Showing posts with label head race. Show all posts
Showing posts with label head race. Show all posts

Monday, 16 June 2025

FH - back in action

 With the Square Four on the bench, the Huntmaster fixed and a trip for a job in Cromer in the offing it's time for a little bike ride. 

In preparation, I topped up the oil a couple of days ago as I had had the return system apart and expected the filter to be empty. I turned the engine over on the kickstarter with the plugs out in order to prove circulation before I used it again. 

After I'd finished my decorating job, I came back to the bike to find a little puddle under the rear chain case. I guessed there might be too much oil in the oil tank and so it proved: 

I filled the big syringe twice getting this back to an acceptable level. It's been off the road for a couple of weeks and obviously wet sumps! 

At the same time I adjusted the front brake and the head race bearings.


Saturday, 16 May 2015

A little trip to Cromer

An evening ride to Cromer revealed a front brake that was much better, but which now had too much lever movement. Nipping up the adjuster two clicks improved the lever movement and there didn't seem to be any brake binding, which was excellent. There was still a juddering from the front, particularly on braking. Getting it home, I found that wheeling the bike backwards revealed that particular groan that only binding brakes make, so I've backed the adjuster off one click.

Back in the workshop, a quick check revealed loosened head bearings - wheeling the bike forwards and putting the brake on reveals a 'jolt' from the headstock which you can hear. To check them more physically, put the bike on the main stand and put your thumb here in the dim & dark recesses of the top yoke, across the gap between the dust cover and the headstock:

The Engineer's Thumb

With your other hand, grasp the front wheel and rock the bike backwards. This has the effect of pushing the steering column up through the headstock against the weight of the bike, and your thumb will be able to feel any movement. Don't vigorously rock it backwards & forwards - you don't want it rolling off the stand.


Mr. Waller suggests lifting the weight off the front wheel to perform this job, bit since I have no bike lift or any desire to damage my back I use the method described above.

So, having found some movement we need to sort out the problem. First slacken off the lock nut under the top yoke with your head race spanner. Clay at Acme Stainless has these, but you can also pick original ones up on eBay. Be very careful not to damage the paint on the tank - make sure the spanner fits well (so that the spanner doesn't slip) and that the tank is protected (for when the spanner slips):


Now, grasping the wheel again, roll the bike backwards against the main stand whilst attempting to tighten the lower of the two nuts. You will find that the nut is now loose and can be tightened down - you will want to perform this feat of coordination two or three times.

When you are happy that the bearings are snug, and you can feel no more movement, tighten down the top nut. Move the handlebars and satisfy yourself that they are not binding anywhere. 

If you use your steering damper, reset it and you are good to go.

Saturday, 7 April 2012

Building up

So, a few shots of half an hour's work, putting in the yokes:

Bottom bearing greased...


Steering damper parts all assembled. All from Drags bar the star washer and centre stem which are original


Top bearing greased


Bottom yoke in & bearings adjusted.