replacing wheel bearings

[Lawrence]

The Haynes workshop manual suggests that, in order to change out the wheel bearings, the wheel should be heated to about 200 degrees f.  It further says the brake rotors should be removed to prevent their damage.  I'm wondering about that.  Would it really damage the rotors if the wheel where, for instance, placed on an electric hot plate to heat it?  And what about the actual extraction of the bearing?  Is this a challenging job requiring special skill and tools?  I've never done this job before, but I've read elsewhere that the bearings in some wheels simply drop out when the wheel is properly heated.

[mjydrafter]

Heating and cooling is not needed, but it will make it easier.

I did not remove the discs or use heat when I changed out my bearings this spring.

Most challenging part is getting past the spacer between the bearings, but past that it's pretty simple.

Have you ever changed bearings in anything else?

[Lawrence]

No, I've never changed bearings in anything that I recall.  That's why I thought it better to consult the forum. 
I'm puzzled by your comment re: getting past the spacer.  The wheel is off the bike now.  Looking at it, it would seem that I extract (one way or another) the bearing from one side, then flip the wheel over and do the same thing with the bearing on the other side.  Why is the spacer going to be a problem? Each bearing looks like it should be pulled out from its respective side of the wheel.

[mjydrafter]

No, I've never changed bearings in anything that I recall.  That's why I thought it better to consult the forum. 
I'm puzzled by your comment re: getting past the spacer.  The wheel is off the bike now.  Looking at it, it would seem that I extract (one way or another) the bearing from one side, then flip the wheel over and do the same thing with the bearing on the other side.  Why is the spacer going to be a problem? Each bearing looks like it should be pulled out from its respective side of the wheel.

Well, yes that is how it comes apart.  The bearings are press fitted into the hub/wheel.  The spacer keeps the bearings properly spaced between the ends of the forks on the axle.

If you have a blind bearing puller set and a slidehammer its cake...  I don't though, and I'm a cerified tool slut. :yes

Other wise you need to push the old bearings out from the opposite side.  Which will require moving the spacer out of the way.  Insert the punch or a long tool and bend the spacer out of the way, then use a long punch to knock out the bearing.  The second one is simple, once the spacer & 1st bearing are out.

Reassemble reverse of removal (I love that line...) :hehehe

Be careful to drive the new bearings in around the outside circumference with a proper bearing driver or appropriately sized large socket.  Don't forget to put the spacer back.

[racinrich]

I did not remove rotors.make sure when you set new bearings do left first ,be sure to press in only driving in on outer race , install spacer then press rt in ,check abs sensor for proper gap after done

[Lawrence]

Not having a bearing puller in the workshop and not warming to the idea of bending the spacer, I decided to have the bearings installed by a proper mechanic in the local shop.  Suffered sticker shock when I picked up the wheel.  :yow
For the charge I paid for labor, I can buy a bearing puller kit -- which I will do.  One job and its paid for itself!

[Scott_]

I think the idea behind removing the brake rotors was not from damage by heat, as they can get over 200deg when braking anyway, but by removing them you reduce the risk of damage just from handling the wheel when working with it.
The new bearings also can go in a little easier if you put them in the freezer overnight.

[Bob T]

For the charge I paid for labor, I can buy a bearing puller kit -- which I will do.  One job and its paid for itself!

What puller kit did you get?  Brand, model or even a link would be appreciated.

[TimTyler]

...not warming to the idea of bending the spacer,...

I think the spacer is designed to be bent.

[racinrich]

true spacer has minimal effect on outcome,a real mechanic has inside bearing pullers and fyi heat is not necessary.the germans have a heat fetish,they want everything hot for car applications also.

[pallum]

The bearings set onto a register machined in the wheels themselves and don't bear on the spacer. I used the handle to my 2 ton jack to bend the spacer enough to sit a small drift on the inside race of one of the bearings and drive it out evenly. Put spacer aside, flipped wheel over and tapped out the other bearing, all the while supporting the wheel and tire on two 4x4s. I heated the hub with the brake rotors and tire still attached until I just felt like it was hot and had the bearings sitting on ice in a cooler (took it to a Best Buy where my friend works in the audio install bay and they have a heat gun I could use), the first bearing dropped in most of the way, and a bit of tapping around the outside race brought it down to the register. Flipped the wheel over again, put the spacer inside without unbending it to make life easier next time I need to change them, and tapped the other bearing in until it hit the register also.

In my mind the spacer is only there to keep water from entering the axle area so I just loaded up the axle spacers with grease where they meet the wheel bearings and called it good. 5k miles and no problems, YMMV

[Lawrence]

Bob, that bearing puller kit is on the "to do" list.  I figure if I do the bearings on another 30-old bike I have it will have earned its keep.  I plan to keep an eye on the Harbor Freight sales flyers, the shade tree mechanic's friend.