Model A - investigating the rear brake drum

 In common with several Ariels of this vintage, the Model A has a rear wheel sprocket which is integral with the brake drum. This in itself would not be a problem were it not for the fact that the sprocket teeth are worn out.

The whole assembly is far too big to go in my lathe so what can I do about removing the sprocket teeth? Some options:

• Can I spin the hub in the rotary table, mounted on the workmate and remove the teeth with a fixed angle grinder?
• Can I build a jig to carry the whole hub in the milling table, and remove the teeth with an end mill?
• Get Draganfly to do it?
• Find a local enthusiast with a bigger lathe?
• Find a better hub?

One thing I have discovered - a BSA A50 chain ring has the required 47 teeth to suit the 5/8" x 3/8" chain I need. An Ariel 4305-32 looks similar.

We'll have to think about that a bit more. In the meantime, we'll have a look at all the other bits in that area so that we can work out what we are dealing with especially since I'm expecting to place an order with the Ariel Klub Slovakia shortly. 

The brake plate is all present and correct.

The brake plate dust exclusion ring is a bit mangled - I have a feeling you can get these new as they are spot welded in place but since the 1930 Model A doesn't have a plated ring here I may repair it and paint it.

In the brake drum we have the 'new for 1929' ring that retains the spoke heads should they break off. Ariel must have had some incidents with brakes seizing or wheels grinding to a halt through loss of spoke heads. Not a pleasant experience to contemplate! It's all very greasy in there.

Equally greasy is the back of the brake plate but at least we have some shoes which are whole and a set of springs and a cam.

The cam bush is very worn indeed and will have to be replaced.

It's fitted through the brake plate and there is a nice little gas weld on the inside:

Here's the cam. I don't think there's any doubt that we will be buying new ones!

Something else that has caused much discussion on the Facebook group is what brake lever this machine should have. This part is definitely Ariel, but it may not be 1930 - however it's not much later, perhaps 32. Checking the parts lists doesn't reveal very much from any of these years - they all show a relatively short stubby brake lever. The various members that contributed to this discussion revealed quite a variety of brake levers including this long curved one - so go figure.

It did have a lot of bends in it. I've taken one out and this will probably sit better with respect to the mudguard stays - we'll have a look when it goes back together.

Moving on to the frame, we'll take the opportunity to clean out the threads for the chain adjusters

There's something odd here - this looks like a braze repair around the sidecar mount. The mounting should exist as a more or less complete ring without that lump of material between it and the frame lug.

The brake plate torque lug is present on the inside and both of the top hat washers are present.

Moving to the other side of the bike, this all looks good and the stand stops are in very good shape.

Missing from this side is the little flattened tube that's used to protect the wheel spindle thread from the chain adjuster. They are often mangled - we will have to make one of those. 

At both ends of the spindle, the wheel nuts are not in the best shape. The left hand side won't run all the way down the spindle - it looks like it's had a hammering at some time.

FH - tyres & brakes

 We're nearing the end now. I've got the tyres, tubes and rim tapes, the wheels are both built and the brake plates are stripped out. 

The plan was to fit the tyres myself so that I didn't have to have the bike off its wheels for too long, because I wanted to be able to develop the setting up of the brakes.

I started with the back wheel, trimming the spokes with a large half round file, fitting the rim tape and then the first bead of the tyre, making sure that the direction of rotation was correct. All went reasonably well. Next step is to put the tube in, so in the time-honoured fashion I put a bit of air into the tube and pushed it into the tyre. Getting the valve in through the rim and the rim tape was a bit of a hassle, but it's never an easy job. The next bit is to get the second bead on .

Fortunately I've had some large levers lying around for quite a long time for fitting tyres and these came in handy. Handy that is until the following day when I went to blow the tyre up and of course I had nipped a tube.

B*****. Just save any further messing about, I decided to do what I usually do and take the wheels to SPS Services in Horsford to fit the tyres for me, but first I needed to order a new tube .

While I waited for the tube I engaged myself in some more domestic duties, putting up some coat hooks and repairing the chainsaw which we had attempted to use to trim some damson trees at the allotment. I found poor crankshaft oil seals in the chainsaw and remarkably a run out of just under a millimetre in the crankshaft - and consider how small a chainsaw crankshaft is!

I sent the brake shoes to Villiers Services as usual for re-lining. I had asked for them to be riveted as well as glued, but Steve at Villiers Services explained that they had bad experience with Ariel brake shoes cracking around the rivet holes and didn't want to do it. I accepted the shoes with no rivets.

A few days later the new tube turned up and we made a rapid trip to Horsford to drop off the tyres and wheels and to buy an apple tree, scones and a cup of coffee or two on the way home. 

I was back there the next morning picking up the wheels with the tyres fitted and properly centralised. I have found it very difficult in the past to get the tyres concentric to the wheels, but these are perfect and fitted in the right direction.

They were back on the bike with the brake plates rebuilt and fitted by the evening.

FH - starting on the brakes

 Now that we are waiting for the tyres and we have the rear mudguard off, we can have a look at the rear brake. For reference, here's the drawing from the parts book:

First glance suggests everything is in order. The springs are all in place and don't look distorted at all; the adjuster is there with the two little mushrooms; there are no cracks in the shoes or the plate.

The shoes look old; they are worn, but not down to the rivets, but they look a bit greasy and glazed. This is the leading shoe:

This is the trailing shoe:

The drum is starting to see wear from being recently wheeled around and used a little:

I'm going to clean these up and see what the engagement looks like using the sandpaper technique. That will let me explore the adjustment and remove any greasy deposits to see if I can improve the performance before I commit to relining the shoes.

I've documented how I do this before, but it's essentially a long strip of 60 grit emery tape stuck to the brake drum with double sided tape. You then back off the adjuster, refit the brake plate and the wheel spindle, and spin the brake plate in the drum.

You then apply the brake with the lever so that the shoes contact the emery. The result is that the linings are reduced in the areas where they are high and this improves the fit of the lining against the drum. In this case, the exercise showed that the linings were already a good fit against the drum, but were clearly rather glazed.

We'll do the same at the front, and test ride it again.