I guess that I have been shying away from looking at the girder forks for a while - it occurred to me that I have never dismantled a set of forks like these but having dived straight into it, it's dead easy.
The first job was to make sure the back of the bike was strapped tightly to the lift table and then use the scissor lift to raise the engine a bit. Then I gingerly loosened the front wheel in its clamp and confirmed that everything was stable.
Pulling the forks about revealed a lot of movement and I made a little video:
There you go - clearly a number of problems there.
Removing the spindles and replacing them with scrap round bar allowed me to have a look at the links. The part you would call the bottom yoke in a conventional telescopic fork is called the fork crown by Ariel, and the links attached to the crown at the bottom are pretty worn:
Both sides, as you can see. This means the links will need bushing or replacement; the top ones are worse.
Fortunately removing the crown and steering column revealed that indeed there were no balls in the steering head bearings, so that will account for a lot of the movement.
I will probably clean up this area and leave it in factory paint as it is in quite good condition.
The steering head races had two balls left in them. We will clean them up and see how worn they are.
Ariel call this bit the ball head clip - it carries the handlebars and the spindle for the top links. Said spindle was absolutely solid in the clip and I had to resort to the splendid Rothenberger Surefire 2 to warm the grease up and get it to move.
The spindle came out eventually - but look at the state of it. The bike has also been used with the spindles loose which has worn most of the thread away and part of the link too.
The main girder assembly looks pretty good:.
I'll repair these worn areas though - it looks like the mudguard has been loose and has fretted the fork leg. These will build up with weld.
Whilst the girder fork assembly is still a bit contaminated with old grease, I'm quite confident that the spindle bores are good enough.
I spent a while getting all cleaned off the next afternoon. The two races that fit into the frame are chipped but with new balls seem to work ok.
I'm going to replace the spring while I can. You remove these by tapping the end with a hammer and a punch to unwind them from their fixing spiral:
This is the lower fixing - the upper one is part of the main girder.
You can see that the spring has opened up - it must be quite soft.
I rebuilt the forks with the new balls in the steering head to determine how much play I had solely coming from wear in the links and spindles. With these old parts in place, the wheelbase varied 3/8".
I've been in discussion with the Black Ariel spares man for the AOMCC and have some new parts on the way.
Four days later and we are now over one hundred miles - there hasn't been any more smoke, and I have checked the points again which seem to be stable at 12 thou. I've backed the front brake off a notch and tightened up the back on the cable - they seem to be fine now, though the pedal is a little lower than I would like.
There's some oil mist on the drive side which appears as oil when the bike is on the sidestand - it drips from the head joint onto the primary case, though there are no other oil leaks. The head is going to have to be tightened down.
In other news, a mail to the splendid AOMCC gearbox man revealed that the kickstart was an after market one - it was harassing the back of my leg. In this picture, the one without the rubber fitted is the splendid new club one - you can see it is much less cranked:
It's a lot more comfortable when fitted.
As mentioned in the last post, I moved the gear lever up a notch only to find that it fouls the timing cover. The gearbox man confirmed it's the right one, so perhaps I well drop the footrest a bit lower to put my toe in the right place.
Riding today I heard a groan from the drive side - getting home revealed the primary chain was too tight and the rear chain too loose - easily adjusted. I'm sure the steering head could do with a bit less clearance too, though the judder from a few days ago is now a barely perceptible click.
Out and about on the Huntmaster again today shows that the steering head bearings are getting sorted. The handling is as good as ever, maybe a bit more sure on its feet and braking is very smooth - there is much less judder from the front forks - though it does need a little more adjustment.
Yesterday I checked the contact points and found in both positions that there was a dragging fit on a 12 thou feeler gauge. The bike started readily as usual this morning and ran very well on a 4 mile trip to Cromer.
There is conspicuous oil in the drive side silencer however I didn't notice any smoke. Is this a temporary problem that comes from leaning the bike over and dripping oil into one of the valve guides? Certainly it happens after parking on the side stand and of course the side stand causes the bike to lean towards the drive side. The oil in the exhaust could have come from the various smoke experiences I've had over the last few days. Am I clutching at straws? Is it just the rings bedding in?
The handlebar mirror is a little bit loose and needs nipping up, and the centre stand needs some oil on the pivots. Oh, and before I go, the gear lever needs to come up a notch!
After the last trip, back in the workshop, a quick check revealed the expected 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 centre 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:
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 the Square Four is on the bike lift 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.
This time, I had to loosen the handlebar clamp to get enough access to the stem nuts. 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 centre 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.
Another little ride out today - twenty miles around the local countryside:
Starting easily, it's running a lot less busily with it's raised gearing.
The brakes are feeling much better now - there's quite a lot of travel but they are certainly biting.
The steering head bearings are very loose - there's a lot of juddering on braking. There might be an oil leak from the cylinder head area - there's a drip on the front of the top of the primary case, coming from the barrel, and there's some oil at the back of the barrel.
It seems to be quite smoky on the drive side - I'll keep an eye on this.
Everything else seems to be working well though I think I can hear the ignition hardening up again so perhaps those points are closing up.
Next jobs are to secure the mudguards prior to temporarily fitting the wheels. First though, we have a few more bits from Draganfly - the fork top nut washers and the steering damper knob spring:
Then we need to fit the FERC, or Fully Enclosed Rear Chaincase in Ariel speak. It's a big floppy tin thing and is a bit of a struggle, but it goes on. You have to fit the rear sprocket and it's stub axle first:
That nut will get plated in the coming months, but I am not so sure if those washers are the correct outside diameter.
I'm hovering around fitting the gearbox but I need to clean it first. Before that can go in we can fit the oil filter on it's bracket - it's nut is a candidate for plating too:
The FERC looks tidy when it goes in; the smaller bolt in the outside of the lower half is a pig though, as it is hidden by the pillion footrest support.
You can most definitely get the oil filter out with the FERC in place!
The front part of the FERC must go in before the gearbox, and that needs the chain oil line:
The front half is retained by two screws to the frame above the swinging arm:
The oil line will need adjusting for length and some bends changing:
First I have to figure out which line to connect it to!
As you might have read, after a prompt from the guys on the AOMCC FB page I bought some new stanchions, and very nice they are too:
Build it right, build it once I say. Here are some pits in the old ones and they will destroy the seals very quickly:
These are the original seal holders - they are supposed to be shiny chrome, and someone has cut them shorter for some reason. They are junk now.
I bought these seal holders on eBay - they are plated steel, and are very solid. They came with a set of springs (not the nice progressive springs in the background) for £65, so I thought I had a bargain; the seals themselves are standard lip seals, about £5 a pair.
I put them together with a new set of Draganfly bushes.
During that build I found the first stumbling block: the seal holder tool didn’t fit in the holder.
I needed to turn the tool down by around 2 mm on the diameter. To get it in the lathe, I had to make a plug so I could steady the end with a centre. The tool is too big to go in the fixed steady.
So now I could put the forks together…
End plug and bottom bush:
Here’s the next problem, and it’s Game Over. One of the seal holders is fine, but this one has the thread out of square with the stanchion axis:
So, they were returned to the seller, and replaced with these from Draganfly. They are beautiful.
A few spare minutes found me progressing the build a bit further. Last night I ordered the engine parts from Draganfly; the pistons and big end shells have already arrived from the AOMCC Twin Spares chap. They look excellent:
The swinging arm goes in easily and is bolted very loosely. It's held up with an old shock.
I've put the steering damper back in; the pin tapped in easily.
Now, I was careful to ask the painter to avoid grit blasting the oil tank, and he has indeed prepared that by hand. However, the fork sliders would have benefitted from blanking off as they are full of grit; I made this swab to clean them out:
Running paraffin down the slider in the cleaning bath I swabbed the grit out:
There's quite a bit - that was worth doing:
I cleaned the fork legs with 180 grit Scotchbrite - they are not very good:
I ordered a set of seals and new seal holders yesterday. At £115 a pair, it's worth buying a new set of hard-chromed stanchions as well.
