1931 Model CS1 Norton

 

-JdK- We've been contacted by Olof who is looking for the dimensions of a positive stop mechanism for his 1931 CS1 Norton.  It has a three-speed Sturmey Archer box fitted. Please contact us when you can help. His story is as follows: 

"Above a picture of my bike probably short after the war around 1946-48. It had been resprayed Maroon red and the wheels in Ivory. The CS1 started as a racing project in the early 70s. After the original fenders were found in an attic, it was suddenly an almost complete original bike. That's how it came into my possession but dismantled down to the smallest detail. 

I first test-drove it in 2015 and found it very pleasant to ride apart from the original Norton oil leaks from the cam housing and the annoying gear mechanism (below). One detail that has made both previous owners and me wonder is the many satin chromed small parts. Screws, nuts, footpeg details and fork links. They look to be Norton factory quality, mysteriously.

Otherwise, I discovered during the work that the rims and lamp housings are date stamped 1930. The rear hub is Enfield with original spokes but new nipples and the front hub is Horton with new spokes and nipples. The original saddle is still there but not mounted. The front fork is Norton's own with numbers according to the factory information.

According to the factory it was equipped with foot change. For the moment I use a TOR aftermarket mechanism. This is rather clumsy. I have managed to get descriptions and spare part pictures of the SA positive stop mechanism but no dimensions. I would be very thankful if anyone could assist with the dimensions. My workshop is quite complete and I believe that manufacturing a replica is entirely possible."

1928 Model CS1 engine - For sale

 

-JdK- Kyle in Australia is looking selling his 1928 CS1 engine, in his own words: "It has all the main components but would need a complete rebuild. This engine was delivered to New Zealand, dispatched 9 February 1928. It was a spare engine for a Mr Syd Ayling of Invercargill,  he had a CS1 he raced and was an acquaintance of Burt Munro. My father purchased the engine off the family in 2013. It is in very nice condition, it will need a repair on a lug casting. Located in Brisbane Australia. $ 11,000 AUD or best offer." 

1924 16H Norton

-JdK- From John: "Gday Simon and John. Have recently finished this 16H, a largely mechanical only restoration. This bike was featured by Rod back in August 2013. I acquired it from him a few years ago."

Model 24 project

-SG- Adam is making progress with his 1925 Model 24 project and is seeking a 5 inch front hub - has anyone got one to spare? Please let us know.

Two Nortons and a REX/JAP

 

-SG- I have known Juris Ramba in Latvia for about thirty years and I would say we are good friends.  Over the years he has provided plenty of useful information as well as lending me his Model 25 to participate in the Latvian rally a few years back. Here is a recent message and photos from him which we feel are worth posting.

"In the beginning of September my two sons and I went to the Polish fiva world motorcycle rally. Robert took our 1926 Model 25 and Reinis was on our 1930 Model 18. The Model 25 engine had been fully rebuilt with a newly cast cylinder which I bought in Britain and we machined it at our workshop.

The piston had been cast in Slovakia, the crankpin was bought NOS from a standard Norton and oil ways were erosion cut in it at a local factory. As the old crankshaft had been extensively hammered and out of alignment by 0.30 mm, we decided to make a new crankshaft from scratch. The webs were machined from heat treated steel billets fully adhering to the original measurements, even down to balance drillings. After assembly and testing the run-out which was 0.02 mm the balance factor came out to 67% which is quite good. The engine does not vibrate almost.

The shafts were made from case hardened and tempered 3 % nickel chromium steel, these were ground to 0.04 mm oversize. I bought a liquid nitrogen container from China, filled it up and used to shrink the shafts in cryogenically. To avoid any possibility for the shafts to turn in the webs, holes were erosion cut partly in the shafts and partly in the webs and pins were pressed in to safely secure these. The original drive side shaft had turned in the web in the past, so we chose to be safe rather than sorry.

One new intake valve was cut and machined from a Chevrolet valve which is nickel steel, with chromium plated stem. That was bought from the US. Then we had a look at the plunger oil pump. Its body was hard chrome plated and ground on the od. The inner plunger was made new, tempered and ground to size in our circular grinding machine to obtain minimum clearance in the bore. The old plunger had worn and had a running clearance of 0.04 mm which would not work with hot oil. We got the running clearance  down to 0.005 mm or so. The pump now works as it should and I am happy we paid attention to it, otherwise all the efforts and new parts would be in vain if the pump did not deliver enough oil to the engine components…

Finally upon assembly i found that the roller bearing central sleeve was too tight in the bearing. So i put it in the lathe and ground down 0.02 mm with fine abrasive paper. Thus i avoided seized bearing… 

I measured the crank end play with a piece of plasticine and a shim.

Robert had done 300 kilometres of running in before the rally, going out with the  M25 on early mornings before the summer heat came in. One day the inlet valve spring on model 25 broke. We did not want to take off the cylinder head to replace it, so the old spring was cut with an angle grinder in pieces and removed  and another old spring was fitted. I immediately ordered a batch of new springs from Alberta springs in the UK.

The distance at the rally was 420 kilometres. All 3 machines finished the whole distance."

Use 'em! The long ride 2024

 

-JdK- Each summer Rob and I take a longer ride on our Nortons, We've been to the UK, Scotland, Ireland, Central Europe. This year we joined the BOM rally in the west of Belgium but when all the others returned to the Antwerp region we headed for the Alps. 

In the past years we took our side valve Nortons, this year it would be different as we prepared our cammy Nortons, a 1931 CS1 and a 1932 M30. We've had these bikes for many years, they've seen a lot of work and modifications and we agree these are not the most practical bikes to take on a tour like this, most notably, it's more difficult to take luggage or spare parts, they can be pretty nervous in the unavoidable cities and the gearing is just not correct for climbing steep mountain passes. 

Anyway, it was a lot of fun. We spent a few hours in Belgium fixing a positive stop mechanism and the M30 burned through six liters of oil but for the rest they needed no more attention than some light fettling. We did around 2500 km in eight days riding from the Netherlands into Belgium, Luxembourg, Germany, France, Switzerland, Austria and Italy; the map above was recorded by my Beeline SatNav. In case you are wondering, we did use the night train from Innsbruck to Dusseldorf for the ride home.

Use 'em! Our Inters

 

-JdK- Spent the weekend riding our Inters. All three are pretty non-standard but it doesn't matter at all, they go very well. Very few things are more enjoyable than racing three Inters through the north of Holland on a sunny Sunday morning.

1931 CJ Norton engine

 

-JdK- An email from Frank: "I bought this 1931 CJ engine from a dealer in the Netherlands last summer. It originally came from a millionaire in Germany. The motor has been cannibalized over the years. Initially, it was supposed to go to someone in England, but the deal fell through. The buyer wanted to take it apart, but the dealer did not have the right tools and the piston was stuck in the cylinder. I spent 2 weeks to get the cylinder off. It seems to be a non-standard engine with a high, domed piston and a head made of bronze. There are oil scrapers fitted in the cases close to where the crankshaft runs. The crankcases are being repaired now. The crankshaft is ready. I have found and bought some parts already in the meantime. I still have an empty cambox ... Before I go screaming to Molnar for an oil pump, I would rather try to find a good, usable original Mazak pump. If you have one that you are willing to sell to me, please contact this website. Greetings from the Netherlands, Frank Kuyl."

The power of advertising

-SG- ... was more than apparent in the thirties - see attached Castrol Oil scan of Freddy Frith and Jimmie Guthrie from about 1936. Thanks to Adam for the image!

1936 Model 19 Norton

 

-SG- John has sent us a photo of his latest 'in use' Model 19 - a 1936 'bitsa' version which he says goes very well and - mostly - starts first kick!