Head Bearings

[top_beta]

The head bearings on my EVO need replacing but the inside shoulder of the top bearing is seized onto the shaft and will not budge ! We've tried hitting it with a hammer with a piece of wood inbetween to prevent damage, heating it and using a penetrating oil but it isn't going anywhere. And ideas as to where we can go from here ?

[dombush]

Two thoughts (assuming that you've checked there isn't any other more simple reason its not moving, this is quite unusual)

• Use an aluminium dolly instead of wood to transfer more of the shock load (wood is a good shock absorber)
  

if that doesn't work.....

• Get some local targeted heat onto the inner race of the bearing as the resulting expansion breaks the seizure, use some penetrating oil before it fully cools.
  

Dom

[guys]

If you can get to it with an angle grinder, just cut in in two but be careful not to damage the shaft.

[top_beta]

Thanks for the suggestions, I will try the aluminuim tomorrow ! I cant get either the bearings or the steering shaft connected to the bottom yoke out of the frame though due to the seisure, so heating the shaft is a tad risky !

[0007]

That is a very unusual thing

Generally that is a fairly loose fit and the stem usually just drops out of there with no effort

Can you post a picture of the stem ? Is there visible rust/corrosion between the bearing race and the stem?

[zerorev3rev4]

as already stated you need to heat inner race to expand it ,not the shaft as that will have the opposite effect to what you need

[0007]

I don't know, there is no compression fit on that bearing, it is not pressed onto the stem like the lower race

If compression/press fit is not the cause then thermal expansion would not be the solution

I spoke with a fellow who removed the top nut from the top triple clamp and thought the stem would pop out, didnt know there was a nut under the top clamp