1933 Model 40 Norton

Sent by Leonardo in Argentina

Leonardo is the owner of this Norton; it used to belong to his father who won a few races on this one.

Simon: "I looked it up in the Works Records. It's a Model 40. Engine number 24XX. Frame number 509XX. Gearbox: racing Sturmey-Archer 4-speeder, number 10796. Magneto Number 385920 (looks like BTH). Forks number  8989. TT Specification - tuned. Despatched 20/9/33 through the London based Export Merchants Agar Cross. This company dealt exclusively with South America so it is no surprise that this bike is in Argentina."

John: "The Norton has matching frame, engine and gearbox numbers. Note the racing goodies like the megaphone exhaust and rubber Dunlop saddle. It's a bit of a mess but very original. See the pic below; that front downtube had another shape when it left the Works!

1929 Model 16H engine - For sale

On Ebay; A 1929 16H engine.

1928 Model 18 Norton - SOLD

For sale SOLD at Ron's; not a bargain! Contact Ron directly, the Norton is not on his website.

Stanley Woods, 1930, Model CS1 Norton

-SG- This one, showing Stanley looking very relaxed, dates from late 1930, I think. Note two stay rear frame and - just about visible - downdraught carb. The man on the right is M. Psalty, the Norton distributor in France. The photo appeared in the VMCC magazine a few years back but this copy came from the Dennis Mansell collection via the late Peter Roydhouse.

A letter from Pat Driscoll

By Simon

Hayling Island is where Pat Driscoll lived after the war and where I went to see him in the eighties. Driscoll's memory was excellent but it was not clouded by subsequent years working on other bikes.  Basically, it was all Nortons only!  Although the direct question was not asked he gave no indication as to the extent of his involvement or the fact that he - as deduced by Roger in his book - basically did all the engine work for the bikes Nigel Spring ran at the track.  Oddly enough, I came across a letter (above) a couple of weeks back from Driscoll to do with a question I had sent him re. my Brooklands Coventry Eagle.  I must have also asked him a Norton related question because in one short sentence he confirms he indeed did all the engine work for Nigel Spring!

Regarding the mods Driscoll made - the long (8 1/2") con rod idea did not come from Driscoll. It was current practise at Brooklands and was almost certainly something emanating from the highly successful Chater Lea tuner and rider, W D Marchant.  This - conveniently - ties in with the fact that the 8 1/2" rods were made for Spring/Driscoll by Chater Lea.  Driscoll told me the idea was not so much to increase speed as to increase reliability as it reduced the angle of thrust on the crankpin and also - to quote him - 'reduced piston scuff.'  The selection of the 8 1/2 " dimension may have come from Driscoll or Spring or someone else.  Whatever, it was an inspired choice as it allowed use of the same high compression piston in either a 588cc engine or a 490cc engine, despite the 20mm stroke difference.  Other tweaks are more basic - the long dwell IT cams were, it seems, used as well as steel ES2/CS1 type flywheels.  There seems to have been no change to valve sizes although I expect they used better springs than those available to the public.  It may also be that thicker walled crankcases and cylinder bases were used but this, again, would be to improve reliability.  There is little doubt that LPD (Driscoll) was a whizz at balancing too and managed to make the Nortons turn over at high speeds for long periods with considerable reliability. Driscoll did not as far as I have ever heard get involved atall with the CS1s - this was all done at Birmingham for road racing with comrades Moore and Carrol.

Alec Bennett, 1927 Model CS1 Norton

Sent by Al

"This is a copy of an original photo I have of Alec Bennett after he won the 1927 TT with Stanley Woods to his left. This photo was given to me by my grandfather who was a great Norton fan who used to visit Brookland regularly pre war."

Simon:"That's Walter Moore in the Trilby hat and Jimmy Shaw slightly behind Stanley to the left"

Grandfather's c1923 Model 18 Norton

Sent by Al in the UK.

"This shot is of my grandfather (who was a great Norton fan who used to visit Brookland regularly pre war) and my grandmother on his Model 18 at Hayling Island, Hampshire sometime in the late 1920's. I wonder if PC 3978 is still around. (JdK: PC 3978 was issued from July 1921 to July 1923 by Surrey C.C. (currently Guildford). It probably is a 1923 model then. Quite sporty, note the narrow mudguards, open primary chaincase and open exhaust). I've been trying to get hold of a flat tank Model 18 for ages similar to his! I'm looking for a flat tank Model 18 - project / box of bits, or what have you ? I have a 1923 Sunbeam 500 sv Sports TT short stroke flat tanker, 100% original for possible exchange; the bike is MOT's and taxed with a rebuilt engine. (below)"

Anyone interested in a swap can contact John

1939 Model 30M Norton - SOLD

At dr George's site. George:"The ‘M’ denotes to “Full Manx specification”. The differences from a “Standard” International are: Paired down lugs on frame. Full wrap round oil tank (this one is a new alloy item). Larger petrol tank (this one is new alloy item, and slightly smaller). Magnesium crankcases, cambox, timing chest etc. Different flywheel and conrod. Hotter cams. Manx clutch, C.R. gearbox ratios. Conical front hub, with magnesium brake plate. Megaphone exhaust. And probably a few more variations which escape me at present."

"This bike was bought by Wilfred Caunce in 1939 to race at the Manx GP. The 2nd WW stopped all that, but Caunce hid the bike, to avoid it being commissioned for the war effort. He rode in the Senior Manx GP in 1946 and came 34th and the following year he was 40th, but there was a much larger entry in 1947. It is matching engine and frame numbers, original log book and V5C. Picture shows a replica petrol tank which will be replaced by the original. Totally rebuilt. Available when running in miles and road tests are complete. A rare opportunity to buy an original pre-war Manx with Isle of Man history and totally sorted."

1925 Model 18 - SOLD

It's that 1925 M18 again... For sale via this link; asking price 19.500 euro.

Stanley Woods, 1930, Model CS1 Norton

By Simon

Came across this pic recently - it's the admirable Stanley at the 1930 Senior TT  (in which he retired). One can see reasonably well the Best and Lloyd oil feed from the chain feed tank in front of the engine.

Model 21-25 oil pump parts - SOLD

On Ebay. Chance to buy a rare oil pump worm drive gear set and related parts which were originally fitted to a 1926 Model 21 OHV flat tank Norton, but which will fit also the TT Model 25 of the flat tank era. A similar arrengement is used on the early CS1 camshaft models and they may possibly suit this model or be modified to fit.

Dan O'Donovan on a c1920 Model 16H Norton

Roger:"The registration and the chain drive indicates a post-war event. From the registration and the riding number my best estimate is the 1920 Isle of Man TT where Dan was team manager."

Martin:"The interesting thing about this picture of O'Donovan is that it has a Leicester number. Look at page 62 of the Woollett book (above) and you will see the Norton camp at the 1920 TT. The bike at the front which isn't described in Woollett's caption belonged to Leicester motorcycle dealer Harold Petty and below is an extract of the Leicester county records showing the details of this bike which was finally scrapped in 1934, its last owner having had it attached to a sidecar, a sad end for an ex TT bike! .

Petty retired in the 1920 TT but Nortons did better than ever that year, coming 2, 4, 7, 8. 10, 11, 13 and 14, and four other Norton riders apart from Petty retired. 11th was Norman Black on the last Norton belt drive TT entry, a pretty good effort for his first ever TT ride, the start of a longish TT career through the twenties. The question I would want to ask about this picture is was this a Petty-owned (and hence Leicester registered) bike, and if so, why was O'Donovan riding it? I will get the entry from the Leicester public record office so we can see whose bike it was!! Possibly it was a bike ridden in the 1920  by a rider who retired and maybe D'Donovan rode it before or after the race, as he wasn't a rider himself by that time, his only TT rides being 1913 and 1914."

Update 05 July: I now have the registration data on this machine, and it was actually a 1920 4HP Model 1 (ie a Big Four) not a 16H at all.  That said, the machine pictured looks suspiciously like a 16H as the frame and tank of a Big Four are normally different around the steering head, so the mystery deepens.  What is certain however is that the machine was originally registered to Harold Petty as I suspected, the number dates from 1920 (19 May to be precise) and the machine is frame no 2530, engine no 20328, which is a bit earlier than the 16H Petty rode in the 1920 TT (frame no 2692, engine no 20389). Still no idea why Dan O'Donovan should have been pictured astride the machine, or what the race the number attached refers to...

As with all things to do with Nortons, the more you find out, the more you realise that nothing is as straightforward as it seems.

Petty's dealership was still active in Leicester until it closed in the 1970s.  I found a nice piece about them on another blog...

"At the top end of London Rd was Leicester's own Velocette dealer- Messr's Petty's. Here was a place where time stood still. The cut and thrust of business in the 1970's was not really for them. Customers were addressed as "sir" and the whole manner was more akin to a gents outfitters than a busy motor-cycle shop. Many of us called in on a Saturday afternoon, not to part with money, but to listen to "young" Harold recall the halcyon days of motor cycling. If anyone wished to buy something, Saturday Geoff was summoned, and the part required described in detail. In a scene reminiscent of Grace Brothers "are you being served" he would enquire if Hilda (who had an encyclopedic knowledge of all things Velocette) was "free". She would then fetch the part, place it in a bag for you, issue a till receipt and amend the stock records. 

Meanwhile outside Petty's the entertainment continued, with us teenagers gathering around to watch various motor cyclists following the starting procedure, or ritual, to bring a hot engined Velo into life. It seemed to us that the number of kicks to start a Velo was directly proportional to the number of people watching!! 

Sometime in the 70's Petty's closed, and the names, faces, and genteel procedures passed into motor-cycling folk-lore."

1930 valve lifts

By Simon

Regarding a previous blog on the Franks redesign of 1931, hereby some calculations on valve lifts; I freely admit I have not actually measured the lift of a valve in an assembled engine to see if the results achieved by calculations based on the measurements are - more or less - correct and perhaps someone should do so! Anyway, the details noted are:

Open push rod engines (1926 - 1929). Cam followers - contact point with cam 1.63" inches from pivot point; contact with tappet foot 2.037" from pivot point. Thus cam lift is magnified by a factor of 1.249. Rockers - centre of ball end to centre of pivot point 1.329"; centre of pivot point to centre of contact point with valve stem 1.476". Thus tappet lift is magnified by a factor of 1.11. Average cam lift on W7 inlet cam (they all seem to vary a bit) 0.290" so lift at valve is 0,290 x 1.249 x 1.11 = 0.402".

Closed push rod 1930 engines with standard cams (NB; not ES2 cams which have higher lift). Cam followers - contact point with cam 1.87" from pivot point; contact with centre of push rod socket 2.193" from pivot point. Thus cam lift is magnified by a factor of 1.172. Rockers in cast alloy rocker box - centre of ball end to centre of pivot point 1.528"; centre of pivot point to centre of contact point with valve stem 1.5". Thus push rod lift is actually very slightly reduced by a factor of 0.981. Average cam lift on 1930 cams 0.300 inches so lift on valve is 0.300 x 1.172 x 0.981 = 0.345".

The 1930 ES2 cams (marked E2720 and 2721) have substantially greater lift than the 1930 Model 18 type and have the same small base circle. The lift is 0.343" and use of these cams in a 1930 engine will increase the valve lift from 0.345" to 0.394".

I find it interesting that even with the sporty ES2 cams, valve lift on the 1930 engines does not quite match that of the earlier open push rod/W7 engines and there is such a big difference between valve lifts using the standard 1930 cams and the earlier set-up.

A CJ in action in New Zealand

Sent by Simon

Leading New Zealand aerial photographer V C Browne on his Moore type CJ, possibly competing on the beach at New Brighton near Christchurch in about 1938. Only four of these models in standard form were imported into New Zealand plus one rather special version with chromed tanks and an engine described as 'to Ulster Grand Prix specification'. Photo kindly provided by V C Browne's grand-daughter Kathy Shaw-Urlich, Whatuwhiwhi, New Zealand.

The Franks redesign of 1931

-SG- The Franks redesign which resulted in the 1931 range of production Nortons was not an unmitigated success! I have already mentioned my late friend Jack Bindley's experiences with his new '31 ES2. He was as disappointed with the bike as he was with Norton's response to his complaints. Last week I came across a few back numbers of the Beaulieu magazine 'Veteran and Vintage' and found further criticism therein from Richard Chapman, who worked for Eric Fernihough (amongst other well known people) at Brooklands in the thirties. Richard bought a new 1931 Model 18 from dealers in Trowbridge, to which, after careful running-in, he attached a new TT Hughes sidecar. He goes on to say..

"This machine was the slowest thing on wheels and a great disappointment. With the light TT sidecar and a passenger, the maximum speed was about 50 mph and after a while I rode the machine to Birmingham to see the makers about her. A tester took her for a run round the houses and reported that she was up to standard, which drew from me the comment that their standards must be pretty low! After a lot of postal haggling, Nortons gave me a set of what they described as 'dirt track rockers' (ie cam followers) for the crankcase and these improved matters a little. I then got going on my own and raised the compression. I increased the inlet tract bore, fitted a larger inlet valve and a 10TT25 carburettor. This, with stronger valve springs, rebalancing and some work all over the engine, improved matters. The final result was that I could get 80 mph with a passenger in the sidecar, under reasonable conditions."

Richard must have had considerable tuning skills - doubtless enhanced by later experiences with Fernihough.

Albert Hunger, on a Model DT Norton
at Kilbirnie Stadium  (Wellington, NZ)
ca. November 1930

The reference to Dirt Track Rockers is intriguing as the dirt track model (above) was only made in 1930 - not '31 - and it would be interesting to know just how the rockers differed from the standard profile. And there is a possibility we can find out: a 1930 dirt track engine bottom end has surfaced in NZ and although rather hacked about, I am encouraging the owner to take it apart and see just what is inside! So watch this space!

The decline actually seems to have started with the 1930 enclosed rocker box set-up. The geometry of this rocker box is such that the valves open less than the lift on the cams while with the open rockers they open more...And why did Norton dowtune these engines? My guess is that they were seeking longer term reliability. What else could it be? From a marketing (doubt if the word had been coined then!) point of view it was perhaps no bad thing to have the OHC machines as real flyers and the over the counter bikes as just reliable moderate performance means of transport.

Competition machine wanted

Sent by Howard

Simon: 

"This letter from Nortons is noteworthy from two additional points of view:

1. It is signed by GWW who was of course Graham Walker working for Nortons at the time.

2. About twenty years ago my next door neighbour was a nephew of Mr and Mrs Longman and he told me in no uncertain terms that he and the family were not too enthralled with the behaviour of one of Longman's employees, who, after Mr Longman died, was allowed to carry on the bike side of the business while Mrs Longman occupied herself with selling paraffin and charging accumulators (for radios etc).  Basically, they felt this chap - also now dead - took unfair financial advantage of Mrs Longman's good nature.  My neighbour also said that when Mrs Longman finally toppled off the perch, it took him and his cousins three weekends and several skips to clear all the motor cycle stuff which, he said, 'nobody wanted.'  This I find hard to believe as I believe Mrs Longman died in the seventies and there would have been plenty of people interested had the right contacts been made. As the saying goes, enough said!"

Jeff's 1927 Model 18 Norton

Sent by Jeff is Australia

"Here are some pics of my Norton. As you can see, it's incomplete at this stage."

1934 Model 30 Norton

Sent by V. Devis in Italy

This is a Model 30. It was checked by Annice and Michelle against the Works Records and it still has the original engine to frame. It was sent to Jordan, Hull, 8 May 1934. The specification is very hard to read in the records but it probably contains the word 'racing'.