Showing posts with label hub. Show all posts
Showing posts with label hub. Show all posts

Wednesday, 24 June 2026

Model A - front wheel

One of my key aims is to get the machine rolling so that I can get it off the bench when I need to, to get the others on the bench for servicing etc. To that end I sorted out headstock bearings and the wear in the forks, but of course we still have no tyres and the wheels are not fit to have tyres fitted.

I thought I would change away from my normal method of dismantling a wheel, involving bolt cutters, and see how feasible it was to dismantle it nipple by nipple. I sprayed each nipple with Plus-gas months ago and I was pleased to find them all come apart easily.


Before long I had a fully stripped hub and brake drum, a pile of loose spokes, nipples and a rather rusty rim - a WM1-20 which might get reused one day if I can ever buy tyres for it.


Despite worrying about whether I'd made the right decision with respect to the rusty nature of the rim, the spoke heads confirmed that rebuilding the wheel was a good thing to do. Several of the spoke heads are about to pull out of the hub:

After a short period of decreasing, scraping of general muck and abrasive removal of rust, I put on a coat of primer


Followed by a couple of coats of black gloss:

The black powder coated rims have been delivered from Devon along with spokes and nipples but we will need to wait something like 5 or 6 weeks for this paint to harden before we can build the wheel. More of that later!

Sunday, 7 December 2025

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.

Sunday, 16 March 2025

FH - front wheel

 A very short blog post just to record that I've finished building the front wheel. 

Of course the first step is to finish the polishing. Here it is with the 80 and 150 grits done:


I needed a break of a couple of hours to let my arms and shoulders recover from the strain of polishing - these hubs are quite heavy. Here it is fully finished:


With a bit of experience, you can build these up wheels very quickly. All the spokes are tight in this view but it's not quite true; I'll leave that for tomorrow.



Saturday, 15 March 2025

FH - wheel building

 With the hubs polished and the proper spokes delivered, we can start on the delightful job of lacing the wheels. 

These will use butted spokes like the originals fitted by Ariel back in the 1950s. The nipple end of the spoke is thinner than the head end - in this case the nipple end is 10 gauge and the head end, with perhaps 1" of spoke length is larger at 8 gauge. The idea is that the stressed part of the spoke is strong without making the wheel ridiculously heavy; this will have the effect of making the steering lighter by reducing the gyroscopic force on the wheel.


I'm building the wheels on a post which is of a suitable size to go through the wheel bearings. The bore of the bearings is 1"; the post I'm using is 1 1/8" so that the hub is happily suspended in mid-air. 

It's essential to get all of the spokes into their holes in the hub before you attempt to fit any of them through the holes in the rim. There is absolutely no chance of getting the spokes in the right place if you attempt to put some of them through the rim before they are all fitted in the hub, so be warned.

For this Ariel/BSA wheel Devon supply the rims in two packets - one for the inner and one for the outer spokes, that is the spokes whose heads are on the outside of the spoke flange but whose length is on the inside, and the converse for the outer spoke.

When polishing the hub I had used a brass brush in the Dremel to clean out the spoke holes. It was easy therefore to slip the spokes into place starting with the outer spokes. Because these hang down, it's a bit easier to do these first followed by the inner spokes.


You can see the butted spoke in this close-up:


Once you've got them all in you'll have this forest of stainless steel wire:


The next job is to offer up the rim. You have to decide which way the spokes are going to point -there is often a fret mark on the outer spoke flange which will show you how the originals fitted. I start with the outer spokes on the upper flange and follow the pattern shown in the spoke flange by the original spokes and fit three or four of the new spokes into their holes with their nipples screwed on by literally a couple of threads. These three or four spokes should all point in the same direction; then I will fit another one in the opposite direction still in the same flange which will serve to stabilize the rim. You can then carry on fitting the same spokes in the same flange until you have all the outer spokes fitted in the top flange. By this point you will have learned that for each outer spoke pointing in the same direction there are three holes in the rim until the next spoke of the same orientation.


When you've done that you can fit all the inner spokes from the top flange as well. This will enable you to ensure that all of the spokes cross in the proper orientation. Don't mix up the crossing, or you will end up with bent spokes.


You can then repeat the performance for the lower spoke flange but this time start with the inner spokes followed by the outer spokes, again to preserve the proper crossing.


Once you've got all the spokes in, you can do up the nipples gradually and evenly until the end of the spoke appears in the slot on the outside of the nipple, like this:


Now it's time to put your wheel in your truing jig or perhaps back in the bike. There's no substitute for using the bike frame as a jig to allow you to adjust the spokes so that the centre line of the wheel is aligned with the centre of the frame. This works beautifully on the Ariel swinging arm frame, but is much more difficult on the Square Four frame - because the Square Four frame is asymmetrical at the rear to accommodate the offset engine.


I made this spoke screwdriver years ago and it's very useful for tightening spokes when you can get to the nipple from the space usually occupied by a tyre. It makes it much quicker to tighten the spokes than using a spoke key.


I'm not going to explain the whole alignment process here because there are reams of material about it in this blog post, written when I was building the wheels for the Square Four. I must say though that these Devon rims and spokes pulled together to give a wheel that was virtually true and aligned out of the box.

Very nice indeed.


Now we just have to do it all again at the front!

Thursday, 6 March 2025

FH - polishing hubs

 I've started on the rear wheel for no particular reason other than I expect it to be more work and secondly it's easier to get out than the front one for which I need to remove the wheel stop on the bike lift. 

The first step is to take a wire brush to the sand cast aluminium surfaces on the inside of the spoke flanges. You don't want to scratch the outer polished faces because it will be the devil of a job to remove the scratches made by a steel wire brush.


For the outside I have used a combination of 180 grit Scotch-Brite pad and a degreaser. This reveals a nice groove which whilst it looks quite uniform has actually been worn in place by the sharp edges of the chain case. When it's clean you can see that the bottom of the groove is quite rough:


With the grease removed we start with the 80 grit stitched mop and polish out as much of the tarnish as we can. We will also polish the edges of the spoke flanges and the ribs around the drum.

This progresses through the 150 and 300 grit wheels to the polishing mops:


It doesn't take long before it's ready for lacing on the rim.


Shame I have ordered the wrong spokes. It's shown here sitting on a 1 1/8" post, clamped in the Workmate, turned to just under 1" to allow the hub to slip over it. We'll lace the wheel in that.


Thursday, 27 February 2025

FH - stripping the back wheel

 Finally, and it seems to have been a long time coming, it's time to start on the wheels. I've got the tyres now though I have had to compromise with a 90/90-19 front tyre rather than the 325-19 that I wanted, but at least I have everything.

It doesn't take very long to remove the rear wheel from these bikes despite the fact that I have complicated matters by fitting indicators, and these need to come off before the rear of the mudguard can be unbolted.

The first step is to measure the offset using a straight edge across the bearing housing. With that in place we can measure 7/8" to the edge of the rim.



These are quite common wheels so finding someone that could help with the lacing pattern of the spokes wouldn't be difficult. Nevertheless it is good practice to photograph your wheels before dismantling such that the peculiarities of the spoke pattern can be recorded for the rebuild to come. These Ariel full width hub wheels are simple in that the spokes are of two types - those that fit from the outside, and those that fit from the inside; this results in similar lengths but different head angles for the two types. For the half width hubs fitted to all my other Ariels, there are four types of spokes in each wheel.


When you have all the components delivered, and you have recorded your spoke pattern and your offset you can dismantle the wheel. I've done this a few times now and have discovered the quickest and easiest methods to my mind.

Let it be known that we are not going to reuse any of these components other than the hub. Therefore the best way to remove the rim is to cut through all of the spokes on both sides; I use a bolt cutter for this job which makes short work of snipping through each of the spokes.



There we go. The tyre has not even been deflated yet!


Here is the hub with the remains of the spokes. It's sensible to cut the spokes as near to the hub as possible because it is much more difficult to remove the full length of the spoke from the hole in the hub.


You will find most of those little bits of spoke are stuck in their holes through corrosion and dirt. Just wiggle them a bit to release the gunge, and thread them back through their holes.

Removal of the rim and tyre is equally brutal. All I have done here is to take a hacksaw to the tyre, lubricated with some WD40 and sawn through both the tire and part of the rim such that I can cut through both beads and the tyre will just fall off.

And that's it. Apart from a trip to the dump with this scrap metal and rubber the next job is to start polishing the hub.

Friday, 16 August 2013

Wheels again...

Work on the engine has stalled for a moment whilst we wait for FW Thornton to see if they can help out with a ring problem. The bench is now clear, so we can start on one of those other 'waiting in the wings' jobs that we use to fill in when the main workface stops for some reason. Bike building is like that - there is always something else you can do to fill in when waiting for parts.

And so to building the wheels. The 'jig' I use is just a piece of 19 mm ply that used to be part of a desk. The cutaway sections make it really easy to get to the nipples. It has a hole on the middle for the wheel spindle, which is a piece of 1/2" round bar. Using the spindle as a centre, I mark the outer diameter of the rim on the board. Using the offset measurements I made from the wheel earlier (before I stripped it) I make up four wooden blocks to lift the rim off the board to the correct offset. The brake drum, which I use as the datum, is placed face down on the board.
And that is it. There is a much more sophisticated version of this idea in Frank Farrington's excellent book 'The Vintage Motorcyclists Workshop' which includes blocks to control the concentricity of rim & hub - I don't go this far, since when rebuilding a wheel from an intact but rusty version I can buy spokes to exactly the right length and I find that I get very good concentricity by virtue of that spoke length.
So here we go. Set the hub up on the jig:


Add the blocks to establish the rim at the correct offset:


Start adding spokes according to your lacing pattern. You did photograph these wheels before you cut them apart didn't you? It helps if you lift the hub above the jig at this stage, so that you can insert the spokes from both sides. As you add the spokes, try to lay them out according to the lacing pattern. Start with half of the spokes on the lower flange, placing them in alternate holes, pointing in the anticlockwise direction (in the Ariel's case, these spokes have the nipples on the outside of the hub). Then, add the other spokes on the lower flange, pointing them clockwise and crossing the anticlockwise spokes according to the lacing pattern (in Amelia's case, these spokes are threaded from the inside out, have the heads on the inside of the hub, and cross under the anticlockwise spokes).


Then you move on to the spokes in the upper flange, again starting with the anticlockwise spokes. When you have finished, you will have this nice little nest of wire:


Next, lower the hub back on to the jig and lay the rim over the top. Look carefully at your reference photographs, paying close attention to the location of the holes in the dimples in the rim, and make sure you get the rim the right way up. You can easily assemble the whole wheel with the rim upside down, and not notice until you are snugging down the last of the nipples. I know - I have done it!


Now, again we must be careful and work to a pattern, but a slightly different pattern this time. We don't want to scratch that shiny new paint! Starting again with the spokes in the lower flange, and your handy lacing pattern, locate the dimple nearest the valve hole that corresponds with an anticlockwise spoke on the lower flange. Insert one of those spokes in that hole and screw a nipple on a couple of turns. Then, moving clockwise round the rim, insert all the anticlockwise spokes in the lower flange. Then, start on the anticlockwise spokes on the upper flange and continue until you have a nipple on all the upper & lower anticlockwise spokes.
The reason for doing it this way is twofold:
  1. Working on spokes that point in the same direction means that the wheel is very flexible, and you can rotate the rim to get the spokes in the holes without endangering the paint.
  2. Working on the upper and lower spokes in the same direction means that you cannot 'trap' the unfitted clockwise spokes whilst you fit the anticlockwise spokes. Because the clockwise spoke crossings are inside the anticlockwise spokes, they can't get stuck behind spokes that are already fitted.
Keep the nipples really loose to maintain flexibility - you are only trying to establish the lacing pattern and get the spokes in the right holes at the moment.
Next, fit the spokes pointing clockwise. Start at the from the valve hole, and fit the first spoke from the lower flange, followed by the first spoke from the upper flange. Moving clockwise around the rim, fit the spokes in turn - lower, upper, lower, upper - until you have all the nipples fitted.
Now, take the wheel off the jig and have a good look at it. Give it a shake. Make sure all those spokes are entering those holes easily - there should be no tension anywhere at this point. If you are happy, put the wheel on the jig and wind the nipples in until there are 3 threads showing, and repeat the look/shake process. You will probably need to use a screwdriver now, as the wheel will stiffen up.


Now, with the wheel back on the jig, wind the nipples in until there is no thread showing. As you do, make sure the spoke heads are seating properly in their countersinks. Look & shake again. Next step, run all the nipples down until the end of the spoke is level with the bottom of the screwdriver slot in the nipple; then go around again until the end of each spoke is level with the very end of the nipple - you will need a spanner or a spoke key this time. Off the jig again, you should find you have a very stiff wheel. If one or two of the spokes are still loose, snug them down now, as evenly as possible.
This gentle step by step approach to spoke fitting ensures that the wheel comes off the jig needing very little trueing up.

So next, trueing up.

Hopefully, having built the wheels on the jig, we will have very little truing to do. However, there is usually some runout, but the offset is probably good. By the way, the offset I measure from Amelia's original wheels was:
  • Rear 9/16" on the brake side
  • Front 1 1/4" on the brake side
Now, what is runout? There are two types of runout - lateral runout and radial runout, as illustrated by this handy picture I made:
Radial run out is, pretty obviously, an eccentricity of the rim relative to the hub. Lateral runout is when the axis of the rim is not parallel to the axis of the hub. Easier to explain with the pictures!

So, how to fix it? Well, you can do miracles with a spoke key, but first you have to figure out what is wrong. To establish this, you need to set the wheels up in a jig, like this:


This is made from two pieces of timber, glued and screwed to a cross member, held in the vice. There is a V-notch in each piece for the wheel spindle to rest in. At the bottom, adjacent to the rim, are two pins:

One is set up so it almost touches the side of the rim; the other so it almost touches the outermost edge of the rim. Spin the wheel in the jig, and you will be probably be able to see both lateral and radial runout. Move the wheel slowly, and you will be able to quantify the run out in both directions - it is essential to mark the rim where the runout is worst.

You'll want to get the runout down to 1 mm, or 1/32", in both radial & lateral directions. You've probably got about 3 mm or 1/8" now, right?

So the key to tackling runout is the proper adjustment of the spokes. Here's another of Simes' handy diagrams:

Ain't that pretty! A few words about it:
  • The dotted lines show the spokes on the non-brake side
  • The solid lines show spokes on the brake side
  • The 'upper half' and 'lower half' relate to positions on the wheel relative to a mark you will make on the rim during the truing process
  • The green spokes go ant-clockwise
  • The red spokes go clockwise
Tackle the radial runout first. Roll the wheel in the jig again, and  relative to your pointer, mark the rim where it has most runout, i.e. where it is lowest against the pointer, where the distance from the outside of the rim to the centre of the axle is greatest.

Roll the rim until that marked point is at the bottom, and now you will have  spokes in the lower half and spokes in the upper half. Because we have the worst runout at the bottom, the spokes in the lower half need to be shorter, and the spokes in the upper half need to be longer, to reduce the runout and make the rim concentric with the hub.

So, you must appreciate that the spokes which are more or less horizontal, and radiate from the extreme left and right of the hub don't have any effect on the runout. Conversely, those running vertically are controlling the runout and it is these that will be adjusted most. Those that run diagonally from the hub have more or less effect depending upon how vertical or horizontal they are.

So, using this diagram:


We can see that the spokes within the red arrows have more effect on the runout than those that are outside the arrows. To correct the runout, hold the wheel in the same position (with your mark at the bottom) and loosen the spokes within the red arrow at the top by, say, 1/4 turn. Loosen ALL the spokes within the arrow - the red, green, dotted and solid ones. Then tighten the ones at the bottom, within the arrow, by the same amounts.
When you have finished, measure the runout again. It should have reduced a little. Now  repeat the process until you are satisfied that you have minimised the runout.
Correcting lateral runout is a little more complicated. Remember:
So again, locate the point where the runout is worst, and mark it. In this case, 'worst' means the point where the BOTTOM of the rim is furthest to the RIGHT, like the diagram above.

To tackle this lateral runout, adjust the spokes in this sequence:
  1. Loosen the SOLID spokes in the lower half of the wheel by 1/4 turn
  2. Loosen the DOTTED spokes in the upper half of the wheel by 1/4 turn
  3. Tighten the DOTTED spokes in the lower half of the wheel by 1/4 turn
  4. Tighten the SOLID spokes in the upper half of the wheel by 1/4 turn
Here is the diagram again to remind you:



When you have finished, measure the runout again. It should have reduced a little. Now  repeat the process until you are satisfied that you have minimised the runout.

And that, ladies and gentlemen, is that. All that remains is to file off the protruding spoke heads:


File them flush with the nipple, so there is no danger of them popping a neat hole in your inner tube. Fit a nice new rim tape, put the tyre on and go and have a beer in the garden.