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Discussion Starter #1
I've just put new bearings in my front wheel as they felt rough when I pulled the wheel out for a tyre change.
But when the new bearings have closed up on the spacer tube they are now stiff as fook and barely turn by hand.
I thought of pulling them back a bit, but since the puller hook on the central ring I was concerned this wouldn't be a good idea.

Can I ask for advice on what to do or try?

Thanks
 

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I have not changed wheel bearings on my 1190 but have on many other bikes. Please forgive the questions but I don't know if you are a good wheel bearing installer or not, it's easy to side load without realising, trust me.. I know from experience. :censored:

How loose was the inner spacer once you'd installed the bearings, or are you saying you've already side loaded them and so they are already too tight to put back on the bike?

The other thing is did you install the bearings in the correct order as one generally gets seated against the hub whilst the other seats against the spacer. Get that wrong and the wheel could be slightly offset when remounted.
 

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Discussion Starter #3
My bearing installing experience is fairly low to be honest, done a few here and there.

I drifted in the bearing that seats against the hub first, then installed the spacer tube and drifted the other bearing down to meet the it. I suspect from what you say that I have put too much pressure on that second bearing?

I haven't got as far as putting on the bike as the bearings didn't turn easily, I just swore a lot LOL
 

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If it feels tight now then it's likely side loaded. You could drive one bearing out now and replace it, or try to loosen it a little by tapping the spacer bearing outwards. Heat the hub around that bearing with a heat gun and give that bearing a few taps, not hard but enough to shift it very slightly. If you're lucky it'll move out without pitting the shells, nothing to lose now so it's what I'd do.

I read the instructions that one of the bearing kits brands give and they state to just drive in the final bearing until it touches the spacer. That seemed to work ok but the best advice I was given was to flip the sockets around that I was using to drive them in with (assuming they are flat backed sockets).
Put the flat of the socket against the bearings (each side) and drive it on the more open side. The flat back of the socket will effectively lock the inner & outer shells together so you can drive them firmly against the spacer without fear of side loading. You could also get a proper bearing driver kit as that does the same thing, it's a solid disk so it drives both the inner & outer shells as one.
 

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Never hit the inner race installing bearings. If you don't have a socket that clears the inner race and catches the outer race, use the old bearing outer race by cutting a slit with a grinder and removing it.
You're half right. Yes you can install a bearing by driving only the outer race, and that will work fine for the first bearing as that seats with it's outer shell against the hub, but unless you are very careful you will side load both the bearings as you seat the opposite one against the spacer.

There is a reason that bearing driver kits use solid flat disks as driver ends, and it's not because they are too cheap to machine the inner out. Even though the driver end (or socket flat) can contact both the inner and outer shell, the inner is free to sag so it is actually just the outer shell that is being driven. Once the inner makes contact with the spacer it then resists the driver to stop it from driving the outer shell in any further. At that point the bearing has seated properly and you should stop driving it.

Driving it by just the outer shell means you have to guess when the inner is close enough to the spacer, which is resting on the inner shell of the other side so will now be sagging slightly due to the weight of the spacer resting on it. There is a lot of guess work involved to get it right doing it like that. Much better to use solid driving disks on both sides so the whole thing is locked solid when the bearings are properly seated.
 

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You're half right. Yes you can install a bearing by driving only the outer race, and that will work fine for the first bearing as that seats with it's outer shell against the hub, but unless you are very careful you will side load both the bearings as you seat the opposite one against the spacer.

There is a reason that bearing driver kits use solid flat disks as driver ends, and it's not because they are too cheap to machine the inner out. Even though the driver end (or socket flat) can contact both the inner and outer shell, the inner is free to sag so it is actually just the outer shell that is being driven. Once the inner makes contact with the spacer it then resists the driver to stop it from driving the outer shell in any further. At that point the bearing has seated properly and you should stop driving it.

Driving it by just the outer shell means you have to guess when the inner is close enough to the spacer, which is resting on the inner shell of the other side so will now be sagging slightly due to the weight of the spacer resting on it. There is a lot of guess work involved to get it right doing it like that. Much better to use solid driving disks on both sides so the whole thing is locked solid when the bearings are properly seated.
Sorry Mate, You are wrong. The bearings inner and outer races on a wheel bearing are perfectly aligned, the bearing recesses and inner spacer are perfectly aligned, once the outer races are seated the spacers tube is also seated to inner races with equal force and distance.

You should never hit any roller bearings in with any force on the inner race because it will fook the bearing, pressing a bearing in with the correct shoe is completely different. Technical non plain roller bearings often are supplied with the correct shoe or seating tool for a press. Some bearings cannot be installed without the correct tool. The problem here is the use of a socket and hammer technique, fine if done right....most often wrong. One inicent tap can damage a bearing giving it a shortened life.

If what you are saying is a true situation, that both bearings do not seat perfectly in the hub with the spacer perfectly aligned in perfect equal spacing between inner races, then the hub would drift. This is a mistake Ive seen where the wrong sized or damaged spacer is used.
 

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Sorry Mate, You are wrong. The bearings inner and outer races on a wheel bearing are perfectly aligned, the bearing recesses and inner spacer are perfectly aligned, once the outer races are seated the spacers tube is also seated to inner races with equal force and distance.
There is no information regarding wheel bearing replacement procedure in the 1190 repair manual so I cannot confirm or deny that.
I can see in the 990 manual that it is as you have described. The hubs & spacers are (I guess) machined accurately enough that you simply drive in each bearing until it stops.
This is NOT the case on most motorcycle hubs. With my trail bikes (previous one being a KLX300 and current is a DRZ400) one bearing is driven to sit tight up against the hub, the other stops when it contacts the spacer. If it is driven any further it side loads both bearings.

You should never hit any roller bearings in with any force on the inner race because it will fook the bearing,
I agree.. and as I have already said, using a solid disk is driving just the outer shell, the inner will sag. The inner only contacts the driving disk when it also contacts the spacer and thus stops all further movement of both shells.

If what you are saying is a true situation, that both bearings do not seat perfectly in the hub with the spacer perfectly aligned in perfect equal spacing between inner races, then the hub would drift. This is a mistake Ive seen where the wrong sized or damaged spacer is used.
That is not what I have said.
The first bearing seats to a specified position. The second bearing stops when it has snugged up against the spacer. The hub does not drift as it is how it was designed to be. You only have a potential problem if you seat the wrong bearing first as you will have slightly offset the hub.
The advantage of this hub design (as used on most if not all Jap bikes) is that it will be much less sensitive to spacer compression.
The weakness of the design on the 990 is that if the spacer shortens for any reason (could be wear, damage or compression of the alloy..) the bearing will be side loaded when you torque the axle nut and the bearings will die prematurely.

ledwardio said that after installing the new bearings the hub is now very tight.
This suggests to me that the new bearings are now side loaded.
If this is correct then there are only two reason for that. Either the hub on the 1190 is the type where only one bearing has an absolute seating position, and so one bearing has likely been driven too far in... or the hub is as on the 990's and somehow the spacer is now too long.
 

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There is no information regarding wheel bearing replacement procedure in the 1190 repair manual so I cannot confirm or deny that.
I can see in the 990 manual that it is as you have described. The hubs & spacers are (I guess) machined accurately enough that you simply drive in each bearing until it stops.
This is NOT the case on most motorcycle hubs. With my trail bikes (previous one being a KLX300 and current is a DRZ400) one bearing is driven to sit tight up against the hub, the other stops when it contacts the spacer. If it is driven any further it side loads both bearings.
Well Ive never seen that, I have seen bearings held by spring-clips to stop drift. I'd like to see a diagram. So what is the mechanics of stopping the wheel drifting?
 

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Well Ive never seen that, I have seen bearings held by spring-clips to stop drift. I'd like to see a diagram. So what is the mechanics of stopping the wheel drifting?
If you look at this diagram for the DRZ400 front hub you can just see it - the bearing on the RHS has a small gap between it and the hub.
The lower right diagram highlights the clearance.


Pg 143 explains the install procedure, sort of..
It assumes you are using the proper bearing installer set - P/N 09924-84521 (see link below).
The flat disks in this will ensure that the inner & out shells are locked together and thus the driving of the last bearing will stop when the inner shell touches the spacer.

 

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Discussion Starter #12
ledwardio said that after installing the new bearings the hub is now very tight.
This suggests to me that the new bearings are now side loaded.
If this is correct then there are only two reason for that. Either the hub on the 1190 is the type where only one bearing has an absolute seating position, and so one bearing has likely been driven too far in... or the hub is as on the 990's and somehow the spacer is now too long.
I believe this was the case as I was a bit stumped at first when initially looking at the side without the bearing seat and wondering how to know when to stop. As I was using the open end of a socket to drift as the socket narrowed too much towards the flat I think I have done as you say and put too much pressure on the outside ring.

For the cost of the bearings I think I'll pull them out and start again, with a steadier hand.
Going to invest in a proper drifting tool a well, is it something like this that you are referring too Trousersnake:
 

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Going to invest in a proper drifting tool a well, is it something like this that you are referring too Trousersnake:
That's the sort of set I'm going to buy soon as I need to stop pissing about with sockets to do this job. :giggle:
Only thing to check is that the set you buy actually has the right size collars for your bearings.
What size are the wheel bearings on the 1190's? (google isn't telling me).

Edit: It's a 6906 bearing according to Folwers so you'd need something like a 46mm collar ideally, that ebay kit won't do it.
 

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Discussion Starter #14
I quickly put a tape measure over it and its about 48mm but I'll double check before ordering anything, just wanted to check that I was looking at the right type of thing.
 

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If you look at this diagram for the DRZ400 front hub you can just see it - the bearing on the RHS has a small gap between it and the hub.
The lower right diagram highlights the clearance.


Pg 143 explains the install procedure, sort of..
It assumes you are using the proper bearing installer set - P/N 09924-84521 (see link below).
The flat disks in this will ensure that the inner & out shells are locked together and thus the driving of the last bearing will stop when the inner shell touches the spacer.

I stand corrected. There is a slight clearance, conclusion is you need to press the bearings in. I can see no mechanics stopping slight drift, I wonder why its designed like this.

Edit: I see, the design has a collar that fixes the outer spacer preventing the whole sandwich of spacers moving. Strange design....and this is the same on 1190?

I think this makes sense now, the inner and outer spacer must be finished to match the whole fork and wheel assembly? So indervidual to the bike and soaking up the lack of tolerances in the whole assembly?
 

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I quickly put a tape measure over it and its about 48mm but I'll double check before ordering anything, just wanted to check that I was looking at the right type of thing.
Do you have a something for the other side too?

The ideal way to install these would be two 46 mm disk/collars and some threaded rod (with nuts) to act as a puller.
You could drive the bearings in using a hammer but when driving the final bearing in the other side also needs to be fully supported (by the inner and outer shells), so you really need two 46 or 47mm collars, one for each side.

Edit: I suppose you could just use the soft contact method. Drive the last bearing in until it just kisses the spacer and stop there. If you do that you could just use the socket you used last time.
 

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Discussion Starter #17
There's a circlip on the outside of the bearing that meets the collar, I took it that this would hold this bearing in place while the other side and the spacer is fitted. You are probably right that a proper double-sided puller might be a more prudent purchase.

31988
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Yup, if you can find a couple of thick washers the right size then go for it.

You can drive the first bearing against the circlip to 'snug it home' as you're just pushing the outer shell against the circlip, the inner shell is hanging free. Doesn't that side have a seat though, so you'd drive the bearing against that?
You shouldn't drive the other bearing that way if you can avoid it.
Ideally both the bearings' inner & outer shells should be supported on a solid plate. If you do that they can't be harmed (within reason) so you can drive them together firmly.
If the inner on either side is able to move independently then that bearing can be damaged, in which case you should drive the final bearing in very carefully and stop as soon as it touches the spacer.
 
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