Frame and Engine identification

Hi Darren,

Your engine has the dimensions of a 596cc single so could be either a Big 4 (sidevalve) or 19S (overhead valve). The S signifying the engine was fitted in a swinging arm frame. The actual engine number should be just in front of the bore and stroke figures (83 x 113). The engine/frame numbers should have a letter and number before the engine and frame numbers e.g.

1954 J154350

J8 is a 1954 Big 4 and J9 would be a 1954 19S in a swinging arm frame

Any photos?

Darren,

The frame number should be stamped on the front petrol tank lug on the near side (left), in line with the front downtube. The engine number should be on the crankcase, to the left of the 82/113, nearer the other nut that holds the crank cases together.

Phil.

Darren,

Number KK 546 is the shop build number and not the frame number. As Philip advises, the frame number is on the LHS under the petrol tank mount. The engine is definitely a Big 4 sidevalve.

Previously ian_richtsteig wrote:

Darren,

Number KK 546 is the shop build number and not the frame number. As Philip advises, the frame number is on the LHS under the petrol tank mount. The engine is definitely a Big 4 sidevalve.

Hello I confirm with this Shop number Not a Fame Number and it's a Big 4 600cc side-valve engine 'Pa' Norton's favourite Motorcycle goodsolidold motorcycle once rebuilt have fun yours anna j

That frame looks as bent as its number. Front end smash by the looks of it. TTFN Jack

It should straighten, they are made from very thick tube!

Darren,

Looks like this frame had a sidecar fitted and is likely to have a cracked frame by the rear, left footrest lug. Look behind the thick metal plate which is bolted onto your frame to see if there is any crack at the bottom of the lug. If you're having the frame straightened it would be prudent to get this repaired at the same time.

Looks like an interesting project, you don't see many Big Fours in a swinging arm frame.

Philip

Previously darren_hutchinson wrote:

Previously john_marshall wrote:

That frame looks as bent as its number. Front end smash by the looks of it. TTFN Jack

Hi

Yes now i've looked at it I can see what you mean, is it to bent to be professionally straightend, or would it be cheaper to find another frame?

It can be straightened, but you may then run into problems with registration with the dodgy framenumber. Not sure the Dating Officer will be able to issue anything for that number. You are also missing the engine number it seems. Probably stolen and crashed a long long time ago. TTFN Jack

The location on the frame top lug is one that I've seen used on WD16Hs for a shop number. The 'matching' engine and frame numbers were clearly applied at the end of the line when everything was fitted and tested.

Do you have a decent high resolution photo of the left hand front fuel tank mounting lug to see if a number has been removed there ? Likewise the engine number location. It may be that the cases were supplied as unstamped spares but then the presence of bore and stroke surprises me as the same cases were used for 500 and 600cc sidevalves.

There is a difference between registering components that have been supplied as new parts and those where numbers have been removed.

Unfortunately, people were not too careful in the past, especially when bikes such as this had reached the bottom of the pile. If an engine went bang then a second hand spare was fitted in order to get to work the next week. Filing the number was easier than taking a day off work and losing a days pay to travel into the county-town to visit the Vehicle Licensing Office in person and have the details changed over.

I think that the curved top tube was normal on the swing arm lugged frames (on the rigids, it applied to some models and periods. I can't make up my mind from the photos if the front downtube is bent.

So what happened to my post with pics of my frame?

I didn't see it, Dan.

This is a pic of my frame

Hello Darren , is this the area in the photo where you have scraped the paint from, the frame number should be there.

Barry

Attachments
frame-numberjpg-jpgf-jpg-1-jpg

K4 makes it a 1955 (model year) ES2 frame.

The Club factory records chap will be able to give you chapter and verse on it.

If you're intending to rebuild it with the non-standard Big 4 engine then it would be worth talking to him first as DVLA are making life quite complicated these days.

On the drop-down menu under 'Records'

...but it says that he's unavailable at the moment.

The side-valve bottom end uses the same basic casting but would require machining skills in order to convert it...and you still have the problem of markings that wouldn't tie in with an ES2.

My impression is that if you build a machine that looks like a 1950s Norton, there is a chance that DVLA will accept it at face value, but as things stand, if it is a custom project with engine and frame that didn't start life together then things may get sticky.

Increasingly there seems to be an official leaning towards the idea that an age-related number should relate to a 'historic' vehicle and not simply a project put together using one or two old parts.

I really would recommend talking to the club Records Officer before deciding what route to follow.