Kemenyek: January 2012

Sunday, January 22, 2012

Alpha Bearings, UK....a look into some older master catalogues in particular for Velocette information...

Alpha Bearings Limited are a company well known in English motorcycling circles for big end assemblies....
Actually they have made other items over the years including engine valves, small end bushes, valve guides and after acquiring the Romac Cable making business, supplied speedo and tacho cables as well amongst other things.
Situated in Kingsley Road, Netherton near Dudley in the West Midlands of the UK, I remember when I first visited them on a business trip in September 1986. I'd borrowed a BMW R100/7 from a long time UK friend, Elvin Bitchell to run around the UK and Europe ( a cheapskates business trip...actually I relished the riding and camping it entailed...but that is a story for perhaps another post..) visiting various businesses of interest, predominately speedometer oriented, and so Alpha were on the list.
It was one of the "hole in the wall" type entrances and some shock when I came upon it riding slowly down Kingsley Road...

Entering the open door I advanced down a darkened passage to one of those half doors such as you find in a horse stable, the top half open..."hello in there!" ...a friendly face appeared and we introduced each other....
Enough of the preamble, I've several Alpha master catalogues I want to share data from with you, this will be Velocette oriented, but for others, the introduction side of the catalogues make interesting reading.
Perhaps I'll publish a more complete listing for other motorcycle brands at a later date...
I've one catalogue up to 1953 and the other up to 1966.
Lets look at the 1953 one first...
I acknowledge copyright to Alpha Bearings Ltd., who are still actively in business...
Left click on the images to enlarge them all for better viewing....

The 1953 catalogue cover...the books came from a now defunct Sydney Motorcycle Accessory firm, Omodies Ltd., and as you can see by the stamp on the top of the cover the Australian importer for Alpha at that time was Eustace G.Jones in Melbourne, Victoria.

Flyleaf for the 1953 catalogue....
Following are information pages from the 1953 catalogue, omitted in the 1966 edition...

The 1966 Alpha Bearing catalogue cover...

The introduction of the Alpha Tru crankshaft truing jig for 1966...

Alpha small end bush listing to 1966, covering Velocette.

Alpha small end bush codes for Velocette to 1966.

Alpha big end codes and dimensions covering Velocette to 1966.

Interesting information....
The codes....
V1..... 1932-1940 GTP
V2.....1934-1948 MOV
V3.....1934-1960 MAC and 1936-1948 KSS MK.2
V4.....1935-1948 495cc, 81 x 96 MSS
V5.....1938 Mk.7 and 1939-1950 Mk.8 KTT
V6/9..1956-1971 VENOM, VIPER and 1954-1971 86 x 86 MSS
V7......1957-1964 VALIANT
V8......1962-1965 VICEROY
Ever wondered what the big end bearing clearance was for an Alpha Velocette big-end, say the V6/9 for the 500cc Venom/MSS/ 350cc Viper?
Taken from the above chart.....
The internal diameter of the bearing ring for the con rod is 1.8765"
The diameter of the crankpin track is 1.500"
The diameter of two 3/16" rollers are 0.1875" x 2 = 0.375"
So.. 1.8765 less 0.375" less 1.500" = 0.0015"
A thou and a half....
When oiled guess you'd have difficulty in feeling any play in the newly assembled bearing.....

Labels: Alpha bearings-Velocette

Sunday, January 15, 2012

M.I.R.A....1956, a look back into the early times of this motor vehicle research establishment in the UK....

If you're a reader of earlier English Motorcycle magazines and road test reports, you'd have come across the initials, M.I.R.A.
Motor Industry Research Association...a facility based at Lindley near Nuneaton in the UK....
Now as readers of my blog will be aware I've lots of literature accumulated over the years and having been involved in automotive and motorcycle instrumentation, I have a good selection to cover this aspect of my life.
I was looking back through some "Smiths Automobile Review", an in house magazine from the Smiths Instrument group and an article in #11 of 1956 forms the basis for this posting.( acknowledgement to Smiths Industries for these)....

The article in question was on M.I.R.A , now I don't intend this post to be a formal treatise on the body in question, just a general look to bring you perhaps a little more knowledgeable on it....so lets read through the items and I've a few additional comments.
Before this I was in touch with motorcycle historian Peter Jones from Canberra and he offered some initial comment.

"....Formed in 1946, I believe with financial support from the British Govt. About 1/2 of the finances were raised from within the Motor Industry. This was seen as a necessity in the Motor Industry to allow for proper high speed testing of British cars to give them an edge over those being produced overseas - especially Germany where BMW had access to the remaining wartime German jet aircraft high speed testing and wind tunnel facilities.

Around forty or so sites were initially looked at, inc both Donnington and Silverstone, before settling on a ex wartime RAF airfield at Lindley. This was named after a nearby farm called Lindley Hall Farm - sometimes known as 'The Geographical Centre' of UK. The site covers 760 acres. There are some 58 miles of track, covering various options for both high speed and crash testing.

The facilities first became available to motor car manufacturers in Oct 1948, when Jaguar (I believe?) took a prototype sportscar there for secret testing. This car later (several years) evolved into the E Type. I understand Triumph were the first motor cycle users, testing a twin cylinder 500 there in 1949. Initially it was quite relaxed, where both cars and bikes might both be on the track at the same time - as it was quite expensive to book the facilities for sole use. Later, as safety became more and more an issue, this relaxed approach disappeared. It seems that both Velo and Vincent looked at MIRA for their speed record attempts, (the 24 hour record), but both found the cost too prohibitive, and went elsewhere.

The current HQ was completed in about 1954, and a wind tunnel - the first for motor cars - was opened in 1959. This was modelled on the wind tunnel used at Farnborough for aircraft testing.

MIRA have a web site which might be worth visiting - On the 'The MIRA Estate' section they had a historical pic showing an aerial view of the track as it was, and another as it is today. Unfortunately I do not have any photos of MIRA - but I'm reasonably sure that there would have been photos in the press of the day - 'Motor" for example, which can be researched on-line..."

The association does have a website and worth a look at...

http://www.mira.co.uk/about-mira/mira-heritage#timeline-milestone_142

M.I.R.A in 1956.....

White china clay similar to tropical desert dust, used for testing.

Smiths Industries tested waterproofing of instruments...these used on the Austin Champ 4 x 4 and Ferret Scout car.

As I mentioned, M.I.R.A is mentioned in Motorcycling road tests, so I've added some items from the "MotorCycling" Road Test series, between 1958 and 1961 ( acknowledgement to Morton's Motorcycle Media for these)....