Stuck bearing races

[chunkolini]

I am just changing the head races on my Africa Twin.
What comedian fitted them? bone dry ;ubricated with a dust composed of rust and one mangled seal.
I have got everything apart except removing the fixed cups. Well and truly stuck. they only have a tiny lip to get any purchase on.
I have managed to grind a slit in the lower race with a diamond wheel in my dremel but it is still stuck.
WD40 on tonight, no plus gas available.
my drift is too short so I need longer and capable of inflicting accurate violence. And cant get to my workshop to make anything.
Our local tool shop is not much use for anything.
One thought is a length of round 10 or 12mm brigh tbar cut square at the end , I have a contact in town who can provide this.
What is next?

 

[Istayinalot]

You could try running a bead of weld around the face of the cup, let it cool , that should shrink the cup enough to get it to move.

 

[dobbslc]

Tack a weld onto it, as it cools it will contract and if you are quick a smack with a long screwdriver should shift it. Make sure you hit it at 180° intervals one side at a time so it doesn't jam up.

Edit ^ you beat me to it!

 

[Pete.]

Yep put an ally disc in the bottom so you don't weld the race to the headstock then run a bead round.

 

[chunkolini]

Problem is bike is at home in bits, work is ten miles away.

 

[Depaugie]

when you do manage to remove the old bearings,
it would be a good idea to fit a grease nipple to the yoke.
An occasional squirt of grease, it will keep the moisture out and that will be the end of your dry rot.

 

[octo0072000]

I bet the next time you do it will be at work not home

 

[Maker]

I'll start by saying I know nothing about motorbikes but if it's anything like a push bike, can you not split a piece of tubing and stretch it open a tad so it can be slid through the headstock, then spring open in order to catch the back of the race, then hammer it out? I can take a picture of what I mean if that makes no sense.

 

[Robotstar5]

The 10 or 12mm round bar used as a drift should work, although serious hammering is usually required to shift them.

 

[chunkolini]

I have considered doing it at work, but I done live there.
This adds to the excuses to have a cheapo welder at home.
I will pop top my mate's place in the morning and buy a few lengths of whatever has lying around.
They have probably been i there for twenty five years.

 

[CRB]

Even a chunk of wood might shift it.

?Do you have diesel available?

 

[chunkolini]

No diesel, I been and soaked them both in WD40 again.
Problem is the tiny lip, about 3mm.
A drift with a sharp right angle ought to, no Will do the job.
Grrrrrrr
Will do the job, loooking flyable in the afternoon

 

[CRB]

It is true, no tools, no job.

 

[Justme]

3mm is loads to get a drift on to.

 

[gordon stephenson]

As said 3mm is ample lip, could even use a strong screwdriver that you are not too fond of,

 

[Kent]

have you no portable welder? welding a shrink into races normally works a treat

 

[gordon stephenson]

Chunko does not have access to a welder where the bike is located,

 

[chunkolini]

Sorted, I got a length of 13mm bar cut by mate, gave the bottom race a good 'CRACK' and felt it move first time, a few minutes later it wass on the floor, the top one took a little bit longer, but no blood spilt.
I had lost the new races. Some fool had put them in the freezer.
Job done, coffee and then the wheel goes back in.
Then hopefully off to bung myself off a hill this afternoon.

 

[normspanners]

Chunko does not have access to a welder where the bike is located,

In the war----- I did it with a rod and a couple of batteries and jumperleads.

 

[chunkolini]

Took the bike out for a ride this afternoon and all seems fine, especially feet up at town traffic speeds, transformed.