Norton 1947 B3T questions

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I recently come across an almost complete lower engine case on Craigslist for a Norton. It was listed as a Triumph. But after I went to look at it I just knew I had to have it for the sheer coolness of a pre unit single cylinder! I brought it home knowing it wasnt a Triumph engine. So I began searching the great WWW and was able to identify it as a Norton. Now I am reading and have become very confused as to what it is exactly. This is what I have gathered from one piece I have read. And PLEASE correct me if I am wrong (this is why I am posting this) that the Norton B3T was a Trials engine or prototype that later developed into the 500T. Now the fun part PARTS!! I have seen cylinders marked from sellers as AJS Matchless Norton. Are some or the Brit motorcycle engine parts interchangable? Can somebody please help? I cant figure out how to put a pic up on here!!!
 
no, the engine parts are not interchangeable unless the particular company used engines from another marque,
I dont believe AJS/Matchless and or Norton did this with their singles, especially yours in particular, You will have to identify exactly what model you have and search for parts accordingly, it can take some time but its all part of the fun of restoration projects.
 
madass140 said:
no, the engine parts are not interchangeable unless the particular company used engines from another marque,
I dont believe AJS/Matchless and or Norton did this with their singles, especially yours in particular, You will have to identify exactly what model you have and search for parts accordingly, it can take some time but its all part of the fun of restoration projects.


Norton ceased making the trails/road singles long before they moved from Bracebridge Street factory to the Plumstead factory, so, apart from the Atlas/early Commando powered 750s town and jungle bikes, (Norton/Matchless hybrid labelled the P.11), never in the case of the 500 single, did the twain officially meet.
That is not to say that someone with all the parts making their own Bizza from them.
 
http://www.nortonownersclub.org/history ... 954-trials

350 / 500 TRIALS


For the never implemented range for 1940 Norton had intended to offer a single trials model with either 348 or 490 ohv engines. It was to be based on the rigid ES2 frame and it is surmised that the three ES2 machines used by the Army in the 1939 ISDT were prototypes. The 'works' bikes built during 1945 followed this approach, had a short wheelbase rigid cradle frame, International type rear tank lug, Inter girder forks, WD adjustable handlebar clamps, WD rubber bump stops, some had the Manx 8" cone front brake and 21 x 3 and 18 x 4 inch Universal tyres. The petrol tank held just over 2 gallons and the engine was based on the standard Model 18 motor, but was fitted with an alloy Inter barrel and the alloy head developed for the 1938/39 bikes. Ignition was by either BTH or Lucas racing magnetos. A high level exhaust system with a 1937 type silencer was fitted. The gearbox had wide ratios and a folding kickstarter. The 350 used an 18 tooth engine sprocket, whilst the 500 had a 20 tooth sprocket. Racing clutch and brake levers, reinforced steel mudguards, short footrest hangers with the tubular footrests adopted from the WD machines completed the ensemble. The 350 utilised the 500 crankcase, but mainshafts were 25mm dia. as prewar. For the 1947 season these bikes were fitted with teles and the frame was extensively modified. The front down tube was shortened by 1.5" and some curious bends incorporated in the front down tube and tank rail to provide a more upright steering head.

At present six bikes are known to survive, the Billy Matthew's D30T in Canada, three 500s (1 No. A3T and 2No. B3T) and two 350 (Bl3T), one being Ted Breffitt's machine.


500T


A return to the open frame Model 18s used in the immediate pre-war years was the basis for Rex McCandless's reworking of a WD 16H, with a short wheel base and fitted with reinforced alloy mudguards. the alloy version of Norton's 1938/47 engine was retained. The fork yokes were revised to bring the fork stanchions nearly parallel with the steering head and a light gauge steel petrol tank with single bolt attachment provided a unique feature. originally painted in the manner of a Manx tank, production machines had a dull plated finish. Massive steel footrests attached to the bottom of the alloy engine plates had been the work of Terry Hill. A low level exhaust system ran the pipe under the engine timing cover. The front brake had a 5-1/2" drum, but when production models appeared, they had the road bikes 7" drum, extensively lightened and fitted with an alloy brake plate. An alloy version of the redesigned 1948 engine was in use on factory and production bikes by the year's end. Standard gearing was 5.6; 8.3; 13.15; 18;5. A BTH KD1 magneto provided the sparks.

After its debut, the production model received very little development. Chrome shortages saw paint finishes on tanks and rims. The gearbox end cover was modified to make it easier to change the kickstarter spring and the Wellworthy Company produced head and barrel using their patent AI-Fin system, which had originally been developed for aircraft engines. An 8" front brake was fitted in 1954. Other companies continued to improve their machines and 1954 was to be the last year when rigid framed trials machines were campaigned by the major factories. AMC were on the point of introducing their own sprung trials machines and saw no point in Norton taking a slice of the market.

Twenty five 1954 models were built, these terminated the production run which between 1947 and 1953 had seen a total build of some 850 machines. It is thought that nearly 200 still survive.

Also

http://www.bonhams.com/auctions/18294/lot/221/

1952 Norton 500 Trials
Registration no. ANC 707A
Frame no. G443714
Engine no. B3T 13350
Norton's post-WW2 trials campaign got off to a false start in 1947 but after a season of extensive modification and experimentation the factory came up with the legendary 500T. Shortened rear frame stays and a modified lower fork yoke reduced the wheelbase to a more-manageable 53" while an alloy cylinder head and barrel helped reduce weight to around 300lbs. Numerous works and privateer successes soon confirmed that Norton had produced a machine as good as, if not better than, any other rigid-framed trials iron.

Offered without reserve, this collection of parts represents the basis of a highly desirable classic trails bike. It consists of a Norton 16H frame modified to 500T specification; a 500T engine; a 'doll's head' gearbox; long Roadholder front forks; a fuel tank; alloy engine plates; a front brake back-plate; a rear stand; two new Dunlop Trials Universal tyres; and a box of miscellaneous parts. There is a Swansea V5C registration document with this Lot.
Sold for £2,300 inc. premium
 
The engine case is marked B3T 8167 79x100 1947. Is this the same as a 500T? If so what years will fit. Need a cylinder barrel and cylinder head.
 
Norton trials bikes used iron cylinders and heads before they went to alloy bits, so any ohv 1947 or earlier head and cylinder will probably fit it. Appear now and then on fleabay, but examine carefully, they are not always in pristine condition. Don Morleys excellent book on old trials irons mentions riding such a heavy beast ! Apparently they did surprising well.

The alloy bits appear now and then too, but expect to be in a bidding war, they are somewhat sought after.
And a lot lighter....
Not sure if they were available in 1947 anyway.

So do you have a bike to put it in ?
 
Bernhard said:
Norton ceased making the trails/road singles long before they moved from Bracebridge Street factory to the Plumstead factory, so, apart from the Atlas/early Commando powered 750s town and jungle bikes, (Norton/Matchless hybrid labelled the P.11), never in the case of the 500 single, did the twain officially meet.
That is not to say that someone with all the parts making their own Bizza from them.

Irrelevant here in this context/thread, but Norton singles were made right to the end of Bracebridge St.
And the Norton ES2 and the Matchless Model 18 in the mid 1960s were then identical except for the badge.
So the twain did officically meet.

Check your facts BEFORE posting ??
 
Suggest you speak to Mike Pemberton, he may be able to help, he is doing new alloy barrels.

http://www.pushrod-performance.co.uk/

Lightweight Aluminium Barrels for Long and Short Stroke Engines

The plan was to initially produce three engine sizes.
84mm X 90mm. This was a Norton Pre-war experiment.
85mm X 88mm. This is the famous BSA Goldstar dimentions.
86mm X 86mm. This is What is commonly refered to as a square engine, that is the bore is the same size as the stroke.
I have now realised that the Classic Trials enthusiast does not want a hi-reving short stroke engine.
The fourth variant will be a copy of the famous 500T barrel with dimentions of 79mm bore to be used with a standard 100mm stroke crank.
 
Use caution here though, the 47 engines are different to 1948 and later.
Nothing much interchanges - unless its made to fit ?

Without an alloy head, an alloy cylinder is about as useful as a fish with a bicycle too...
 
Hi All, this bike isn't a 500T it is the 1947 production trials machine which is pre the 500T. It has iron head and barrels and a cradle frame, unlike the 500T.
Here's a picture and you can see it's very different from a 500T. The 500T was made from 1949 - 54 and had the different engine with the wider valve gear, as Rohan has mentioned.

Norton 1947 B3T questions
 
OK Rohan, I stand corrected;
The last Norton ES2 was produced in 1964, but a Matchless-based machine with Norton badges was produced for two years before final discontinuation, coincident with the commercial failure of the AMC Group.
 
This means you could still buy an ES2 new in the showrooms until 1966, does it not ?
And with Norton wheels, forks and badge. And a short stroke engine....

Apparently, being a hybrid, they were loved by no-one.
But were quite a good machine.
 
Horror said:
Hi All, this bike isn't a 500T it is the 1947 production trials machine which is pre the 500T. It has iron head and barrels and a cradle frame, unlike the 500T.
Here's a picture and you can see it's very different from a 500T. The 500T was made from 1949 - 54 and had the different engine with the wider valve gear, as Rohan has mentioned.
]

Good pic horror.

Don Morleys books note that the trials machine, and then the 500T, although not shown in the catalogs, could be ordered as a scrambles machine.
Wonder what the difference(s) were.

As an interesting aside, the lower fork legs (sliders) in that pic you show were steel, with the chromed little top band.
Very distinctive 1947 feature.
And stronger than the subsequent alloy sliders. Much heavier too...
 
Good pic horror.

Don Morleys books note that the trials machine, and then the 500T, although not shown in the catalogs, could be ordered as a scrambles machine.
Wonder what the difference(s) were.

As an interesting aside, the lower fork legs (sliders) in that pic you show were steel, with the chromed little top band.
Very distinctive 1947 feature.
And stronger than the subsequent alloy sliders. Much heavier too...

The 500T could be ordered to "ISDT" specification according to a now deceased contact who had orded one as such from new and said that appeared on the factory shipping documentation. This included Q/D head and tail lights, a magdyno and a Terrys road style seat all of which were fitted to his. My as yet unrestored and a little sad 500T appears to also be of the specification. The headlight brackets are pressed tube similar to that used on a Goldstar BSA.
 
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