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Chat 18


The answer to Chat 17 four picture quiz.  The link is TEA.  Correct answers from:- Pat Robotham (He once lived briefly on a tea plantation so knew what the plants look like), Kath and Walter Partington, Don Eades, Kath and Don Sales, Malcolm Bridges..

 1. Tea Caddy.  2. Tea Clipper.  3. Boston Tea Party.  Tea plant tip. 


The piston quiz will run for a few Chat editions with an extra clue each time.  What is this piston from? 
The first clue was:-  It is not from a bike engine, it is from a car.  The new clue is:-  Blue oval/water crossing the road put some money into early development but that is not the answer. Eddy

chat_images/piston.jpg  Answers by email to: edgrew@virginmedia.com

 

 

 

 

 

 


Here is the new picture quiz for Chat 18.  What is the link to these two pictures?  Answers by email to: edgrew@virginmedia.com

chat18_quiz_pic1.jpg chat18_quiz_pic2.jpg


Part One of John Grew's first bike and what came next:-

“I’m Pickin’ Up Good Vibrations”

The ‘Beach Boys’ released their single Good Vibrations in October 1966. I believe motorcycling is a visceral experience, well it is for me, and my ‘guts’ were indeed pickin’ up good vibrations. The motorcycling bug had well and truly bitten.

Three of my mates and I pooled our paper round money and purchased two old 125 BSA Bantams in the early sixties. Although we were young teens, we had just enough mechanical knowledge to get them running and enough pluck to ask a farmer on the outskirts of Ashby if we could use his “spare” muddy field as our race track. To our surprise he agreed, and we laid out a course with jumps and bumps.  A mix of bald tyres and slimy mud sure did teach us how to ride a motorbike, albeit a 125 Bantam!

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John tackles one of the “jumps and bumps” on the Bantam.

Teenagers are often labelled as rebellious and sometimes destructive, but we felt that we weren’t doing anybody any harm apart from the sound pollution from the degutted silencers. Youngsters always equate more sound to more speed and we were no exception. Some of our “racing” often stretched into late evening and this was nearly our undoing because our field backed onto a council housing estate.

vibrations_pics/Bike a2.JPG 
Mates Phil and Steve race around the field - note the council houses in the background.

One evening we spotted a darkly clothed figure approaching us across the field. It was the local policeman. “Now then lads, we have had complaints from the tenants that you are making a noise in the evenings”. We responded that we weren’t doing anything wrong apart from the noise, and at least we weren’t smashing up telephone boxes like some of our bored peers. “Good point, so carry on regardless, but don’t race around after 8 pm”. We couldn’t believe our luck!

The wonderful watershed age of 16 was now approaching and my thoughts turned to acquiring my first real road bike. My paper round money was redirected from buying petrol and two stroke oil for the Bantams, and I accumulated circa £20 that would eventually purchase a second hand Triumph Tiger Cub from Pook’s of Thurmaston.

I de-coked the Cub with the help of my dear brother Eddy and the bike was waiting to be ridden for the first time at the end of the school day on my 16th birthday. I could only just afford to buy a crash helmet, so there was no money for luxuries like a camera; hence no photograph.

I applied for my test the next day and the date was in about six weeks. The test was duly passed first time in Burton on Trent. I was lusting after a “big” bike, but paper round money wasn’t going to buy much at all and certainly nothing exotic. I’d heard on the grapevine of a 350 Matchless for sale that was very cheap, so leapt at the chance and a few quid had the 1957 G3LS in my hands. This typically unloved and neglected Matchless had no mudguards and required some TLC to get her running anything like, but I had my first “big” bike.

vibrations_pics/M6.JP  vibrations_pics/M9.JPG
First ride on the G3LS with alloy guards and typical ‘bulb’ horn and on the 350 in one of Mallory’s bike park fields – late 60’s

Just a reminder that the Swinging 60’s not only offered “free love”, but also ushered in the dominance of the Japanese motorcycle industry. There were hundreds, if not thousands, of unloved and neglected British motorbikes about, just like my Matchy.

This was proven time and time again whenever I parked up my G3 in a populated spot. “Ay up lad, I’ve got one a them in me shed, you can have it for five quid. In fact, if you pick it up straight away you can have it for nowt”. This occurred frequently. I took up all similar offers and ended up with a rented double garage full of A.J.S and Matchless motorbikes of all descriptions. If only I still had them all!

My cache of all things AMC provided the G3 with some original mudguards and a few other bits that turned it into respectable order. The cache also gradually gave me the experience of riding virtually every post war AMC model that came out of Plumstead. There were twins and singles of all capacities that were gradually made road worthy, although none of them were ever in concours condition; a trait I still have! A few other local Matchless owners and I got together and started a section of the AJS and Matchless Owners Club that is still thriving today.

I had signed up for an engineering apprenticeship and now my income was a bit higher than paper round money. This facilitated the purchase of a 1963 650 twin that was in nice roadworthy condition from a shop in Brum. I thought that I had gleaned enough AMC knowledge to tackle any shortcomings in these Plumstead bikes and coughed up the hard earned cash. It was in very good original condition with good brakes for its day, 12 volt electrics and no oil leaks. The only down side was the inherent vibration when travelling at speed. The 70 MPH speed limit had been introduced mid 60’s, but the lack of speed cameras years ago facilitated “windows of opportunity” that one couldn’t resist. The G12 would cruise at 80 plus with ease, but the vibration was terrible, especially through the handlebars. If you took your left hand off the bar the clutch lever was a blur at 85.

Around this time brother Eddy had a bit of “disposable income” and bought a new Norton Commando 750. He let me have a go on his new bike and this is when I had the epiphany. That first ride on the Commando was unbelievable. Seventy MPH and NO vibration, then 80, then 90. Is this magic? Although the Matchy twin was good overall, the lack of vibes on the Norton was a revelation. I had to have one! I sold some AMC bits and part exchanged the twin for a new 1972 Commando Interstate; my first new bike. Now I was “pickin’ up no vibrations”, and very nice too!

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Typical Norton Commando 750 Interstate

I liked my Commando with its low down torque and mine handled well, despite some people having misgivings about the ‘isolastic’ frame design. Eddy and I kept a close eye on our isolastic bushes and adjusted them accordingly at regular intervals. However, my love affair with the Norton was gradually tarnished by poor build quality. The Commando frame concept was an instant fix for the vibes and the bikes sold well. I seem to remember that the Commando won MCN’s bike of the year 5 years running. Unfortunately, the factory couldn’t keep up with demand and probably wanted to cut production costs, so they farmed out some of the work. The quality control went downhill and my bike was a victim of this policy. The paint came off. Bits fell off. Toyota had to learn this same lesson a few years ago when they became the world’s largest car producer. They couldn’t make all the parts in-house and the problems started.

I bought the bike from a dealer down south who didn’t want to know about my dissatisfaction. Norton still had their engine factory in Marston Road, Wolverhampton and I rode over there to complain about the bike. Someone in authority did speak to me. I asked why their test riders didn’t discover all these faults. He replied, “We let owners undertake our road testing and development”. That was the final straw.

Thoroughly disillusioned, I returned home and read my Motor Cycle Sport monthly magazine over a cup of tea. Eddy and I enjoyed “Sport” every month and we still have all the copies from the mid sixties up until they went “glossy” a few years ago. The content used to be written by intelligent, experienced motorcyclists and engineers and was always a good read. One article was about Phil Irving, a well respected engineer and I’m sure many of you will know of his involvement with Vincent, Brabham Racing etc. Like Norton-Villiers years later, Irving could see the benefits of  retaining a compact, lightweight vertical twin engine. He was a clever man and worked out that it would be possible to reduce the inherent twin vibration by approximately 50% simply by changing the “piston together” 360 degree crankshaft to an “out of step” crank that would mimic a V-twin. There would be minimal tooling costs in the production. The story goes that he went round the British factories at the height of twin production with this idea, but nobody would listen.

I was just about to make another cup of tea when I turned the page of the magazine and there was my “second love”. A full page colour picture of the new 750 Ducati ‘round case’ V-twin. It was in Ferrari-esque red and looked fabulous! I couldn’t really afford one, but you know the power of love.

Some more AMC stock was sold to feed my desire and the Commando was part chopped for one of the first 750 GT Ducatis in the country. Unfortunately, the only colour was in a sort of insipid yellow/gold, but this was balanced by a glorious engine that was smooth, and sounded fantastic.

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Typical Ducati GT 750 in insipid gold

In my humble opinion the Italians produce beautiful women, cars and motorbikes etc, but they tend to be temperamental and sometimes unreliable. My Ducati was no exception and there was a serious problem on its first trip out. Was I doomed?

I bought the bike from Coburn and Hughes who were the importers. There was a very bad oil leak from the front cylinder head joint. A quick check on the head fasteners found them tight. It all looked pretty serious to me, although it could just be the head gasket. My enquiry to the importers was not fruitful. “Your bike is one of the first in the country and we haven’t got any spares, not even any gaskets”. Frustration set in.

The oil leak was bad enough, but the fluid wasn’t gushing out. I hatched a plan. I telephoned ‘incognito’ to inquire about purchasing a 750 Ducati at the same shop and yes, they had one in stock. I travelled down south early next morning and kept an eye on the oil level. I knew that the workshop entrance was round the back, so I rode the bike behind the shop. I didn’t speak to anyone as I opened the large workshop door and pushed the bike inside, on to the centre stand and then just sat there. Mechanics and staff kept passing by and gave me inquisitive looks. Eventually someone asked if they could help. “I’d like to talk to the manager, and by the way I’m NOT moving until I get my NEW bike fixed”. The manager arrived and repeated that they had no spares. I explained that my spares were on the new unsold twin in his front window and if his mechanics were too busy I would do the work myself. This I duly did. The end of the day saw me riding my Ducati, with no oil leaks, up the M1 back home. The problem was a cracked cylinder liner and the new donor bike’s bits did the trick.

Does lightning strike twice, or was it déjà vu? Like the Commando, the bike handled well and was smooth, but the paint came off and bits came off just the same. Typically, the electrics were unreliable. I was disillusioned again and the bike had to go.

A short flirt with a new Norton-Villiers built 750 Triumph Trident was déjà vu yet again. Smooth engine, great handling, but it went wrong straight away and the technicians at Small Heath never did fix the clutch problems. The bike had to go!

It’s funny looking back after owning several Japanese bikes in recent years. In the early seventies there was still this stigma attached to owning one. “Jap crap” was a phrase still to be heard, and although I wasn’t so radical I was still trying to be patriotic apart from my “fling” with the Ducati. That said, there was no way I would consider owning a BMW. They were too expensive, foreign and meant for old men with pipes and slippers!

So eating my words saw me test riding a new 750 BMW. I was earning more money now so a BM was within my financial reach. The salesman said I could have the bike all morning, but I was back within an hour. He had a perplexed look on his face as I returned much earlier than expected. “Is there a problem with the bike?” I replied, “No, but that is the worst bike I have ever ridden”. The boxer engine was indeed smooth, but the engine speed clutch gearbox and shaft drive “jacking” were completely alien to me. The salesman explained that BMW’s were like Marmite, you either love them or hate them. “Come back and have full day on it to get the true flavour”. This I duly did and so began a history of having a boxer BMW in my possession ever since. They certainly are like Marmite and actually, I really do love real Marmite!

vibrations_pics/Bike c5.JPG 
Touring France on the 75/6 BMW circa 1980

A familiar story now unfolded as family and mortgage soaked up the finances and it would be many years before I could entertain a new bike purchase again. So what was I left with?  I was lucky in keeping hold of my BMW and one Matchless single after selling everything else mechanical to raise the cash for a house deposit. I was also left with the experience of “Pickin’ up good vibrations” or not, and the methodology of engineers in trying different ideas in order to reduce this irritation.

 To be continued……


Racing Remembered

John Stone raced on the Isle of Man in the 70' and 80's.  Here he shares an Isle of Man Reminiscence.

John Stone at Signpost 1984 TT practice.jpg

In the late 70's TT I had entries for the Junior, Senior and Formula 111 races.
The plan was to run a borrowed LC motor in one TZ race bike then swap engines after the Formula 111 race.
I managed to destroy the LC motor very quickly in practice (another story) so back in went my trusty TZ engine. Only problem was that it wouldn't run other than an odd pop and bang.
OK. So I changed the ignition - no improvement. Changed the carbs - no improvement. Even had the crank rebuilt with new seals - no improvement. In desperation I took it up the paddock for a run on the diagnostic dyno. No fault could be found (other than it wouldn't run !) Everyone perplexed.
We were sitting in the garage the night before the race despondent. The guy who owned the garage came up to commiserate. He said that although he knew nothing about engines let's go through it systematically.
OK he said. Exhausts first. I said nothing can go wrong with expansion chambers that is not visible. Nevertheless he said blow down them. Well I tried but could not because they were blocked.
I then remembered that I had put some rag plugs in the exhaust stubs as protection. (Against what ? spiders? mice? …)  When the engine first fired up the rags had blown down to the tail pipes and blocked them. Of course noisy friends were there to cheer and take photos of me with a big black ring round my mouth after trying to blow down the pipes.
They were very understanding and hardly laughed at all. But the day was saved.
Not quite the end of the story.  It was a push start in those days. Engine fired, running well.  Jumped on heading for St. Ninians Crossroads.
The left footrest then folded down. An enthusiastic helper, doing his best in last nights panic had fitted it upside down. Luckily I was running ' British' left side rear brake in those days. However it was a long hard four laps trying to jam my leg into the fairing for support.

One to remember!  John Stone


In Chat 17 Racing Remembered I mentioned I had a noise testing story that I would tell another time.  Here it is.  Eddy

I was doing the noise testing at a Vintage race meeting at Oulton Park.  I called out the numbers that had been selected for noise testing on that day.  As usual we randomly picked three or four riders out to be tested.  On this day one of the people to be tested was Roger Moss and his Scott.  I waited for quite a while and Roger hadn't turned up, so I went out into the paddock, found Roger and told him he had to be noise tested.  Roger started the Scoot and I checked the reading with the meter.  It was way, way, over the limit the limit.  The limit these days, I think is 105db, back then I think it was higher maybe 115db.  I think the Scott tested at something like 120db, well over the limit.

In those days most racing Scotts used two very short open megaphones that terminated just underneath the engine.  Now Roger, gentleman that he is, said okay I'll put it back on the trailer.  He accepted  he had been caught and wasn’t going to be racing the Scott at that meeting because it was too noisy. 

There's a little bit more to this story because Roger and his Scott had been noise tested several times in the past and it had passed the test.  How come it got through the noise test before and today, with the bike in the same specification it had been before, it hadn't passed the noise test?

If you know a little about how most two strokes work the “valves” are holes or ports cut into the barrel.  They open and close as the piston by being covered or uncovered as the piston goes up and down in the bore.  These ports open are open or closed irrespective of whether the engine is running forward or backwards. 

When I had my MZ Super 5, occasionally when starting it would do a little backfire and start running in reverse.  If you hadn’t noticed, it was quite a shock to engage first and find yourself going backwards as you let the clutch out!

Here's how in the past, Roger had got the Scott through the noise test.  He had always pushed the Scott down to the testing area with the engine already running.  The trick was that he had started it by pushing it in reverse.  The engine running in reverse made less noise.  On this occasion he couldn’t start it in reverse as I was watching which would have given the game away.

There is another little thread to this story.  Roger went away and built a new exhaust system with a custom built expansion chamber as used by more modern two-stroke racers so when the Scott returned to racing it was quieter and even faster.  Eddy


WARNING.  If you get a link called "Ronan Keating sings Christmas carols" don't open it, it's a link to Ronan Keating singing Christmas carols.����


Here something for the machinist amongst us:-

Tony Harris shows us how he repairs Norton twin exhaust threads.
 
We all know about the Commando dodgy exhaust threads and how difficult it is to keep these tight and not let the exhaust pipe fall out, along with the thread.
I will explain in pictures because like me, half of you can't read. A pictures says a thousand words, and all that.

Whatever we do its got to be stronger than the origin thread in the cast alloy. There are a few ways to do this, some more expensive and time consuming than others.

First, I turn the inserts up in Dural with the correct thread internally screw cut.

Exhaust thread repair/Nov 2016 1.JPG

Then I set the head up on an angle plate on my milling machine.  I then bore the what's left of the old thread out and make the hole about .001" smaller than the outside diameter of the insert.

/Exhaust thread repair/nov 2016 4.JPG

I then push the insert in flush with the head.

Exhaust thread repair/nov 2016 6.J

Next, drill down in two places, half in the insert and half in the head and screw in two grub screws.

Exhaust thread repair/nov 2016 9.JPG
The new exhaust threads installed.

Exhaust thread repair/nov 2016 10.JPG

I have never had one come lose or strip, lucky eh. Tony


Another unusual model engine form John Goodall's collection.  Eddy

This is the Cetonia radial engine made in Paris, France in 1911.

Cetonia radial engine/DSCF0001 (10).JPG

It is powered by compressed Co2 gas and works with a slide valve on each cylinder just like a model steam engine. It originally had a hot water jacket surrounding the inlet pipe to the engine which, like the Co2 tank is missing.  This caused a boost to the gas expansion allowing it to produce 1.03 BHP no less at 1700 rpm, driving a 33 inch diameter propeller.

Cetonia radial engine/DSCF0002 (9)

The engine is very compact for such an output power measures but 7 ¼ inches diameter and weighs 1.72 lbs.  ("Sorry, being conscientious, some might say contentious objector I don’t do metric!!)  Even so it would have struggled to fly a model aircraft in its day because of rudimentary construction and poor understanding of model aerodynamics

Cetonia radial engine/DSCF0003 (9).JPG

The only other model engines earlier than this one that I know of, are depicted in Sammy Millers Museum where a Stanger Motorcycle is exhibited. Stanger was a garage owner and a pioneer of model engine design and construction in this country.  He built many model engines and set British records before 1910.  One of his most successful engines was a 15cc three cylinder inline two stroke and he also made a "V" four, four stroke engine.  John Goodall.


Thought for the day:-

You don't need a parachute to go sky diving. .............  You just need a parachute to go sky diving twice.


A comment from Mick Leach that I liked:- I think I have learnt more about other club members in a couple of weeks (of chats) than in a month of club nights.

And a little more profound:- Learning of other members adventures and exploits prompts me to reflect on what good lives we have had.  We are fed up looking at our toys, wondering when we can go out to play.  We have never experienced the fear that our fathers and grandfathers had, waiting for the signal to go into action with a bayonet fixed or seated in an aeroplane and being shot at.

Next Chat issue:-  May 10th would have seen us enjoying the 2020 Burton Parade.  With the help of one or two other contributors I hope to bring you a Virtual Burton Parade.

Also in the pipe line for future Chats I have, Motorcycle Memories from Pat Robotham, another interesting model engine from John Goodall and the Part One of the articles from Tony Harris about his home made Ariel "V" twin that he had published in Cheval, the Ariel Owners magazine.