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Removal of steering head bearing


Guzzirider

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I am fitting new steering head bearings to the cafe racer, and have got stuck on removing the lower bearing from the stem.

 

The outer race containing the bearings came off easily, but the inner race is well and truly stuck. I've tried applying some heat with a chefs torch, and brute force but neither approach has worked.

 

Any top tips before I give it up and take it to a mechanic?!

 

Cheers

 

Guy

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take it to your local bike shop. They'll have a bairing clap and a 10 ton press. It will pop the thing right off. Then with the right piece of tubing it will press the new one on to the stearing stem and away you go.

 

 

Ciao

Z

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apply a cutting disc in a small angle grinder across the race carefull not to hit stem or triple tree and when almost through place a small cold chisel in the cut rest it on something solid and give it a hit I've done this on everything from axle bearing to head stem's and never had a problem. Handy when you don't have a press. ps sometimes you have to make two cuts :lol:

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when you are reinstalling;, freezing the bearings, wrapped in air tight plastic helps, along with heat where the bearings are going.Of course, a press is handy too. You can also do a quick-freeze using butane from a lighter refill cartridge.

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when you are reinstalling;, freezing the bearings, wrapped in air tight plastic helps, along with heat where the bearings are going.Of course, a press is handy too. You can also do a quick-freeze using butane from a lighter refill cartridge.

 

 

I don't want to be picky but heating expands and cooling contracts so throw the headstem in the freezer and warm the bearing to say 80-100c in the oven and you will find they almost fall together :D

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Gday Guy,

 

Ummm, are you a confident, capable welder / have adequate welding equip?

 

Clean out the old grease from inside the steering head and square away your work area, removing all flammable items - including your fuel tank...

 

Three small beads of weld ( say 12, 4 and 8 o'clock) approx 25mm long around the middle of the race (i.e. where the bearings run)

will contract the race as it cools and it will literally fall out...

I have done this several times with the upper and lower outer races on all sorts of bikes and it will work every time.

Done carefully, you will not even discolour the frame paint as it is fairly intense but short term, localised heat (vs heat guns etc)

MIG is best for this but careful use of a stick will do the trick.

 

Take care not to weld the race to the steering head - don't laugh - seen it happen... and take all the usual fire and safety precautions.

 

Read again the first line and answer yourself honestly...

 

Cheers

mud

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I don't want to be picky but heating expands and cooling contracts so throw the headstem in the freezer and warm the bearing to say 80-100c in the oven and you will find they almost fall together :D

 

By "fall together" you mean "by the gravitational attraction found at the surface of a neutron star" right? :nerd:

 

Heating the headstock makes the hole bigger; chilling the bearing makes the circumference smaller. Doing it your way is a recipe for disappointment.

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when you are reinstalling;, freezing the bearings, wrapped in air tight plastic helps, along with heat where the bearings are going(the stem).Of course, a press is handy too. You can also do a quick-freeze using butane from a lighter refill cartridge.

 

This would work great for the outer race in the steering head.

 

For the inner race (on the stem), you'll want to shrink the stem diameter (freeze) and increase the race diameter (heat)

 

 

Here's a simple race removal tool. Maybe someone on your side of the pond has something similar available?

 

http://www.pitposse.com/ststberare.html

 

I'm thinking that this tool is for removing the outer race, from inside the steering head. He's talking about the inner race, on the stem.

 

I use a Dremmel tool with a cutting wheel to cut through about 80% of the inner race at 2 opposing places, then smack it with a cold steel chisel. It'l split off clean. Be careful to not touch the stem or lower triple with the cutting wheel or chisel.

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By "fall together" you mean "by the gravitational attraction found at the surface of a neutron star" right? :nerd:

 

Heating the headstock makes the hole bigger; chilling the bearing makes the circumference smaller. Doing it your way is a recipe for disappointment.

 

read again I said the headstem not the headstock you know the tube that runs from the lower triple clamp to the top one. And yes if you sit the bottom triple clamp on the ground with the stem pointing straight up and dropped the bearing from the top of the stem it will more than likely slide straight on useing this method :D ps putting the races into the headstock I just use socket or an old race against the new one and tap in with a hammer making sure to work around it to keep it sqaure

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read again I said the headstem not the headstock you know the tube that runs from the lower triple clamp to the top one. And yes if you sit the bottom triple clamp on the ground with the stem pointing straight up and dropped the bearing from the top of the stem it will more than likely slide straight on useing this method :D ps putting the races into the headstock I just use socket or an old race against the new one and tap in with a hammer making sure to work around it to keep it sqaure

 

My bad: "steering stem" is the phrase I'm used to for that part, from hanging out w/ those sweaty bicyclists no doubt... ;)

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