Rule of Nine

Many moons ago, I had a burning interest in classic cars, many with British Motor Corporation 'A' Series engines. One of the useful tips I learned working on these was the Rule of Nine, a way to easily make sure your engine was in the correct position when adjusting valve clearances.

The thing is, when you adjust the clearance in a particular valve train you need to make sure the cam follower or tappet is on the base circle of the cam, or the clearance will be excessive. You do this by checking the clearance on both valves in a cylinder when that cylinder is at TDC. The thing is, wild valve timing or quietening ramps in the cam profile means you have to be accurate when positioning the engine.

But there is an easier way. Have a look at this camshaft:

That's a spare camshaft for my Square Four - a lot less worn than the one in the engine. On the right hand side of the picture, you see the thread retaining the cam chain sprocket, and that first cam is the exhaust cam for number one cylinder - notice it is pointing straight up and the valve will be fully open.

Here's a Stormy Petrel's eye view of the rockers, so you can see what I am talking about:

Move to the left hand end of the camshaft and we are looking at the last or eighth cam, the cam for the exhaust valve on number three. It's pointing straight down, which means the valve is fully closed and the tappet is on the base circle.

Now look at this picture. The cam that is pointing up is the inlet cam for number two cylinder - it's the fourth cam on the shaft.

The one pointing down is the fifth cam on the shaft, the inlet cam for number four cylinder, so

4 + 5 = 9

Remember the first example where we looked at the first cam and the eighth cam? Well:

1 + 8 = 9

Guess what? It works on the other valves too! So, if the valve on the second cam is fully open (which is very easy to discern) then you know that the valve on cam seven (the exhaust valve for number four) is on the base circle and can be adjusted.

Easy. The Rule of Nine.

By the way, I found that after 1000 miles, most of the clearances needed adjusting - maybe because I didn't do it very well last time.

Finish off with replacement of the rocker box gaskets with Threebond. The fibre gaskets specified by Ariel are not suitable for the sorts of temperatures the cylinder head sees.

Out & About on the W/NG

Near Aldborough, Norfolk.

A new day and a new project

So today is a new day: this morning, we hoisted my Bantam into the back of a van for it to start it's journey to a new home in Teeside:

A Bantam, waiting for a van

It's been a brilliant little bike, attracting a lot of attention and getting me back into a hobby which I love and which I had missed for almost 20 years. It started me off on this writing lark, lots of blog posts, magazine articles and the Bantam Restorer's Guide, if it ever gets published...

But what now? Time for the FH to come down from the loft. It's going to become my fast road bike, possibly replacing the Square Four. My thoughts are:

• Fully restored - it's in bits, in multiple colours, and several key items are missing. In short, it's got no patina.
• It's going to be finished in export paint colours, because I like that and because there are a lot of maroon Huntmasters out there
• I'm going to replace the rims with stainless, with stainless spokes and plated brass nipples - I thought about getting these built at CWC, and ask them to polish the hubs, but I'll probably build them myself as usual
• I'll use stainless fasteners throughout. I believe Ariel's of this vintage would have had zinc plated (and not phosphated) fasteners, so in view of the proximity of the sea, dull stainless is the way to go
• It's got a new Mk1 concentric already
• It's currently got a 2 into 1, though I have two silencers - I think I will keep the 2 into 1, at least for a while
• I'll tear the engine down before I decide what to do with it, but it will be rebuilt to standard specification
• The magneto will be rebuilt by Tony Cooper
• I need to get it built, inspected and dated to retain the original registration number. I'll do a dry build first.

To get moving, I am going to start with the frame and cycle parts. There is quite a lot of welding to do before we get to sending out for painting, so perhaps I will do this:

1. Strip the top end and timing side off the engine, to release the head, barrel and engine plates for the dry build and to release the magneto and dynamo for reconditioning.
2. Put the frame on the bench, and assemble the gear box and empty cases into it
3. Start welding the mudguards, chain guards and seat pan to trial fit tinwear and frame components
4. Dry build, with fasteners from stock and no engine internals, wiring or cables.
5. Register, photograph and develop the 'missing & broken parts' list
6. Send black items (cycle parts) out for powdercoat 
7. Send the wheels out for rebuild
8. Send the levers and handlebars out for plating
9. Send the tanks, toolbox, and mudguards out for paint
10. Start the engine and gearbox rebuild
11. Reassemble when it's all back...
12. Wiring and cables
13. Shakedown!

We'll see what happens!

Another Tommy Bar??

Hunting around for tools for the FH, I realised that I needed a tommy  bar to double as a tyre lever from the Ariel parts list, but I have no idea what it looks like as Ariel stopped illustrating their parts lists in 1951. Triumph used something like this:

 I needed to make one, as they were either very expensive when available or just not available. I could either start with a tyre lever and turn the end, or start with bar stock, turn it and forge it to shape. The second is undoubtedly the better approach, but I didn't fancy the forging element in my small workshop so I bought a ready made tyre lever:

I had to slim the spoon end down to get it in the hollow spindle on my lathe - one element which raises a question about my approach. I turned the plastic handle off to reveal as much plain shank as I needed for the screwdriver section.

Turning the end to suit the tommy bar holes in a typical box spanner was easy, as was grinding the screwdriver shape in the end:

The spoon end needed reshaping, and is still too thick:

Ariel Bikes

Here's an interesting web site on the Leader & Arrow - one I had not seen before:

https://arielbikes.wordpress.com/

Portable Power Supply

Some of you may know that I tinker around with solar power from time to time and that in fact my workshop is 'off-grid'. One of the features of a lifetime spent tinkering with stuff is a lot of spare bits lying around, so when a friend was looking for a lighting system for her allotment shed and summer house I thought I could come up with something quite easily.

I had a 86W panel and a small car battery knocking about (as you do - they were part of the evolution of my workshop solar power system), so I would not have to spend much money. I also had a simple panel controller, which essentially sense battery voltage & connects the panel if the voltage is below a set point and disconnects it when it goes above the set point - pretty basic; no MPPT here.

What I needed was something to unite it all into a simple portable unit. This came in the form of a bit of an old kitchen unit and some pine offcuts:

I used the little router to cut a slot at the back:

This accommodates the foot of the battery. I sized it to suit the largest battery I had, to 'future proof' it a little. You can see how the foot of the battery is trapped in the groove:

The other foot is trapped under this little bar, made from 3 mm cold rolled sheet and retained with two M6 wing nuts:

Here's the battery in place with the controller:

Here I've added a simple modified sine wave inverter. It gives 200 W at 220 VAC, so you can charge your phone from it.

Here it is with the wiring completed. The six terminals top left are for the solar panel and for two 12V outputs. Lower down, there is a higher current termination for main battery cable, voltage sensor and feed to the inverter.

The inverter provides 200W at 220 VAC - that's about an amp, which translates to about 20 A on the DC side; I can run a 60Ah battery for 36 minutes at that rate, assuming my maximum allowable discharge is 20% - with a deep cycle battery I could increase that, and the frame will carry larger batteries.

Charlie's Shed - Free the Nipple

We have to make a new set of cables for the W/NG's new handlebars, using the techniques shown in my Cable Making post here. Unfortunately, the lovely Czech levers I have appear to be a little under size for the clutch and brake cable nipples so we are going to need some non-standard nipples.

This presents yet another mini-lathe opportunity. Starting with a bit of brass (10 mm OD) we turn a suitable length to provide two nipples to provide an easy running fit in the lever - about 8.8 mm.

This done, we need to drill the holes. The inner cable diameter (for the clutch in this case) is about 2 mm, so we'll need a through hole for that and a shallow hole, maybe 5 mm, for the birds nest and solder bucket. We'll start with a centre drill, with the bare nipple in a tailpost V block:

The centre drill is followed by a through hole drilled 2 mm, and this is followed by a 5 mm hole to a depth of 5 mm for the 'birds nest' that we will form when we fit the cable.

Here's the bar after drilling for the first nipple:

The next job is to part off to the desired length, in this case 10 mm. The finish leaves alot to be desired - I was running the lathe too slow for brass.

Deburring next; notably the cable hole on the reverse of this picture. I use a centre drill to open that hole out a little to catch the open, unsoldered wire ends on the inner cable.

So that's it. I made three out of the bit of bar I had turned to size, to avoid wasting it. One for the front brake, one for the clutch and one for the box of nipples & ferrules. I wonder if I can make ferrules...

Haven't you done enough shaking down?

So another day, another road test. After the weekend, where I checked out the B5HS plugs (pale grey centres, all the same - as expected) and fixed a very dodgy crimp in the distributor circuit and filling the tank, I took an early evening bimble along the lovely A149 North Norfolk coast road, into the setting sun. As usual, the SQ4 was fine for the first few miles, though I thought a little more reluctant to rev from a closed throttle than normal. We stopped for a break and a picture at Blakeney:





There's a narrow lane down to the beach here, maybe 300 yards down a hill which you do at 20 mph or less - idling, essentially. At the T junction at the bottom, there was a reluctance to rev and I coaxed the bike to a parking place where I enriched the idle mixture half a turn thinking that it had been reluctant to come off the idle jet since leaving the house.

A few more miles, and once out on the open road again she was flying. A little stumble now and then but generally great, until I got to a little village called West Runton, which has a mile or so of descent down a narrow lane into the village centre - again, 20 mph max, throttle closed, followed by a short hop over a railway bridge. By the time I was at the bottom, opening the throttle would kill the engine and there was no way I was getting over that bridge until the engine had cleared its throat. Once on the open road - more or less OK again. I'm convinced it gets very rich on the overrun, or descending hills on closed throttle.

So, back in the shop I am thinking that I have the idle mixture screw set way too rich - but it's only two turns out. My second thought is that there is an internal leak - possible in the bi-starter, or possibly the bi-starter is not closing fully.

We'll have to pull the carburetter off again. I found a useful site here, which takes a while to load but has some great pictures of a 26 AHD strip, refurbish and rebuild.

Solex 26 AHD data for the record...

For the record, the jets from my Solex 26AHD are recorded in this post. Here's a diagram to help identify them:

Starter Jet

Pilot Jet

Main Jet

Pilot air bleed

Air Correction Jet

Float Valve

Starter Air Jet

You can download a copy of the Solex Instruction Booklet here.

You can't keep them forever

Much as I like to hoard stuff, there comes a time when you realise that you will never use this piece of timber or all of those used spark plugs you've carried from house to house since you were 16. It pains me to say it, but bikes are no different and much as you love them there are many different machines to sample and precious little time to do it. Am I feeling my age? Maybe, but I also feel a certain desire every time I see a bargain on eBay (there are such things occasionally) or discover some mechanical marvel that I don't have space for. We need to find some direction, or we will be drifting aimlessly until we run out of money or time - or both.

My bikes fill certain needs, if we take a look at what is in the garage at the moment:

• Ariel SQ4 - the summer bike, the fast touring bike, the long distance bike. Perfectly happy with A road cruising at 60 mph, it's big and comfortable. Restored a few years back, it has occasional problems but is the reliable first choice.
• Ariel W/NG - the winter bike, for slower sightseeing trips through the countryside - a bike for bimbling around at 50 mph on Norfolk's B roads. Recently recommissioned, it's still shaking down and spends more time off the road than the SQ4.

Then we have two more bikes that don't get used very much, or at all:

• BSA Bantam - another bike for slower sightseeing trips through the countryside, it was in regular use until the W/NG came along to fill the same role. 
• Ariel FH Huntmaster - in bits, collecting parts. It will have very similar performance to the SQ4 when it is done

So there are really three positions here, to be filled with one bike each since I don't have the space to store any more:

1. The fast, long distance bike
2. The country lane plodder
3. The restoration project

So here's the summary:

• The SQ4 fills the #1 role currently
• The W/NG fills the #2 role currently
• The FH fills the #3 role
• The Bantam is surplus to requirements and will be first against the wall when the revolution comes

In the future, the FH could fill the #1 role and the SQ4 could be sold on; the #3 role could be replaced with a prewar single which would fill the #2 role when ready...

Just a thought...

Solex Emulsion Tube Repair

Regular readers will know that I've had a few problems with misfires lately. I've cleaned the carburetter several times, reviewed and serviced the ignition system and fitted a tufnol spacer and a heat shield to reduce the carburetter temperature. This has worked to an extent, but I still have an occasional misfire. Cold, my 1951 SQ4 runs beautifully – it’s smooth and responsive. Hotter, it seems to stumble when opening up again after slowing for a roundabout or some other obstruction. This stumbling clears itself quite quickly, after which the bike will pull as it should. Occasionally you will get a cough or the feeling of holding back.

Stripping the carb revealed that the emulsion tube was not in great shape, it was slightly bent and has a long hairline crack along maybe half of it’s length. The bend is probably due to it's location and the fact that it is possible to remove the float bowl with the carb in the bike, which leaves the emulsion tube vulnerable - if you are not careful removing the float bowl, you can catch it on the emulsion tube and bend it.

One of my theories is that the area of the float bowl casting forming the well around the emulsion tube is still exposed to engine heat, though I believe I can grip this with an ungloved hand after a run. The tufnol spacer and the heat shield have made a huge difference to carburetter temperature.

The first job was to straighten the tube. I put the straight section in the lathe, and brought a dead centre in the tailstock up to the air jet, to indicate the eccentricity. A bit of judicious bending, guided by the centre, had the emulsion tube straight again.

This is the emulsion tube, after my wiped solder repair. That crack was along most of it's length which would clearly upset the mixture.

Now, David Jones has new emulsion tubes for £20 plus postage, so that would be the way to go. However, if this doesn't cure the misfire, and I think the misfire might be down to ambient temperature, I'll be glad I kept that £20 in my pocket.

We'll test it later this week. Ambient here is now anywhere between 10 and 18 C, so we may not be able to give it a proper test until next summer...

Tyre Pumps

None of my bikes have tyre pumps. I need three tyre pumps. I don't know anything about tyre pumps, and of course I want original pumps that work really well, fit, and look the part. Not much huh?

I don't know who made tyre pumps back in the day, I don't know how to size them, where to buy them, or whether they had tubes or stirrups fitted. Having had a few bicycles I know how they work and could get one working, but beyond that...

So, where did the various motorcycle manufacturers buy them, and who made them? What types of pumps did they use? The ones I have seen are all variations on the bicycle pump theme; no stirrup pumps. Variations are around the materials used; brass pre-war and plastics post-war; and then the air hose connection which takes two forms:

• end of the pump on smaller bikes and the 
• side of the pump, with the folding wire 'stirrup' on larger bikes

What size did they use? Bore sizes:

• 3/4"
• 7/8"

Lengths

• 12"
• 13 1/2"
• 15" - closed length 14 1/4"
• 16 1/2"
• 18"

The pump mounts, and the parts books for my bikes tell me something.

• Bantam: Inflator PN 40-9026; illustration shows what appears to be an Apex inflator with no stirrup
• Ariel SQ4: Inflator PN 6636-29, Tyre Inflator 14in. x 7/8in - the inflator does not appear in the illustrations.
• Ariel FH: Inflator PN 6636-54, Tyre Inflator - again the later parts lists are not illustrated
• Ariel W/NG: The inflator does not appear in the parts list nor in the tool kit list in the owners manual. However the earlier owners manuals picture the bike with a stirrup-type inflator in the usual position on the top chainguard. Chainguard is 14" between the points of the inflator mounts

Pump Manufacturers

Here are a few that I've come up with:

Bluemels

The English company Bluemel was founded in 1860 in East London by Charles William Bluemel, Ernest Adolphus Bluemel and their brother, as yet unnamed. The Bluemel products quickly gained an excellent reputation in cycling and CW Bluemel & Brothers Ltd. expanded rapidly. In 1902, the company purchased an artificial silk factory from Mr. Joseph Cash in Wolston at Coventry, and in 1904 relocated production there from Stepney. The brothers were rather frightened by the size of their new factory, but the wisdom of their choice was shown when additions had to be made to the premises to accommodate their production.

The company’s portfolio quickly expanded to include parts for motorcycles and automobiles. In 1913, the company became incorporated. 1914 Cycle and Motor Accessories Manufacturer. Specialties: celluloid cycle pumps, handles, mudguards, gear gases, dress guards, sparking plugs and accumulators for motors. Employees 550.

In 1938, Mr. Ernest Adolphus Bluemel, the last of the three brothers, passed away. By this time, the company had expanded from an initial 150 employees to over 600: described as a modern factory, its chief products were plastic mouldings in bakelite, steering wheels (to MG for example), and pumps, and to a lesser degree, bicycle mudguards and gear cases. A second generation of Bluemels, Frank William & Roland Edward, continued to expand the company after the death of the original founders.

In 1948, the company began to manufacture car parts for Jaguar and Austin Martin. By 1961, the portfolio included auto, bicycle, and motorcycle accessories, plastic mouldings, dials, and nameplates. In 1983, the company faced insolvency. British Cycling wholesaler, Chicken, recommended to SKS owner Willi Blome to look at Bluemel’s pump and mudguard company in Coventry.

Models:

• 'Motorbike' 

Apex Inflator Co. Ltd.

I'm struggling to find any company history for Apex, but I have these adverts:

Apex advertisement from 1927

Apex advertisement from 1931

Advertising tells us Apex manufactured a range of bicycle pumps

• 'Bailey Super', a 15" pump with a celluloid covered steel liner, 'solid drawn' (seamless) brass plunger tube. The most expensive Apex pump
• 'Superlite', a 15" celluloid pump with a seamless brass plunger - the lightest Apex bicycle pump
• 'Lastwell', a cheaper 15" bicycle pump with a celluloid tube and a split steel plunger

Apex also made brass pumps, with seamless brass or split steel plungers. You will notice that none of these pumps have stirrups, and one conspicuously absent from the advertisements is the 'Thapex', which appears to be the one favoured by the motorcycle manufacturers...

Here are a few more bicycle adverts, which are important to this story. You will see why in a minute.

Apex advertisement from 1945

Apex advertisement from 1946

Apex advertisement from 1949

Apex 'Thapex' pumps were widely used by Brtish motorcycle manufactureers; an Advertisement in a 1931 copy of Pitman's 'Book of the Mathcless' by the ubiqutous WC Haycraft advises that Thapex pumps had been used by Matchless for over 10 years.

Charles Britton

I don't know much about these. Charles Britton was apparently Great Grandfather to TV's Fern Britton; Vincent famously used a 13 x 7/8" Britton pump

Dunlop

Dunlop produced its first tyre for a motor car in 1906. The first rubber estates in Malaysia were acquired, in order to ensure a supply of raw material, in 1910. Construction began on the 400 acre Fort Dunlop headquarters and production site in Birmingham in 1916. Dunlop was the fourteenth largest manufacturing company in Britain by 1918, and its only large-scale tyre manufacturer. It had a market value of £8.9 million in 1919.

Dunlop began to diversify from tyres from 1924. It entered the sports market in earnest when it acquired the tennis racket manufacturer F A Davis. Charles Macintosh, the raincoat manufacturer, was acquired in 1926. The Malaysian estates were expanded over time, and Dunlop was the largest single landowner in the British Empire by 1926.

By 1930, Dunlop was the eighth largest public company in Britain, with a market value of £28.2 million. The company was a major industrial supplier for Britain during the Second World War, producing the bulk of rubber tyres and boots for the war effort.

By 1946, Dunlop had 70,000 employees, and sales outlets in nearly every country in the world. By 1948 Dunlop was the tenth largest British company, with a market value of £55.9 million.

Dunlop’s fortunes were closely interlinked with the British car industry. In 1950 Britain was the world’s second largest car manufacturer, and the world’s largest exporter of cars. Many of these cars were fitted with Dunlop tyres. In the 1950s Dunlop accounted for almost half of all tyre sales by value in Britain.

By 1955 Dunlop employed 100,000 people, and was the second largest private employer in Britain after ICI. In 1959 Dunlop was the twelfth largest company in the world outside the US.

Dunlop began to decline from the early 1960s as it was slow to adapt to the new market for steel-belted radial tyres. Performance was also undermined by the decline of the British car industry.

Pumps from Around the Internet

Internet research, using various keywords and spellings reveals a number of pumps, designs and manufacturers:

Unknown Brass Pump

BSA PN 27-8958, Inflator for WM20

Bluemels 'Motorbike'

Dunlop Inflator

An EBay sale, this inflator was fitted to a 1956 Triumph T110. The design of this pump suggest it was made by Apex.

Similar handle style to a Thapex?

Similar end cap to a Thapex?

Similar engraving to a Thapex?

Pumps and Ariels

Apex Pump on Ray Tolman's 1937 RH

Handle from Ray's pump

Original APEX from David Andersen's 1949 RH

Original APEX from David Andersen's 1949 RH

My Pumps

I've bought two Apex pumps for two of my Ariels, both speculatively, both from eBay. Here we go:

Early Thapex

This is a pre-1949 15" x 7/8" Thapex, that will go on the SQ4 - Its pretending to be old stock, sitting on a shelf at Selly Oak until it was fitted to my SQ4 in 1951.

It's got a black painted stirrup with no evidence of plating

It's got the early style handle, shown in the 1927 advert and also in the 1949 advert as the 'old style'

It's go the early logo on the body sleeve

It's got 'Made in England' moulded into the end of the handle.

It's got a steel end connection and a plated brass gland with a relatively light internal buffer spring.

Later Thapex

This one is post 1949 - there is a later style, but this is not it...

Very similar design, with some detail differences. Celluloid coated steel body again...

Post 1949 handle with 'Made in England' moulded in - very similar to the Dunlop pump, do you think?

New body logo, engraved and filled with gold paint

Alloy end cap, with cadmium plated stirrup

This one has it's washer and fittings. Notice the buffer spring is heavier, and the gland nut is Bakelite; that round head screw is 2BA and fits in a square nut pressed in to the plunger tube.

This one is fitted to my 1958 Ariel Huntmaster.

Pump Repairs

There are a couple of posts on repairing these pumps:

• Making new washers - click here
• Making new connectors - click here