31 Model 20 tank lining?

Roy Bacon's book " Norton Singles " lists the following:

"Standard models in the 1930's had silver tanks panelled with 1/2" black outer and thin red inner lines , also black rims and chrome fittings.Some had chrome tanks and then the petrel had silver panels but not the oil which was lined on the chrome, all lining remaining at 1/2" black and thin red. With this finish the chrome fittings would continue plus chrome wheels with black centers lined in red "

Hi Ian,

   The tank finish varied through the 1930s and different models. The bike in the picture looks  correct for 1931, but you should check this site for original photos, not restorations.

www.vintagenorton.com

The pin striping goes back to the earliest Nortons. It might get worn off in patches but it would have been there. In your year it was on the silver inside the black. The oil tank was similarly lined.

.......here:

https://drive.google.com/file/d/0B_5ev0g65Xk6VGg0LTVnUm4ySGM/view?usp=sharing

I am beginning to have doubts about the accuracy of my own post " Roy Bacons Book " etc after viewing the catalog that Mike posted and other photos as well. The black lining seems to be much larger than 1/2 " . It would be wise to compare the line in the photos to an object of known size on the bike in the same photo to make a more accurate assessment.

That looks like an Inter tank. They were not the same.

The vintagenorton site might assist..

However the shape of the 'teardrop' of silver paint seems to have changed right through the 30's if the artist's impressions can be believed. As Ian has found, it's not easy to find good pictures of exactly what you want.

scroll thru previous link.

Mike

Hi again Ian,

   The catalogue illustrations were artist impressions of the bikes for the new season but were drawn weeks or even months before the new specification was finally decided. This can often mean the tank finish or other detailed parts can be different on the actual bike to the illustration in the catalogue. There were never any actual photographs used of the new machines in that season's catalogue as they hadn't been finished before the print deadline. Although Roy Bacon's 'Norton Singles' is one of the better books, none are 100% accurate and you need to double check , if possible, with original machines or pictures. Even then there were sometimes mid-season changes or modifications, so unless you were actually there, nothing is written in stone!

.....and looks like it may well be:

http://www.vintagenorton.com/2013/09/1931-model-20-norton-for-sale.html

Faint red striping can still be seen.

I found this picture on the Internet- claims to be an unmolested 1931 Model 20 and it certainly appears that it is given its patina.

vestiges of the Norton script can be seen on the painted tank panel while the rust clearly shows that the petrel tank and oil tank were both chrome. As Roy Bacon stated , the oil tank clearly has no paint work other than the black and red lining.

Most importantly regarding the original question the black line width can certainly be extrapolated by comparing, for instance, the bolts/ nuts on the link of the girder forks. If you know the distance across the flats of these fasteners it becomes a relatively easy task of establishing a ratio by comparing the bolts/ nuts with the black line on the fuel tank - both of which are clearly seen in the image .

Hope this solves the puzzle - Richard 

Ha - It appears that Mike and I are on the same mission as we both found an image of the same bike at the same time - tip of the hat to Mike then - He got there first !

Max's Norton has been played about with to some extent. The oil tank has lost its paint.

I do know that the black panel line on my 1937 oil tank was originally 1/2 inch wide. I measured the shadow it left because the chrome had all corroded away but the tank metal was better protected where the black line had been. Photos show the tank line to be the same width (apart from the optional Inter tanks). And earlier tanks have the same width line but different shape.

The interesting thing to me about the spare part illustration is the way the panel lines taper together to meet just above and below the threaded hole for the knee pad rubber. Later 30s bikes had the lines stopping at a painted arc to follow the front curve of the rubber pad. And by the 40s and 50s the painted panel was a bit deeper again.

I can't see a white line. There is a narrow sliver of silver (about 1/2"or less) inside the black between that and the red pin stripe.

The other interesting thing (to me) is the top surface black panel. I wonder which year that appeared and then reverted to silver or chrome?

The line appears to be just about the same as the distance across the flats of the fasteners at the dogbone link on the girders - also close to the height of the capital N in the Norton script on the mag chain cover.

I also note the apparently black panel on the tank top - an anti -glare feature perhaps ?