coming apart to find out...
Click to expand...
Light bulb moment !!! Just bust the tabs off, you'll be fine. (y)
 
Not to point out the obvious, but you're going to damage the bearing pulling them back out. You have no way of pressing them out using the outer race.
 
Renboy said:
Not to point out the obvious, but you're going to damage the bearing pulling them back out. You have no way of pressing them out using the outer race.
Click to expand...
50+ year old hub, I'm betting they'll come out pretty easy.
 
I think #8 is a spanner bushing (keeps the axle from tension from distorting the wheel bearings), the tabs are only there to make it easier to thread the axle. You can lose either the tabs or inner bearing seal without hurting the bike.
 
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I don't think the tabs have anything to do with the problem at hand. I think the bearings are misaligned. Whether that's due to a distorted hub or a piece of debris stopping one of them from seating properly, no idea.

Does the axle and both bearings spin nicely once installed? How about once clamped in place with the axle torqued?
 
Brian P said:
I don't think the tabs have anything to do with the problem at hand. I think the bearings are misaligned. Whether that's due to a distorted hub or a piece of debris stopping one of them from seating properly, no idea.

Does the axle and both bearings spin nicely once installed? How about once clamped in place with the axle torqued?
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No. The axle does not spin nicely. I'm also of the opinion that one bearing is misaligned. How the eff that happened???
I'm going to check with my verniers today to see if I can measure any misalignment between bearing surface and hub.
 
Brian P said:
I don't think the tabs have anything to do with the problem at hand. I think the bearings are misaligned. Whether that's due to a distorted hub or a piece of debris stopping one of them from seating properly, no idea.

Does the axle and both bearings spin nicely once installed? How about once clamped in place with the axle torqued?
Click to expand...
That style of bearing comes open, with seals(2RS), or shields (ZZ). The tabs on a spanner bushing (#8) only work on open bearings (#22) as the tabs seat in the space between balls. There is no space when the bearing has shields or seals, the tabs will work like a brake for a few revolutions, then shred the rubber seal clogging up the bearing.

Most aftermarket bearings for wheels are regular bearings with seals(2RS). There are 2 options:you can pluck the seal out of the bearing -or- bend or remove the alignment tabs from the spanner bushing.

I’d pluck the seal and seat the tabs. Makes reassembling the axle much easier.
 
The spacer, #8, is used to set the gap between the inner races of the bearing, the gap for the outer race is held by the hub. The "ears" on the #8 spacer is to locate the spacer in the center of the hub, so that it doesn't fall out of alignment with the bearings, so you can easily install the axle. Those two gaps have to be the same to align the inner and outer races so they're parallel.
The ONLY way to have bearing mis-alignment is if the bearings are canted in the hub.
I would remove one bearing, install the axle and spacer and see if the far bearing lines up.
If the holes where the bearings sit are worn, and the bearing doesn't press in snugly, the hub is junk (I have a couple of Honda CB hubs if you want them)

Mike: you cannot have something intrude INTO the bearing cage, the balls have to be able to move/circulate around the races... that's how roller bearings work, the roller elements have to roll.
 
bitzz said:
)

Mike: you cannot have something intrude INTO the bearing cage, the balls have to be able to move/circulate around the races... that's how roller bearings work, the roller elements have to roll.
Click to expand...
Since the fingers locate in the cages on both sides, the cages can move as long as they rotate at the same rate as the one at the other end of the axle.
 
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The spacer between bearings is clamped by the axle between the two bearings and thus locked in position to the inner races - in this case, held stopped while the outer race spins with the wheel (and the ball and ball cage orbit at an intermediate speed).

I can see what Mad Mike is saying if the tabs in question extend over the outer lip of the inner race into the gap where the seal would reside, but not far enough in to get into the path of the balls. I've never seen this design and I don't understand why it would be done this way, but whatever, it's conceivable, from the modern perspective they had some funny ideas in the old days. If that's the case then I still don't understand why it would restrict the axle from going straight through. The bearings have to be misaligned.
 
bitzz said:
I would remove one bearing, install the axle and spacer and see if the far bearing lines up.
Click to expand...
That's the thing driving me nuts. I used the axle to align the spacer and second bearing when installing it. I could not do this for money....
 
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