Replica DT Norton

-SG- The dirt-track museum 'Cinder to Shale' in Scotland, has been brought down to Ledbury in Herefordshire where I understand it was auctioned last week. It is thought to have been the biggest collection in the world. 

One of the lots was a replica DT Norton built some twenty five years ago by Jim Gregory.  Not having an original DT Norton engine, Jim used an early 1930 Model 20 unit, which looks very similar. He told me that he never actually ran the bike before he sold it to Ian Paterson, the 'Cinder to Shale' owner.  And indeed Ian may not have run it either. Of course, the Model  20 engine will almost certainly have been used during its life but how much is open to query! It will be interesting to see if the new owner gets it going!

PS: ... sold for a hammer price of £15000 and the buyer, would you believe, a well known gentleman named Sammy Miller! Perhaps the auctioneers did not  know it was just a replica ...

1930 DT Norton in Denmark

 

-SG- Allan Sorensen sent me this photo a while back. It dates from the early thirties and shows what seems to be the only DT Norton shipped direct to Denmark - the dealer being a company called Petersen. 

The rider is Svend Aage Engstrom and the man standing behind the bike is Kaj Sorensen - eldest brother of the well known S A Sorensen and himself a Norton agent in Copenhagen.  Thanks to Allan for the photo! 

1930 DT Norton engine - For sale

-SG- Back in October 2018 we posted details of Alain's 1930 DT engine on the site. Like most of the known surviving DT engines it has seen various modifications over the years which are detailed in our posting. The engine (49112) started life as part of a complete DT machine imported into New Zealand in August 1930 by Whites of Wellington. Alain had hoped to find an original frame and parts to build a running machine but he says that is unfortunately not going to happen and he has decided to sell the engine. Offers directly to him please at ' recycledreading@xtra.co.nz ' . Incidentally he says he would have no problem in exporting the engine back to the UK (or anywhere else) at the buyer's expense and has access to reliable packers and shipping agents.

Bonhams Autumn sale at Stafford

 -SG- I was recently sent what seems to have been a draft text of the publicity announcement for this upcoming sale.  I queried one particular aspect of it with the powers-that-be at Bonhams and lo and behold! the text now seems to be as they intended!  I am not suggesting, let me hasten to add, that the text correction is anything to do with me!  However there are a couple of Nortons for sale for which the descriptions are either questionable or slightly inaccurate!

 

First - what is listed as a 1915 Big Four.  Looks very presentable but is it 1915?  The engine number begins with BA which indicates 1921 and although frame number information prior to 1922 is sparse it seems that the quoted frame number of 3370  also comes from the same year.  Other negative points re this machine - it has been fitted with a six inch front brake; a late thirties Amal carb.; and an early twenties gearbox and gear-change.

 

Second - the  sale includes the Forshaw speedway machine collection which has been at the Haynes Museum for the last twenty-five years.  This includes a 1930 DT Norton and during the mid-nineties, I had the pleasure of visiting Richard Forshaw and his father Ivan at their premises on the south coast and was allowed to see the machine during its rebuilding stage.  It is no longer fitted with its original engine but with a mid 1930 Model 18 power unit. which was fitted to it (albeit with a DT engine timing cover) when I saw it.  So what's wrong with the sale description?  Not a lot, really!  It states that only 11 1930 DT models were produced where the records show 36 plus various spare engines.  And there were twelve machines for DT use produced in 1929, but using Model 18 frames and forks. The comments re the gearbox fitted could perhaps do with a little amplification,  As originally fitted it was simply a countershaft but could be easily fitted with the rest of the necessary internals and gearchange parts to make the machine suitable for its later grass racing purpose.

PS. The supposedly 1915 Big Four fetched £12650 inc. premium and the 1930 DT machine with Model 18 engine £20,700 inc. premium.  Perhaps the buyer of the DT bike should also buy Alain's engine and then he would have most of the parts to make it more original! 

1930 Model DT Norton in the USA

 

-SG- Back in Nov 2013 Barry sent us an excerpt from the American magazine 'The Motorcyclist' of  Sept.1933 showing a seemingly standard 1930 DT Model.  According to the records only one DT Norton was sent to USA so it is reasonable to assume this was it!  Fast forward to last month and I am told a DT Head, Barrel, Rocker box were on EBay in USA  - incorrectly described as being parts from a Model 20.  The head has seen considerable damage to one of the exhaust ports and the fins are in need of repair ... Is this all that's left of the one and only DT machine to go to the States?

Model DT blueprint

 

-SG- Many thanks to Ian for these images relating to the 1930 Dirt Track Model. Strange that the date is shown as  June 1929 when the model did not actually reach the public until 1930. I have no explanation to offer!

Dirt Track Nortons in The Netherlands

-JdK- Dirt Track ("grasbaanracen") was somewhat popular in the late 1920s - early 1930s in The Netherlands with some of the riders competing on Norton machines. Above we see Arie van der Pluym on a 1930 Model DT on which he was very successful.

Below two photos of D. Sleeuwenhoek on what could be an AJS engine in a model DT frame/tanks/wheels (note the AJS caption and different exhaust pipe) and most probably on a  modified 1930 Model 18. Many thanks to Olav and the VMC for sharing!

1930 DT Norton

Three photos of the Triumph/Norton as found. There were a couple of wheels with it in a similar sorry state!

-SG-  Another DT Norton engine – regrettably somewhat altered from its original specification – has come to light in New Zealand. This unit originally started life in a complete machine shipped to NZ in the Autumn of 1930 and finished up fitted to a real ‘Bitza.’ One could almost stretch a point and say that it was a ‘Triton’ as it comprised a 1929 Triumph frame and forks, and 1929 Sturmey gearbox as fitted only to certain Ariels in 1929/30. It had apparently languished in a damp cellar for many years before being bought by Alain.

Five general photos of the engine before dismantling, after a soak in diesel for several weeks.

Alain kindly brought the engine for me to have a look at earlier this year and we succeeded in partially dismantling it. Final dismantling took place a few weeks later, thanks to the loan by Viktor of his timing pinion puller.

Apart from the fact that the original timing cover had been replaced with an earlier ES2 cover the engine looked fairly original externally, with only minor repairable damage to the lugs at the bottom of the crankcase.

Various shots of the engine taken during dis-assembly.  Note bob-weight polished flywheels, long holding down studs for head and barrel, flange mounting for carb., twin exhaust ports with internal threads, large spigot on upper face of barrel and corresponding recess in head, piston crown with unrecognised markings.

The flywheels fitted are polished and of the bob-weight type, which came as a surprise. This is because the only other DT engine of which I have seen the internals has flywheels without bob-weights – more like those fitted to ES2s of the period but with 22mm mainshafts both sides. However, those fitted to this engine are assuredly of 1930 type and have a drilled timing side mainshaft for positive big end feed, Perhaps, therefore, both types were fitted to the production DT range but until we can find out about the internals of some of the other few survivors, it remains a matter of query.

Cam gear showing earlier (W7) cams and spacers to achieve alignment with followers.

Another difference on this engine which I feel probably dates from when it was built into the road bike, is that the original small base circle cams have been replaced with a pair of pre-1930 cams. These have been fitted with small steel bushes on either side of the spindles to ensure they are correctly aligned to operate the seemingly standard 1930 type cam followers.

Both head and barrel look in excellent condition – the head having twin exhaust ports with internal threads for exhaust pipe nuts as pictured on previous postings. And finally, the piston, lightly domed and with three compression rings, has numerous letters and figures stamped on it, none of which I recognise!

Ian has been in touch re the unrecognised piston markings in this engine - his message - for which many thanks -  is below. It appears the CY80 numbers on the crown show it to be intended for 1931 CS1s and Models 18/20, with a 7/8" pin.

"The attached scan from the 1936 Polson list may help. The piston was made by the Polson Motor Parts Co of 172-180 Berkeley Street Carlton N3 Victoria (an inner northern suburb of Melbourne just outside the central business district). The copy came out of my 1936 Polson catalogue and no further reference  is made to these 'all compression ring' pistons in my subsquent 1953 and 1960 catalogues."

I have been asked for confirmation of how the magneto was driven when the engine was built into the Special - a suppementary sprocket brazed to the inside of the engine sprocket is the answer - see photo!

DT Nortons - the fore-runners

-SG- On 27 July 2015 we had a posting about E O Blacknell (the Blacknell Sidecars chap) and his Dirt Track Norton  which, from the photograph, appeared to be 1929 Model 18 based, albeit with no brakes. Now, thanks to Alain, Alan, and Peter Thomson, all in NZ, we have some brief but relevant information about the DT Model 18s and ES2s which preceded the production DT machines produced in 1930.

Scans from the now comparatively rare magazine produced in the twenties and thirties entitled New Zealand Motor Journal have come to light and are attached (below). The photos only show the Model 18 based machine and it's worth repeating what E O Blacknell recalled - that the cams on his engine could be unscrewed from the cam wheels. As a result of this, it is my view that the power unit in the Model18DT was basically '28/29 ES2 (which used this type of cam wheel) but fitted with a timing cover very similar to the regular 1930 type. The gearbox shown in the photos in the article is not - from its appearance - an LS type, but the rather unusual racing three speed CS box which we have talked about before (see posting of 25 July 2015).

(right-mouse-click, open in new screen for a large version)

Model DT Norton

-SG- John has come up with this snap of Frank Varey on a dirt Norton in the early thirties.  Thanks!

Dirt Track Nortons - yet more!

-SG- Few are known to exist and of the few which do, it is far from clear if any of them is, shall we say, '100% genuine.'

The Haynes Museum bike - which came originally from the Netherlands and is on loan from the owners - has what appears to be a Model 18 engine in most respects. The machine in Ian Paterson's Cinder and Shale museum in Scotland is a replica put together in the nineties although part of the frame may be genuine. Ian's model, down in Devon, came from the Cinder and Shale collection and seems to have a Model 20 head but Ian has kindly said he will make a note of the engine number when it is next taken down from the shelf in the building housing his collection of over sixty Nortons.

Then there is another in the Netherlands - of which recent photographs are attached above. Here again the engine seems to be composite - 1930 Model 18 crankcases and 1930 Model 20 head. However it appears still to have the original special CS gearbox which has been the subject of earlier postings.  Let me stress that DT flywheels will fit straight into the 1930 Model 18, 19 or 20  crank cases and it is of course possible that any or all of these machines still retain original steel flywheel assemblies. However, the magneto chain cover was considerably shorter (more than an inch) on the DT engines, a feature I think visible on only the the Haynes bike and 'Cinder and Shale' replica.

As far as surviving engines are concerned, there appears to be two (not complete) in New Zealand, one I have recently heard of in Australia and one, possibly two, here in UK. I say 'possibly two' in UK because the then owner of the Haynes bike also had most if not all of a genuine engine as well.  After his unexpected death at an early age, his widow had a visit from someone offering to 'clear out' his accumulated motor cycle stuff of which she had no need. The DT engine was part of the lot and it is not entirely clear if this is the other known UK engine or yet another.

If anyone has any more input on these rare Norton models, please get in touch!

1930 Model DT Norton

-SG- Leon is Australia has forwarded this photo of Herb Durkin - about whom there's a fair amount on the Internet, worthy of a quick read - seated on a 1930 DT Norton. The photo is via the Herb Durkin Collection of David Dumble in Melbourne. I was on the point of mentioning that only one DT Norton shows in the records as having been sent to Australia when I had another look at the photo - from which it seems quite likely that it was taken in New Zealand where perhaps Herb was on a visit at some time.  Be that as it may, the photo shows quite clearly the through bolts holding head and barrel to crankcase  and, not quite so clearly, the hexagonal exhaust nuts threaded into the exhaust ports, both features of the production DT Nortons.

Alec Pratt, dirt track Norton

-JdK- This is Alec Pratt on his dirt track motorcycle at Kilbirnie stadium (Wellington, New Zealand) in November 1930. The engine is a late 1920s OHV Norton. The frame doesn't look like the Model DT frames. (Photo from The National Library of new Zealand).

-Steve- The Norton engine has been fitted into a 350cc Harley Peashooter frame of around 1928 vintage; see above.