ES2 Inter plunger frames

Chris, Do the comments relating to the rear plungers also apply to the pre-war optional spring frames ?

The 1938 brochure lists them as an option for the Inter and shows quite a sharply raked assembly, not fully enclosed by the rear casting (and I have to say, I can't see a brake torque arm).

For 1939, the spring frame as catalogued "...illustrates the spring frame which is now obtainable as an extra on International and E.S.2 models. The mechanism is now totally enclosed..."

Unfortunately, neither the 1938 parts book nor the 1939 supplement give parts numbers for the optional extra frames but from memory there were quite a number of "N. Spring" or "Norton Spring" frames listed as supplied with ES2s during 1939.

Did these 1939 model year ES2s have frames identical to the Inters apart from the front lug...or were Nortons once again being economical with the catalogue illustrations ?

It's not that I need to know, but I find it all fascinating....

Previously david_hooper wrote:

Can anybody tell me the differences between an Inter plunger frame and a ES2 plunger frame. I have been told an Inter engine will not fit into a ES2 frame?? Thanks David

Just a bit to add to the info above. Post war - On the Manx, the front lugs for the tank mount and engine are both cut away at the front for lightness - which is a bit like cutting your toenails to lose weight on a garden-gate frame. I have seen sme Inters with one - the front tank mount(I think) lightened and none on the ES2. Behind the rear down-tube there is a flat strip of metal across the plunger sub-frame that acts as a mount for the rear mudguard and top oil-tank mounts on the Inter/Manx. This is replaced by a tube on the ES2.

Regards,

Ian.

Hi again.

The plungers are the same (post-war) for all models. The plunger 'frame mounts' that carry them have the same casting numbers. I had to fit one to my Manx due to damage it sustained in its past as well as an alloy plunger (right -hand)from the NOC spares scheme (presumably ES2) and they match up in spite of the different angles. There are slight differences in the profile where the frame tube is inserted into the mount. It is tapered to relieve stress on the later post warmodels. My 350 Manx had the earlier non-tapered typeand I had to buildup the replacementwith solder on my 1948 Manx to make it match the other side (see pic).

Regards,

Ian.

hi all

my 1939 es2 has vertical plungers same as my 1951 one

roger

Previously roger_deadman wrote:

hi all

my 1939 es2 has vertical plungers same as my 1951 one

roger

The plungerangle question has oftenintrigued me. I have a48 frame with flat behind theseat post for mudguard, wide front enginemount, footrest lugson thebottomrearrail. and I understandthe head stockbetween top and bottombearingto be adifferentdiameter toanES2 frame. But my Plungerframes are notangled. Thebikehasbeen40 years in storage and was a well used tourer at thetime it was laid up (and of no significant value at thattime). No signsof butchery ormodification but alsonomodelprefix to theframenumber; Whichleads me tobelieve itwas a factory replacement, for a failedor damaged frame.Looking at photos ofpre and post war plunger machines in theKeig collectionseries, themachines with pepper pot plungers andtubular supportswere indeedangled yet I don't see any "framed" ones at theangle. I understandthere were also aluminium plunger"frames" on some of the earlierbikes... Howthey improvedona "rigid" isbeyondme

Last year I had occasion to have both my frames('52 ES2 and '48 Inter) in the shop at the same time and took the opportunity to take a few photos of the 2 together. Have a look.

Mike

Previously Michael Rettie wrote:

Last year I had occasion to have both my frames('52 ES2 and '48 Inter) in the shop at the same time and took the opportunity to take a few photos of the 2 together. Have a look.

Mike

Yesquite differentMike. The blue one(Inter)also hasa lug just behind theright handseat post,whats that for?I see the notch for theright handcasingdrain,do youhavaManxspecmotor? Mine isthe same yearbut I havethe"window" lugs forengineandtankmounts...

Thanksfor this..

Jon

What the heck is that block off in the background?! Sorry off topic!

The mystery motor is a mid '60s Alfa Romeo 6 cyl 2600. Not common to try to squeeze more power from what is generally considered to be a big slug but the owner had the $ and was not shy about spreading it about. Webers, cams, high compression, and tubular headers. Ouch!

Thanks for posting those pictures, Michael. In fact it looks as if the plunger castings are about the only identical part !

It appears that as the camshaft frame is taller at the headstock and the same length forks are used, the effect is to drop the engine cradle and angle the plungers forwards.

The effect is presumably to put engine weight lower and further forward.

Don't forget that the Inter has larger wheels, 20 and 21", versus the ES2's 19 inchers. Not sure which lug Jon is referring to.... maybe the tab for the toolbox. And maybe Dan was referring to the bare block on the floor. I think it's a Maserati 4cyl with a big hole in the side. And here's a shot of a late Manx plunger.

Previously Michael Rettie wrote:

Don't forget that the Inter has larger wheels, 20 and 21", versus the ES2's 19 inchers. Not sure which lug Jon is referring to.... maybe the tab for the toolbox. And maybe Dan was referring to the bare block on the floor. I think it's a Maserati 4cyl with a big hole in the side. And here's a shot of a late Manx plunger.

Thanks Michael,youare right Ican see thetoolboxlug.The "Manx frame" picture is as mine with the"window lugs" on the frontdown tube,kink in thetop tube,flatplaterearguard mount,steeringdamperlug, (hack sawn off inmycase) and the plungers arenear vertical.... The curioustwo hole front seatmountevenfollows...

Whilst you don'trate theAlfa motor,as with all thingsItalian,it sure looksgood! Clearly not ahobbyroom

Best regards

Jon