we have lift off – thanks to Bernoulli…

and a few other things as well.

First, there’s the engine de-coke and re-build. Whilst doing this, I opened the exhaust port a little and opened the exhaust port throat a little more, smoothing the flow as best I could. A new crankshaft seal was fitted on the drive side and I took particular care to seal the small gap above the key way slot, in the primary drive sprocket, as some primary compression can be lost here. The little end bush also seemed a little tight, so the bush was gently eased using 1500 grade wet and dry sandpaper.

Second, I’ve flexibly mounted the carburetor. Now I was quite nervous about cutting the inlet manifold as there’s no going back but I did it anyway and fortunately, it worked out quite well.

dsc_0049.jpg

The advantages I hope to gain are:

  1. Reduced vibration of the carb that could be causing the float to bounce and flood with petrol; a persistent problem I’ve had,
  2. Reduced heat transfer to the carb from the engine, that I suspect is causing vapour locking , NB: Petrol boils at 95C, however ethanol boils at 78C, so modern fuel are far more prone to this. Sir Walter has always been a bad starter, 10 and 20 minutes after a hot stop.
  3. Increased clearance between the carb and the wheel as the petrol connector nut can touch the wheel, particularly if the wheel bearings are set a little loose. I cut 6mm out of the manifold and left a 3mm gap between the ends.

The finished job looks quite neat, as shown. You’ll see I changed to a different rubber hose as the black one above was too tight. I just hope the clear reinforced hose I used is ethanol proof, or I’ve a breakdown waiting to happen.  I’ve also added some thick black foam rubber around the inlet spigot, so that it’s supported where it goes through the carburetor cover.

Third, I’ve lapped the float needle to the petrol connector using a new method. Previously I’ve spun the needle in a drill whilst holding the petrol connector between my thumb and finger. The problem with this method is the lapped seat may not be axially aligned as it’s done outside the carburetor body. Consequently, it may leak when assembled.

First step is to make a nylon plug on a lathe, that’s a tight slide fit into the float bowl. Also drill a 1.6mm hole in the centre of the plug (on the lathe) to take the float needle, thereby ensuring the 2 diameters are perfectly concentric.

Then fit the petrol connector into the base of the float chamber with its fibre washer and tighten. Next put a dab of fine abrasive paste (Solvol Autosol) on the needle seat and insert it into connector and up through the nylon plug. Finally carefully tighten the chuck of a battery drill onto the exposed tip of the needle and spin it slowly for a minute or so.

DSC_0064.JPG

Repeat this, cleaning the needle each time, until a good even seat can be seen on the needle. The beauty of this method is that the new seat is perfectly aligned and shouldn’t (I hope) leak.

 

Fourth, open up the silencer to improve gas flow. This also makes it louder and it’s a scientific fact that something loud goes faster; or so it seems. My silencer is the type that doesn’t come apart (for cleaning), so I simply drilled a 10mm hole in the baffle plate that I could see inside the tailpipe. Yes, crude but effective.

 

So what’s this got to do with Bernoulli? Well in 1738 Daniel Bernoulli published a book called “Hydrodynamica” (great title), in which he detailed some principles of fluid dynamics.

In a nut shell, he stated that, “if a fluid (liquid or gas) increases its speed, then the pressure drops” and this is one of the fundamental reasons that a 2 stroke engine works. As the products of combustion accelerate down the exhaust port, they cause a drop in pressure that sucks the fresh fuel charge into the cylinder. So it follows that the faster the gases exhaust, the lower the pressure, the greater the suck, the more fuel is drawn in and the more power you get – simple. And that’s what I’ve done to improve Sir Walter, (amongst other things) and IT WORKS!

He can now climb steeper hills without LPA, he’s revving out much, much better and he even sounds fast.

PS, Bernoulli’s principle is why aeroplane wings generate lift, a spinning football bends, ships can’t pass close at sea, jetties always have water beneath them and why a F1 car’s areopackage works, amongst many other things.  Where would we be without Hydrodynamica?

 

Advertisements

all is not well…

as Sir Walter has lost what little “get up and go” he had. Now he’s more “slow down and stop”. I always had to use LPA (light pedal assistance) on hills but now I’m doing it on the flat!  He also hasn’t revved out correctly for weeks, even when stationary with the clutch in.

_20170908_164608

I’ve tried everything without success, so it’s time for a strip down to see what’s going on.

And the cause became evident very quickly. The Cyclemaster engine is already limited by the exhaust port area, so carbon build-up like this just stops it breathing. If the burnt gases can’t get out then the fresh charge doesn’t get sucked in.

Oddly, the transfer ports were also partially blocked up.

                           EXHAUST PORT                                    TRANSFER PORT

Restrictions like this have a very severe effect on a 2 stroke (negative unfortunately)  as they disrupt scavenging; the effect where the outgoing exhaust gasses suck in the fresh charge. Cyclemaster utilises Schnuerle porting, like the majority of 2 strokes.

Schnuerle porting loop scavenging

The cylinder has a single exhaust port and two transfer ports that are angled backwards. This causes the fresh charge to swirl away from the exhaust port and up towards the spark plug, minimising mixing of the burnt and fresh gases and improving efficiency. You’ll see the exhaust port opens before the transfer ports, when the piston is travelling down, causing the high pressure gases to vent through the exhaust. This flow of hot, expanding gases generates suction behind the flow, that helps draw in the fresh charge – at least when the ports aren’t blocked with carbon. And why have they blocked so quickly in less than 1000 miles?

I’ve added oil to the petrol in the correct ratio of 25:1 (or 4%). The recommended oil in 1952 was SAE30, so I’ve used Coma 2T that’s based on 30 grade mineral oil. It’s Jasco FB rated on ash content, so I expected it to be OK but it’s obviously not. Being positive, the engine hasn’t seized, which is a common problem with the Cyclemaster as they run very hot due to marginal cooling.

So what next?

When re-assembled, I’ll start with semi synthetic (Jasco FD) at 30:1 for a tank or 2, whilst the rings bed in. I’ll then change to fully synthetic at 35:1 and maybe even 40:1 over the cooler months.

And hopefully, Sir Walter will be back to climbing hills again.

I don’t know where this started but I do know where it’s going….

and hopefully, that’s from the East Coast of England to the West Coast, when Sir Walter and I partake in the East to West Adventure.

Or to be exact, from Crimdon Dean (famous North East Holiday resort) to Whitehaven (famous Cumbrian Georgian seaside town), covering a distance of 135 miles and crossing the Pennines with a total climb of 6,666 feet.

However, the build up didn’t go well. Ten days before the event I noticed a broken rear spoke. Oh well, perhaps one broken spoke would be OK? Then Sir Walter started to run weak, wasn’t revving out very well and had less pulling power than the elephant man in a nightclub. And then, when testing different engine setting, I hit a pothole and broke another spoke. So it was engine out, strip down and re-build with just a few days to go. This revealed a broken carburettor casting where it clamps to the inlet spigot (common problem) and I figured it was sliding back off the spigot and leaking air; hence the weak mixture. At this point I must give credit to Pete Stratford and Philip Crowder, who sent me the parts required, at short notice and enabled me to get Sir Walter back together the day before the event – thankyou.

Things were looking good on Day 1 at Crimdon Dean when Sir Walter started first spin, which is quite unusual but it impressed the watching crowd (4 people including my son Christopher). However, It quickly went downhill as the engine was revving even worse and Sir Walter seemed to want to be a plodding 4 stroke rather than a buzzing 2 stroke. Dropping the needle 1 notch helped but anything above half throttle resulted in Sir Walter going even slower. Not good, as a strong 18 mph headwind was forecast for Upper Teesdale. My enthusiasm was further dented when a fellow rider (who shall remain nameless but you know who you are) said I wouldn’t make it to Alston before dark!

 

However, things settled down and Sir Walter was reasonably happy at 5/8 throttle – I know because I’ve added graduated marks to the lever! Soon, I was caught “speeding” through Trimdon but please note, I only pedalled like that for fun and my son certainly found it funny based on the chuckling.

So onwards to Shildon where I tried advancing the timing but it was no better. And then on to Staindrop for lunch, where I tried retarding the timing but still no better. Then on to Egglestone where I tried reducing the points gap but, you guessed, still no better. Time to give up on adjustments and slog up Teesdale. And I did, through some of the best scenery the UK has to offer. Sir Walter was flat out (5/8 throttle) for one and half hours, with “gentle” LPA (light pedal assistance) and it was a delight to spend the time absorbing the wonderful views. This area really is one of the best kept secrets in the UK.

The only downside was the wind. Around Yad Moss, it was getting difficult to make forward progress and I was a little worried I’d get blown off the road and have to spend the night on the moor. However, I knew that support from Martin Wikner was only a phone call away… but I had no signal. And then Alston appeared and it was still light, even at 4:30. Oh yee of little faith, Sir Walter had delivered with a little help from me.

After a quick look around the Hub museum, which is well worth a visit, I then went back down the hill (not the best of planning) to Garrigill to find my B&B and a well earned rest.

The next day started bright and sunny, as Sir Walter posed for an early morning shot.

DSC_0041

Eastview Bed and Breakfast, Garrigill

Now, being the entrant with the smallest engine and slowest vehicle, I decided to get an early start the next day, and head for Hartside an hour earlier than planned. Some would call it cheating but I was getting embarrassing arriving everywhere last. As it turned out I was the third entrant to arrive at Hartside, looking a little like Laurel or is it Hardy. You just can’t get good passer-by photographers these days, or perhaps it’s the subject? Or was I just happy to have made it?

dsc_0043.jpg

It was now onwards and downwards, or so I hoped, to Hesket Newmarket in the Northern Lakes. This leg went well despite some surprisingly steep (up) hills that we just managed to climb under power – no walking for me and Walter.

And then dismay, in front of a large crowd at Hesket Newmarket, he wouldn’t start. So I pedal up the street with the choke on. Then pedal back down with the choke off and still no firing. Pause for thought, twiddle a bit (technical term), try again and heh presto away he goes. But it gets better. After a short distance, Sir Walter really starts to rev well and buzz like he should. Until that is, he splutters and stops. Good news is, I’d switched the petrol off during the twiddling phase. Even better news is, it proves the revving problem is flooding of the carburettor. Only dissapointment is that it’s taken me almost 100 miles to realise this and I only did it by accident; so much for being an “Engineer”. But now is not the time for a carb strip, so it’s onwards and upwards to Bassenthwaite where my wife and son are waiting to meet me at the Lakes Distillery.

The final leg is a leisurely run through lovely english countryside into Whitehaven via Cockermouth, where I arrive last as usual but extremely pleased to have completed the Adventure.

34725513324_d926017176_o

Made it, and aren’t I pleased! So pleased, I even did a burn-out, Cyclemaster style.

Burnout.jpg

And we finished, albeit last to every checkpoint, including the finish. But as Philip Crowder said, anybody can do the East to West on a moped but I was the only one on a cyclemotor.

So the journey is over. Not just the journey to Whitehaven but the journey back to life for a rusty Cyclemotor that hadn’t ran for 50 years. And there is something special about a Cyclemaster; it’s to do with the way you have to work together, particularly when faced with a hill – you help the engine and it helps you.

Man and machine in perfect harmony, now looking for the next challenge.

Acknowledgments

I must thanks, those who helped me from the EACC. In particular Martin Wikner who drove support and Sharon who both planned the route (with help from Dave Watson) and rode it on her little red Honda. And thanks to Neil Catling for his words of encouragement.

And finally, thanks to my sons for their help: Christopher for getting me to the start, Daniel for getting me home from Whitehaven and Michael for looking after Mam and driving her to the Lakes Distillery to laugh at me.

 

It’s all about the chemistry…

but not the emotional type. The chemical type, as used to unblock the exhaust and restore the corroded petrol tank and on my Cyclemaster.

NOTE: THIS BLOG INVOLVES USING SOME VERY AGGRESSIVE CHEMICALS, SO PERSONAL PROTECTION EQUIPMENT SHOULD BE USED, FOR EXAMPLE, RUBBER GLOVES, GOGGLES, FACE MASK ETC.

READ THE INSTRUCTIONS ON THE CHEMICALS AND FOLLOW THEM. ALSO DOWNLOAD THE MATERIAL SAFETY DATA SHEET (MSDS) FOR EACH CHEMICAL AND COMPLY WITH IT – YOU HAVE BEEN WARNED!

First the blocked exhaust.

Apart from cutting the exhaust open, scrapping the carbon out and then welding it back up, there are two, frequently used, methods. The one I’m not prepared to try, involves pointing  an oxy-acetylene welding torch down the exhaust until the carbon is burning, then turning the acetylene off, so the oxygen feeds the burning carbon – a bit like a blast furnace. They say don’t worry about it glowing red and smoke bellowing out? And that it will self extinguish when the carbon has been burnt. But that sounds a risk to far, so it’s the second method for me.

Simply get some caustic soda (sodium hydroxide) from your local hardware store (Wilko in my case) and fill the exhaust with it.

NOTE: Caustic Soda is an aggressive chemical, so rubber gloves (marigolds) and eye protection must be used – as a minimum.

I mixed the caustic soda quite strong, with reasonably warm water (not boiling) and left my exhaust in an old plastic bucket overnight, with bungs in each end. The carbon softens and comes out a black gunge when you rinse it with the hosepipe. I did mine 3 times and the last time there was no gunge, just brown water.

Take extreme care, as the caustic soda reacts with aluminium and can stain chrome – not an issue on the CM. This method was quite simple and worked for me as the exhaust has a nice crisp “pop” now; a sure sign it’s free flowing.

Second, the rusty petrol tank.

My Cyclemaster tank had been stood for so many years, the petrol had crystallised at the top and turned to black rusty gunge at the bottom. I tried various cleaners that all helped a little but bits of rust were still getting into the carb. I hope to do some long distance rides and don’t  want to risk a breakdown due to blocked main jet, so the tank must be cleaned and treated.

This is what it looks like inside and it’s worse further back in the lower section.

dsc_0087-crop.jpg

The method I’m using is to “treat” the inside of the tank with Phosphoric acid. It acts as a rust converter, not remover. The rust is iron oxide and the phosphoric acid converts it to ferric phosphate which is soluble in water so can be washed off – in theory, so let’s see if it works. The acid also etches the steel, leaving a grey surface appearance and increasing the rust resistance.

Remember, use personal protective equipment, as you are working with a strong acid.

My supply of Phosphoric acid came in the form of a ph adjuster used in horticulture, from ebay. It’s 81% concentrated and I bought a 250ml bottle, so that’s 200 ml of acid. The CM petrol tank is small at 2 1/2 pints which is approx 1.5 litres and I used all of the pH Down, so my mix ratio is 7.5:1.

DSC_0088 crop.JPG

The fuel tap and integral filter were removed and the hole bunged with Gaffa tape as I’d read on the internet that this would work. It’s important to add the acid to water, rather than the other way round, then top the tank up to the brim.

I then placed the  Tank in an old plastic bucket and gave it shake every few minutes. It was during shaking that I noticed the garage floor fizzing, like an Alka Seltzer in water, as the Gaffa tape was coming off! SO DON’T USE GAFFA TAPE. Do the safe thing and find a bolt that fits the hole and screw it in securely. Fortunately, I had the hose pipe ready so I gave the floor a good wash down, including washing it Baking Soda to neutralize the acid.

After 20 to 30 minutes I removed the acid, gave it a rinse with the hose pipe for another 15 mins, then rinsed it with a baking soda solution. And this is the result:

dsc_0095-crop-2.jpg

The next step is to thoroughly dry the tank and I used a heat gun to do this. When your are 100% sure it’s dry, give it a spray inside with WD40 or simlar.

Side by side, you can see the improvement is massive – job done, or not quite…

I say not quite, as unfortunately the acid has affected the outside of the tank.

DSC_0098.JPG

It just goes to prove, you shouldn’t believe everything you read on the internet, as I’d read that Phosphoric acid has no affect on paint – wrong! Perhaps I made the acid too strong? Or perhaps the original Polychromatic paint isn’t resistant to acid?

Anyway, I was unsure whether to paint the tank but that’s now been resolved for me.

So the next blog will be my experience on painting the tank and the other parts. Oh and adding those difficult red lines…

eat your heart out Mr Bluemels…

that’s Mr Bluemels of the world famous Bluemels Brothers Ltd. – manufacturer of automotive accessories and more importantly, number plates!

For most of the 20th century there was one motor accessory manufacturer whose name stood for top quality British Engineering and that company was Bluemel Bros Ltd.. Founded in 1860, at one time they manufactured a huge range of superb quality products including OEM steering wheels, auto lamps, cycle lamps and accessories for grand touring cars. They were one of the few regular suppliers to the bespoke coach builders of the 20’s & 30’s, catering to the likes of Rolls Royce & Bentley. As the coach built motor business shrank with the introduction of serious mass production in the 50’s, so Bluemel’s business evolved and by 1961, their portfolio included auto, bicycle, and motorcycle accessories, plastic moldings, dials, and number plates.

BLUEMELS-NUMBER-PLATES-original-1957

However, by 1983 the company faced insolvency. And like so many great British companies they folded. Worse still the name lives on in the guise of SKS Bluemel – a German bicycle mudguard manufacturer – how sad. And so typical of many other great British companies.

So, it’s down to me to make the rear number plate for my Cyclemaster. I doubt I can do it as well as the Bluemels Brothers but I’ll give it a try. The first thing I need is some material and I’ve “acquired” some 18 SWG mild steel sheet and some aluminium sheet. Applying the Colin Chapman principle, the ali would be better as it’s lighter and more suited to my puny engine and equally puny legs!. However, I’d prefer to weld the mounting brackets in place, rather than have unsightly bolt heads showing, so the steel it is; and I’ll just have to work on the legs.

So after cutting the required size, I scribe a line 5mm from the edge to form a “safety edge” (bent back, in other words). The line is positioned in the vice and the blank bent back using a rubber mallet to avoid denting the plate.

Each side is bent back to within 25mm of the corners. I then cut  a suitable radius on each corner with tin snips and formed each corner back, using an old socket.

I left a tab in the centre of the top edge for a rear light. Now, to keep the boys in blue happy, it should really have a clear area on the lens to illuminate the number plate and comply with the Road Traffic Acts. However, I’m a risk taker (and a cheapskate), so I’m just using the Raleigh rear light. My plead for leniency would go like this, “Being practical officer this autocycle doesn’t go any faster than a bicycle. So if you want to record my registration number, in the dark, just walk alongside (or jog if I’m going downhill) and ask me”.

Now I need mounting brackets; one at the bottom with a single bolt fixing i think and one slightly above the middle with two bolt fixing. Bottom bracket first. I cut a strip of steel then formed it into a U shape as shown below, using a suitable screwdriver as a former.

I then turned it over in the vice to close it up, then squeezed it back on itself.

After drilling and filing to smooth the edges and clean it up, the finished bracket looks like this. Ready for welding, once I’ve made the top bracket.

dsc_0048.jpg

Which is a bit more difficult, as I’d like it to follow the form of the mudguard. I started by bending a strip of steel around suitable formers by hand – my bike stand and a screwdriver in this case – see below.

However, my rear mudguard has a raised centre section so the bracket needs a relief groove to clear it. I formed this, using the vice (again) and a screwdriver (again) and a hammer .

and it turned out fairly well. Not perfect but the shape can be carefully improved by using (you’ve guessed) a hammer.

I just need to cut and bend back the tabs and it’s ready for welding onto the plate. To get the angle and length of the right, I used the well tried method of cutting a piece of cardboard as a template – easy to cut to get it right then use it to mark the metal.

Now welding is a bit like brick laying. You don’t need a degree in engineering, you just need years of practice and more practice. I wasn’t a bad oxy acetylene welder in my day but that was in the 70’s. And when I say “my day”, I mean ONE day! So, first thing is to set up the MIG in the “welding bay”.

DSC_0059

I’d love to say the weld below was my first attempt but it wasn’t. “Pigeon droppings” is an apt description of the test welds but it did come together eventually – unfortunately on the last one.

DSC_0061

And after priming and painting, this is the result.

DSC_0081

The last job is to fix the self adhesive alphanumerics and this can be difficult as you only get one chance. The method I used was to apply masking tape as a base line to get them level. I marked the tape with the position of each alphanumeric, leaving me with the task of making sure they were straight.

And now the final steps of drilling, fitting and standing back and admiring.

but the Bluemels Brothers would have nothing to worry about, had they survived.

and finally, some Bluemels adverts from Graces guide,

Im1951MShow-Blumels

Im19360610Cy-BB

Im19250306MCT-Blue

Im1920Cov-Bluemels1

and the last one is a gem.

blu_let-1

I particularly like the bit, “a junior member of staff (male or female) can handle the simple assembly procedure.” In other words, so simple a female can do it – sexism hadn’t yet been invented, just practiced!

And look at the name of the Sales Executive…..

 

More thoughts on the warm starting problem…and some science

After furiously pedalling my warm Cyclemaster to get it to start, I found it began to fire as I rolled the throttle to almost closed. So I’m trying to figure out why, as this could lead me to the solution.

Fuelling control on a 2 stroke normally works like this:

  • Pilot jet – controls idle to around 1/4 throttle
  • Slide cutaway – controls 1/8 to around 1/2 throttle
  • Needle and jet – control from 1/4 to 3/4 throttle
  • Main jet – controls from 1/2 to full throttle

Now the Amal 308 carb is a basic item as it doesn’t have a pilot jet and adjusting screw.  And without a pilot jet, fuelling for warm starting can only be controlled by the cutaway and needle jet. So the next step is to understand how the carburettor works and the answer is the “Venturi Effect”.

The Venturi Effect was discovered by an Italian physicist called Giovanni Battista Venturi and it goes like this:

The Venturi effect is the phenomenon that occurs when a fluid that is flowing through a pipe is forced through a narrow section, resulting in a pressure decrease and a velocity increase.

In a carburetor, the pressure decrease creates suction that causes fuel to be sucked into the passing air where it mixes and gets drawn into the engine. When starting a warm engine with a normal carburettor, the fuel would be drawn through the pilot jet and the pilot jet suction port is positioned just behind the front edge of the throttle slide (engine side). This is the narrowest part, so the point where the air is moving the fastest and the point of maximum suction – see diagram below.

slide-closed

However, the Amal 308 doesn’t have a pilot jet, so fuel can only get drawn from the Needle Jet and here, I think, lies the problem; it’s in the wrong position when trying to start a warm engine! The suction just isn’t enough to raise fuel up the Needle Jet Tube, at low air flow.

Also it gets worse if you open the throttle. This increases the area above the needle jet, so the air velocity decreases and the suction decreases to the point where no fuel is drawn into the air – hence it won’t start. If some fuel is drawn up, the engine doesn’t fire as it’s getting too much air and the mixture is too weak to fire, as the throttle slide is up.

slide-open

However, as you close the throttle, the air flow is restricted, the mixture gets richer and the engine fires.

I believe this may explain the poor warm starting many Cyclemasters suffer.

It also explains why tilting the carburettor to the left helps; it simply lets a little petrol run into the venturi. And you probably noticed in my “kick-start” video that the engine started on idle, i.e. throttle slide almost down to get down to get maximum suction at the needle jet and limited air.

So, to start your warm engine, I suggest:

  1. mark the idle position on the throttle control and set it just above this point,
  2. tilt the bike and engine to left for a few seconds (experiment with angle of tilt and time),
  3. kick-start or pedal the bike.

and hopefully, it’ll start – before you run out of breath!

Good luck, I hope this helps and please let me know your experience.

Addendum

For those of a scientific mind the Venturi Effect is governed by the Bernoulli principle. And Bernoulli’s principle is why aeroplanes and birds can fly, why a football follows a curved path when kicked with spin and why ships must maintain a minimum distance when they pass in opposite directions. I can explain if anyone wants to know?

a pearl of wisdom for starting a warm cyclemaster – or it may be baloney..

you decide.

This probably isn’t new to experienced Cyclemaster riders but I’m not one of them, so to me it’s a discovery. A discovery, from the need to stop pedalling up and down the road, to start my Cyclemaster “Sir Walter” and annoying the neighbours.

The first 15 mile ride has noticeably improved the engine, it even sounds crisper and it was definitely going better at the end. However, it does have a problem starting after standing for 10 to 15 minutes. Starting from cold – no problem. Starting straight after stopping – no problem. But after 10 minutes it just takes a lot of pedalling before it fires. My Cyclemaster friend, John, tells me he also has the same problem and I know from the internet that others do, so what’s the cause?

Well, I’m thinking the motor runs a fairly weak mixture as it gets 240 MPG and this makes it reluctant to start when it’s cooled a little. I’ve tried the choke but this just floods it as I can smell petrol when pedalling and it doesn’t have a float “tickler” to raise the fuel level and richen the mixture.

However, it seems to start really well “kick-started” as shown below

and I have an explanation and it goes like this.

When you kick-start the way I did, the bike and motor are tilted to the left. Now the float bowl is on the right of the carburetor and the petrol exists the float bowl on the left. So when you tilt left you raise the fuel level at the main jet and this richens the mixture – like “tickling” the carb.

fuel-level

This theory may be a load of gibberish or baloney (or rotvälska for my swedish followers) . Or it may be a pearl of wisdom. So I’d be interested in your views and whether it works for other Cyclemaster riders?

You could of course, pedal in a fast, tight circle to the left and this may work as well but I take no responsibility if you get dizzy and fall off!

almost a hen with teeth – unbelieveable but true

The amazing power of the internet (or the “herdy gerdy” as my mother calls it) has come good. That and my pig headed determination, has found the closest thing to hens teeth I’m likely ever to find – in Poland of all places.

I’ve found a manufacturer of hub parts that are pictorially very, very similar to the 1950’s Cyclemaster Eadie Coaster hub. My guess is they are based on the same design as the Cyclemaster hub that was originally made by BSA in Birmingham; a Polish manufacturer has just bought or “used” the design. But they only sell to Distributors and the nearest is in Slovakia!

However, I’m on a roll, as Miroslav of the Slovakian distributor is willing to send the parts I need. The only issue is whether I can be sure they will fit my Cyclemaster, based on photos only but it’s worth the risk as I can’t get the parts anywhere else.

It’s not identical, so I’ll need to make an extension piece but heh I’m an engineer – I can do anything (within reason and given time…and I’ve got plenty of that)

So it’s bank transfer and fingers crossed!

.crossed_fingers_208680