Head Stem Bearings - things that I have learnt

[Plaz]

OK...there stuffed....no need to ask how. So I have to change them.
Now this being a smarter than average group I'm looking for those hints and tips on how to make it easier.

I know the basic how to, pulling the farings and whole front end off is no biggie. What I'm really after are those tricks you've learned from expirence.

Ill probably look at doing this at some stage over the weekend, so I thought I'd post it up now to get the smart arse repiles out of teh way by tomorow.

[smek]

gonna borrow your thread here plas...

I gotta do mine too so feel free to add more detail than was requested by plas
are they expensive?

[Plaz]

I got an after market from All Balls Racing Products, tappered roller bearings, to replace the Kawa cheap as bearing races. $90.00

[Smitty]

I got an after market from All Balls Racing Products, tappered roller bearings, to replace the Kawa cheap as bearing races. $90.00

...interesting
I bought a genuine set for the GeePeeX750 late last year
top and bottom taper bearings, races and seals..for about $85

and interesting that was the same price as from CBC

I rang around and most prices were the same for the 750


hth

[Smitty]

OK...there stuffed....no need to ask how. So I have to change them.
Now this being a smarter than average group I'm looking for those hints and tips on how to make it easier.

I know the basic how to, pulling the farings and whole front end off is no biggie. What I'm really after are those tricks you've learned from expirence.

Ill probably look at doing this at some stage over the weekend, so I thought I'd post it up now to get the smart arse repiles out of teh way by tomorow.

tricks?

LONG lengths of water pipe, 4lb hammer, an angle grinder and a welder

why?
welder?.. to put some metal blobs on inner races (pressed in headstem)
length of pipe/hammer? to hammer the farkers out
angle grinder?...to cut off bottom bearing from steering
(or use a VERY special bearing puller which goes over steering locks)

other than that?
a very secure stand setup..you are gunna get physical
and the knowledge to pull apart/re-assemble a front end

final hint?
do a fork oil change while you are at it


hth

cheers

[Smitty]

the problem children in any headstem bearing change are indicated....
the rest basically comes out by hand

if the bottom bearing is a complete taper jobbie..you need the
angle grinder (or press plate)

the 9 or 12 don't use a tapered bearing so its only the race thats
gotta come out..and all the ones I have done...are stubborn

hth

[Gosling1]

...LONG lengths of water pipe, 4lb hammer, an angle grinder and a welder...

and a cold chisel. thats it.

The top bearing will be easy to remove, and generally the top *cup* ( the bit in the steering head), has a small lip that extends into the steering head.......when you use a drift ( the water pipe) through the steering head from underneath, you can catch the edge of the lip, and hammer it out from underneath, slowly, moving around the lip so you do it 'evenly'. Replacing the top cup is easy, I use a piece of hardwood as the 'drift', place the cup in the steering head, and hammer in gently, holding the timber drift as 'flat' as possible on the top of the cup. The top race should just press onto the steering stem without any drama. Top race gets removed first, and replaced last.

The lower *cup* is a bitch. As Yoda says, run a small bead of weld with a stick (electric) welder, say 10mm, on opposite sides of the cup. This will give you a *lip*, that you place the drift on, through the steering head from the top side. (Depending on the bike, you may need to build up the bead higher, so the drift can get a good 'purchase'.) Give it a couple of gentle taps on each bead, and it should just about fall out (the welding will heat up the lower cup and this helps it dislodge.)

The lower tapered race is also a bitch - because they are an interference fit on the steering stem, an angle-grinder is the fastest, simplest way to get the bastards off. Two words......BE CAREFUL - you don't wanna go grinding through the steering stem Once you have ground through the outer race, this should have out enough heat into the whole assembly, so that a cold chisel *should* be able to 'assist' the bearing up the stem and off.....once again, just work around the race evenly.

Good luck. The water pipe can also be used to drift the lower race onto the steering stem, if it is the right diameter ( ie, *just* enough to fit over the steering stem, and bear on the inner of the lower race.)

A bit long-winded, but its a fair old job this one....

[Neilp]

put the new taped races in the freezer, this will shrink them enough to make it easier to install.


Neil

[Plaz]

I knew you guy would come up with gold. Thanks a heap, useful tips all!

When we did Greeny's Butter Knife (it doesn't really qualify as a FireBlade) I used a dremel tool with a cutting disc on the lower seat. Cut a couple of notches, and tapped (read belted the shit out of) it around evenly. It felt much safer than using a full size grinder.
The only hiccup we had was that we didn't have any water pipe to use to put the new seat on, So a quick trip to JMD (local bike wreckers) and a borrow of their hydrolic press 2 mins later it was on.

[aardvark]

...LONG lengths of water pipe, 4lb hammer, an angle grinder and a welder...

and a cold chisel. thats it.

Surely there's something better to listen to whilst working on bikes?

[Smitty]

...LONG lengths of water pipe, 4lb hammer, an angle grinder and a welder...

and a cold chisel. thats it.

Surely there's something better to listen to whilst working on bikes?

oh...oh, Jase no like 'Khe San'

so howzabout The Angels...or The 'Oils

[Gosling1]

....Surely there's something better to listen to whilst working on bikes?....

no way, Four Walls, Wash Basin, Prison Bed......takes me back to Bathurst '85 every time

....so howzabout The Angels...or The 'Oils ...

Now your talkin' Am I Ever Gonna See Your Face Again ? (nowaygetfuckedfuckoff)

Oils - mostest favourite band for quality bike-spannerin' time there is. I just loaded the *entire* Oils cattledog onto my i-Tunes library...

Good to see them get inducted into the Hall of Fame the other night......what an excellent band they were.

[FrogZ]

Only thing I see left out was to use the old cup as a drift/spacer to put the new one in.
Oh and dont drink until AFTER the job eh

[I-K]

Only thing I see left out was to use the old cup as a drift/spacer to put the new one in.

You know, I keep trying that every time I do a set of steering head bearings. After about the fifth time fetching the old race from across the shed, I give up and go back to my old trick of using a large plastic mallet as a drift; that has a handle so I can stop it from flying off when I smack it.

You got a trick for holding the old race in place when using it as a drift?

Meanwhile, my other trick isn't in there, either.

To remove the inner race on the bottom bearing, ie. the one pressed onto the steering stem, get the angle grinder and rather than try to grind right through the bearing race (steel vs underlying aluminium of the steering stem) to get it off, just grind a little notch in the race surface, perpendicular to the stem, then use that as a foothold for a drift (a two-foot screwdriver in my case) to smack the race off the stem.

[Plaz]

All good advise again.....except the music

I'll stick with my Pearl Jam thanks.

To remove the inner race on the bottom bearing, ie. the one pressed onto the steering stem, get the angle grinder and rather than try to grind right through the bearing race (steel vs underlying aluminium of the steering stem) to get it off, just grind a little notch in the race surface, perpendicular to the stem, then use that as a foothold for a drift (a two-foot screwdriver in my case) to smack the race off the stem.

Pretty much exactly the method we used with Greeny's bike, cheers.

Looks like this will be a job for next weekend now as theres now one avilable here to help me tie rope around the bike and hang it from the shed rafters to pull the front off.

SA guys exepct a call sometime this week