1936 International

Hi Ian

I have a '36 500 inter to full manx spec. Well actually itâs a '35 chassis with a '36 engine in it, but they didn't change much from year to year. I believe in the day they referred to it as full 'TT' spec. As you said, 'manx' didn't come along until after the war as far as I know. I have never owned another inter to compare it too, and have only just stripped mine, so I don't pretend to be an expert, but the differences I know of on mine are as follows:

Central feed cambox lubrication

'Manx' big end (It is narrower and bigger in diameter I believe. Ian Bennet does a very nice needle roller big end to go in them if you need one)

I am told the flywheels are different but I don't know what the difference is...

Alloy barrel and head with a bronze insert in the head

Higher compression ratio, though I was unable to find a high comp piston so went for a normal road going inter one, I doubt I would notice the difference anyway!

The crankcases donât have the flange on the outside for the primary chain case as racing bikes had open primaries

Extra breather at the bottom of the bevel arrangement

Mine has rear set footrests instead of going through the engine plates and a wrap around oil tank with a longer filler neck on the left hand side.

I don't know anymore about the chassis as my bike came as a basket case with just the main bits there so things like mudguards and stays I had to source or make separately so I can't guarantee how accurate these are to original spec. I just did the best I could with pictures I had and original parts books etc.

Iâm sure I have forgotten something and if I think of anything else I will let you know. I am sure there are other people on here that can help you in more detail, and I stand to be corrected if any of what I have said is wrong.

Do you have the complete bike? Any pictures?

Hi Andy, reference your what's different question, possibly add magnesium crankcases, gearbox w/out kick start facility, camshafts, l/h filler on oil tank, lightened frame lugs on front down tube, large capacity fuel tank, forks without damper, black high tensile wheel rims, short front mudgaurd, open exhaust pipe plus more detailed differences.

Hi

I believe the 1936 TT inters where all ally crank cases. I have read that they where made to this spec for only a very short time before going to magnesium. You have a very nice bike there Ian!

When Mick Woollett published his great book on Norton and it's racing history, he acknowledged the help of a few Norton factory men, one of them Peter Roydhouse. NOC member Phil Hannam has the Peter Roydhouse archives now and is slowly getting through them and uncovering many interesting things. One of these is a letter from Roydhouse to Woollett thanking him for the complimentary copy of the book and offering corrections for some of it's pages and some comments on various Norton bikes including this one:

This suggests that there were Norton internationals and the well-known list of options which Woollett included in his book, and then there were true Works GP racers made from special racing parts most of which were not interchangeable with the International at all. The Norton GP racers had different frames, engine castings, tanks and other major parts that were never options for the International. If you have a 1935 or later OHC bike with the raised engine mounting, then it is not an International, it is a GP bike built for racing only by works or favored privateers, and a pile of parts much more rare than the rare International roadster no matter what options it has been dressed up with.

Hi Ben

I have a 1936 engine as you describe with the raised engine mounting under the barrel, no valance for a primary case and no tell tail. It also has different flywheels, big end and conrod to a standard inter. When I first bought the bike I got the records from the NOC and it came back as a '1936 international to full TT specification and race tuned by the factory' (I can't remember the exact wording but it was something along those line, and definitely had the words inter, TT spec and race tuned in it).

Unfortunately it was split from the rest of the bike at some point in its life so I am building it with an inter frame (has rear sets but don't think it's a racing frame) and girders off an ES2. I have the full wrap around pie crust oil tank with the extended filler out to the left and a large pie crust inter tank.

Although it would be nice to say it is a GP bike, I think I would have to be the first to admit it is now more of a Norton to 'full Andy spec' as I made a lot of the bits myself and sourced stuff from all over the place.

I would deffinately be interested to know more about my engine though if you can offer anything?

Thanks

Andy

Well make sure you don't attribute any quotes of Peter Roydhouse or other factory employees to myself. If you do not have Mick Woollett's book or Mick Walkers book on the Manx it would be a good idea to get your hands on them as they are very interesting with many photos.

My Manx is a 59' and not too pertinent, but I have one close friend with a matching-numbers 47' and another with some pre-war ohc bikes which I will talk to for you.

Woolletts book has the list of options and upgrades for the International in 1937 along with a old factory picture of an International to "Racing Specification" . So Peter Roydhouse may indeed have been mistaken on at least that point!

The picture in Woollett's book though does not show a bike with the GP style crankcases which your engine has.

Of course many privateers with or without factory help entered Norton Internationals roadsters in competition. If you look at all the books and photographs in these and other books you can find showing pre-WWII Norton racers, the only guys you will see racing the bikes with the crankcases like you have will be photos of either factory riders or those with close factory ties and sponsorship.

It would have been to Norton's and any other factory's benefit then and now, to show races being won on machinery like that available on dealer showroom floors, but that does not mean that the bikes the big stars were riding were available to the general public.

I believe the engine you have is worth tracing the history on back through previous owners as far as possible. Woollets book sets the production of the 490cc International for 1935 to be 172 units, which would probably be representative of the era. Bikes with racing crankcases like yours would be made in much smaller numbers for important riders and races, so it is a very important piece of history and you are lucky to have it.

So there were roadster Internationals tarted up with options listed as racing spec bikes, but in my opinion your engine is something more than that, it is a GP engine never meant for sale to the general public. Norton did this throughout it's history, racing and testing "works" parts that were not on production bikes right up to the time is was closed up at the end of 1962. The lighthouse cam drive appeared for testing on factory entered Manx bikes before it went on the 59' Manx for instance, and also there was the Domiracer in the early 60s that was chock-full of special parts that roadsters never saw. The 54' and earlier featherbed GP racers had all or few parts that would fit on a production Manx of the same year.

That is about all I have for now....

The records I have of the engine reads:

DOD 18.1.36 Engine 63077 Model 30. Gear Box 4696. Fork 18654. Extras. Built to Manx Spec. Tuned engine. Agents Layton's of Oxford. First owner not listed.

I got it from a guy who buys and sells a lot of bikes and had had it lying around for a while. That's about as far as I got tracing it backwards so I guess it may remain a mystery.

I talked to my friend in Canada who restores OHC Nortons and he backed up what I thought, that there were three tiers to the cammy Nortons in the thirties. There was the production roadsters with lighting and standard equipment or the performance options listed by Norton, then there was the roadster to racing spec that Joe Public could buy already put together with some or all of those options and stripped for competition, then there were the factory bikes that were not sold, just used by the team and favored dealers and privateers.

These factory bikes did sometimes trickle down to the public as they became yesterdays news and no threat to what the factory was trying to accomplish. Check out page 16 of Mike Clay's book on Cafe Racers for a photograph of a Grand Prix Norton registered for road use by Doug Clarke that has alloy wheels and the mag cases with the high front mount etc.

It might not be too hard to find out what well-known rider was racing out of Layton's of Oxford that might have got their sponsorship and factory support, there could not have been many. If you can come up with a name then you might be able to come up with photographs from descendant's of the rider or dealer, or there may even be information in some books.

Walker's book on Manx Norton's mentions that the factory bikes got different con-rods than production jobs. My friend with a 47' Manx did not like the look of the stock rod in his bike so he bought a Carrillo and as he is a toolmaker he made up a whole new crank for his bike and put the original on a shelf. He also did a little work on a Harley Davidson xr750 piston and fit it in and has raced the bike in vintage events for decades. If I had a thirties works bike with questionable old parts I would do the same, put those on the shelf as documentation and for future research, and get the engine together with safe and reliable parts so it could be run without any fear of ruining it.

I would not worry about the bike being a bitza as most race bikes ended up that way after so many rebuilds and blow ups and wrecks. It would be perfectly natural to replace a broken frame with one off a roadster, they wanted to race not restore. As long as you do what would have been done back in the day to keep the bike on the track week after week no wrong can be done. More original bits can be added as the years roll by and you trip over them here and there.

I'm not at all worried about it being a bitsa. As you say, they would have been in the day after a few races.

Where would I look for information on racers out of Laytons? I have never really looked into information like this before! A quick search of the net revealed this: http://www.vintagenorton.com/2011/09/gardners-and-cs1s.html . Looks like a racing CS1 engine made its way to Laytons, could a similar thing have happened with mine?

Regardless of what it is, it is all cleaned up and I am nearly ready to start putting it back together. It looks VERY nice.

Another feature of the works Nortons from 1936 with the high front engine mount is that it was the first year for the plunger rear suspension, which was not available on customer machines until quite a bit later.