Greasing Head Bearings - The Easy Way

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Greasing Head Bearings - The Easy Way

Post by Tirpitz »

This is one job I guess gets skipped at services with eventual unwelcome effects on handling and longevity of bearings. Never ceases to amaze me how people will shell out £100s on go-faster bits yet don't maintain the front and rear suspension and bearings. You can't go fast on a bike that handles like a coracle. So here's the quick and easy way to clean and regrease those headstock bearings.

We're assuming that the bearings are found to be in good order and don't need replacing. If they do you're gonna have to strip the front end anyway. But if all they need is freshening up with grease this will get the job done with the minimum of dismantling.

You need to get a bike jack under the sump. One of the type like this
is ideal as you can adjust the cups either side of the exhaust to sit on the sump edges and avoid removing it. Another way is to suspend the bike from a ceiling but TBH a jack is better as you can move it up and down easier. You want the rear of the bike on a paddock stand for stability. You need the tank off and the airbox scoop off (latter gives you more room to swing tools) plus the nosecone stay (ditto).

With the bike still sitting on the front wheel take off the headstock nut - 36mm socket and probably a breaker bar. A 36mm socket is a big one - if you're struggling to find one look under impact driver sockets. As long as it is a socket drive (probably 1/2 inch) you can use it with any socket set as well as a rattle gun. Loosen the top yoke clamps and remove the bolts underneath the yoke that attach to the clipons. You will not be able to lift the top yoke off because there is a security lug on the ignition barrel and removing the barrel from the yoke is also a PITA due to the type of fixings used. So you need to fiddle, more of which in a bit.......

Now wiggle the top yoke up as far as you can - it will go a short way - and then with a C-spanner or a drift turn the headstock lockring anticlockwise as far as you can get it to go until it butts up to the yoke. Now jack up the front of the bike a little - not too far as you don't want the wheel / forks dropping like a stone. With a wooden mallet hit the headstock spindle to knock it down a bit (or a piece of wood over the spindle and a hammer). You'll then be able to wiggle the top yoke a bit higher and turn the locknut a bit more. Continue like this, jacking up a little at a time, and soon you'll reach the end of the threads on the locknut so you need turn no further. You can now continue jacking up and knocking the spindle through until it suddenly drops clear revealing the bottom bearings. Remember, don't jack up too far, you only want to be able to get at the bearings and you don't want everything dropping out miles.

With the spindle dropped down you'll now be able to wiggle the top yoke free and push it forward to get at the top bearing. Remove the locknut and its pawl washer and you will be able to poke the roller bearing out. Beware, there is an o-ring on top of it which you need to put back in. Clean all the old grease out of the bearing and race and refresh. Do the same with the bottom bearing and race.

Putting it back together is the reverse of the above. It's a good idea to lower the bike down to get the bottom bearing seated, get the top bearing in and just start the locknut on its thread. You'll then have to fiddle about a bit jacking to wiggle the top yoke back onto the headstock spindle and forks. Once you've got it on you can drop the front of the bike down to ensure the bottom bearing is seated then you need to turn / drift the locknut round until the headstock is tight again. When you think you're there you'll need to jack up again to check - the front should turn lightly from side to side, you should not be able to feel the bearings grinding and the action should not feel restricted and tight. Grab the forks from the front and see if you can rattle them backwards and forwards. There should be NO loose play, everything should be firm with the forks or headstock appearing to flex. When you're happy that you're nice and firm you can knock the top joke right back down onto the clipons replace the bolts and reclamp to the forks. Finally, torque up the headstock nut to 54Nm.

Job done!
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Mori Man
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Re: Greasing Head Bearings - The Easy Way

Post by Mori Man »

Bought one of those jacks a few years back - 1st job I done with it , it paid for itself - invaluable tool :smt001

I actually bought it to put the USD conversion onto the ZRX , mine came with two support pads in different lengths but not that V shape as in your picture. You can also put a sturdy plank onto them and jack the bike up on the zorst (if it is strong enough) too.

Good write up BTW

MM! :smt001
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Re: Greasing Head Bearings - The Easy Way

Post by cargo »

On the race bike I use a couple of axle stands and support the bike on the a treat and the axles stands are handy for the van too

Also one axle stand makes for a handy side stand for the bike if need be
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Re: Greasing Head Bearings - The Easy Way

Post by Rasta-ninja »

Not sure if the OP was writing in regards to a H model... But if you have an L model you don't have to remove the stem to get the top yoke off. If you have the steering lock on that would be why the pin is sticking out and you'd need to go to and fro this way. As long as you have the steering all the way to the right the top yoke lifts up and over the stem first time :smt003

Sure you need to take them off to check the bearings anyways which was the whole point in the post but just thought I'd add this to save some time doing the job!
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