These are the distinctive 9/32" x 26tpi BSC tapered locknuts as fitted to the Norton OHV Ball type rocker adjusters from approximately 1926-29.  These have been CNC manufactured in stainless steel to exactly the same dimensions as a Norton 1920's example.  Note we also sell the locknut with the actual adjuster - see Item 1119, but as the original nuts are often chewed or come loose and fall off - we sell them on their own here.  

Price is each (i.e. one locknut)

The thread on these locknuts is - 9/32" x 26tpi BSC thread - as per the original item.

This nut is CNC manufactured in stainless steel to the original Norton design - which has a slight taper on one end - which should fit into the original Norton OHV Rocker recess.  The other end has a minimum chamfer.  This locknut is copied from an original period Item - but unlike the original, ours are CNC manufactured from stainless steel - to prevent rusting.  It should be noted that on the original 1920's nut that we coped - we noted that the depth of this nut was fractionally shallower than the original 1930 onwards original nut we also manufacture (Item 1123) - but the difference is minimal, and I suspect either type could be used.

See also the description listing for Item 1119 (Ball Type Adjuster and Locknut - Pair) for more background information on these items.

If these nuts are showing out of stock - then Item 1123 is a possible alternative as the depth difference of the later nut is only fractionally deeper than this type - we decided to make both types because we wanted each Rocker Adjuster/Locknut combination to be true to the original patterns we copied

This Flat Bottomed Rocker Adjuster and Tapered Locknut are to fit the first SOHC Walter Moore (i.e. Cricket Bat type) and 1930 - 1937 OHV Models.  They were fitted to CS1 models from 1927-1930 (approximately) and OHV models from 1929 - 1937.  This type of rocker adjuster were fitted to the rear rocker arms and acted directly on the valves.  We have CNC manufactured this type using an original early 1930's Norton item as the pattern and includes the correct profile locknut, with tapered bottom face, the locknut being in stainless steel. 

Price is for a single adjuster and locknut (i.e. 2 parts)

We have CNC manufactured this type of rocker adjuster using an original early 1930's Norton item as the pattern - and replicating all dimensions as per the original.  They are made from case hardened EN32B, but like the Norton originals - the threads are 'painted off' before hardening, so the threads do not go brittle in the hardening process.  The reverse end of the adjuster has a square head milled into it, for adjusting tappet clearance iwth a small spanner - again replicating the dimensions of the original Norton square.  It should be noted that the thread of this type Rocker Adjusters (and the slightly earlier  ball type adjusters we also offer - Item 1119) is actually 9/32" x 26tpi BSC thread - as per the original item.

As well as the actual hardened adjuster, we also include the correct profile locknut - which has a slight taper on one end - which should fit into the original Norton OHV Rocker recess.  The other end has a minimum chamfer.  This locknut is copied from an original period Item - but unlike the original, ours are CNC manufactured from stainless steel - to prevent rusting.  It should be noted that on the original 1930's nut that we copied (which was still fitted to a flat bottomed adjuster) - we noted that the depth of this nut was fractionally deeper than the original 1920's nut fitted to the earlier 'Ball type' rocker adjuster (Item 1119) - but the difference is minimal, and I suspect either type could be used for either application.

Each Rocker Adjuster and Locknut is supplied assembled with high melting point grease applied - to prevent corrosion in storage.

Price is for a single adjuster and locknut (i.e. 2 parts) - Therefore 2 of these are required per engine.

Backgound: 

This flat bottomed rocker adjuster is of the type that looks to have been fitted to most OHV models and also early SOHC models from approximately 1927 (in the case of Walter Moore CS1 Models) through to 1937 OHV motors.

This specific design - which has a flat foot, slightly wider than the thread shaft, is pictured in the 1933-34 Norton Spare Parts Catalog - and given the Norton part number 9163 - and was shown there as an adjuster and locknut, as we offer here - i.e. 2 parts.

As well as having this flat foot, the other distinguishing feature of this type of adjuster s that the thread is 9/32" x 26tpi BSC.  And finally, the other feature is having a 'square' top at the other end of the adjuster - to allow tappet clearance to be adjusted, once the tapered locknut is looesened.

The reason these features are important - is that there does seem to have been some variations on this adjuster offered - particularly on earlier Walter Moore CS1 and OHV models in the late 1920's - for example, I have also seen early examples that look to have a pad which is closer to the diameter of the shaft, and other examples that have a Hex pad, rather than a round pad - Which I assume was to make adjustment possible from the lower end.

Therefore please satisfy yourself before ordering that your model of Norton has the correct 9/32" x 26 tpi thread in the rocker - and that you are comfortable to use this design with the wider flat pad - which seems to have been standardised on all OHV models by 1933 at the latest.

Wtih regard to the use of this type of Rocker Adjuster on SOHC Engines:  It is difficult to be distinct about Walter Moore CS1 development between 1927-30 (and I am definitely not an expert on this model) - but they were definitely fitted with the 9/32" x 26 tpi adjuster - although early examples may have had a slimmer hardened head than the type shown here -this type should be interchangeable, but please satisfy yourself before ordering us, or email us on sales@racingvincent.co.uk before ordering.

Having consulted with some early SOHC experts- I gather that occasionally worn CS1 rocker arms were drilled out to a larger thread to take later 5/16" SOHC Adjusters (see our SOHC Cambox section for standard 3 part SOHC tappet adjuster sets) - but before ordering these adjusters - please satisfy yourself that your CS1 (Walter Moore) rocker arms still have a 9/32" thread.

Likewise - the earliest Arthur Carroll SOHC cambox's - i.e. 1931-33 era also had differnces to later SOHC cambox's.  I cannot be certain, as I do not have a complete earliest type Arthur Carroll cambox in my collection - but there is also a good indication that the early versions of this type of cambox may also have used this type of adjuster (early Arthur Carroll Camboxs are often identified by a more curved front bevel cover casting thant the standard later version).

With all of this background - the key thing to remember is:  It is very difficult to be definitive about types and sizes, as so few engines are totally original  . .. and a high mieage engine may have had its consumable parts replaced many times over the years - often using whatever parts are available at the time.

However, with all these 1930's engines - up to the introduction of the adjustable pushrod on 1938 onwards OHV engines - these 9/32" rocker pads are manufactured to an original and well tested Norton design - hence why it is important to note that the thread diameter is the most important point to note if you have a Norton single model from late '20's to 1937 where the tappet adjuster sits directly over the valve stem.

You can email us on sales@racingvincent.co.uk if you need more information or need to check 

This Flat Bottomed Rocker Adjuster and Tapered Locknut are a slightly longer version of the 9163 (Std length) adjuster fitted to early SOHC engines and most OHV models up to 1937.  We modellecd this 5mm longer version on an original adjuster - that may have been modified, as at least one customer has requested a longer type. 

Price is for a single adjuster and locknut (i.e. 2 parts)

At the same time as manufacturing the 'standard length' 9163 - Our Item 1121, one customer that had been helping us with original patterns had requested a longer type of adjuster, to fit his early 1930's OHV engine - which had a longer original adjuster fitted, see accompanyning photo.  As you can see, this adjuster had a longer head than the more common version.  Although there is a small chance this was original Norton - it is probable it is actually an original standard version that had had its head built up later in life.  Regardless - for whatever reason, the engine this adjuster came from required a longer adjuster than the normal 9163 type, to give the correct tappet adjustment.

Therefore, we have made a small batch of this longer version of the 9163 type adjuster, in case other customers also require a longer version.  As you will see, for our longer versions - we have replicated the original 9163 design - but the length of the thread on this longer version is 5mm longer than standard.  Othen than that, all dimensions are as per our item 1121 (Std 9163 type) - so before purchasing this type - also read the background information for that item as well.

The locknut supplied with this adjuster is the same stainless steel tapered locknut as the standard 9163 adjuster.

Thread for this adjuster is also the same as the standard version - 9/32" x 26tpii BSC

Final note October 2022: we have only made a small batch of these longer versions - as we are not sure what demand there will be for them, so please bear this in mind - stocks of this type are limited

Email us on sales@racingvincent.co.uk if you require more information on this item, and please also read the full description against Item 1121 as well.

These are the distinctive 9/32" x 26tpi BSC tapered locknuts as fitted to the Norton OHV/Walter Moore CS1 Flat Pad type rocker adjusters (our items 1121 and 1122 from approximately 1929-37.  These have been CNC manufactured in stainless steel to exactly the same dimensions as a Norton 1930's example.  Note we also sell the locknut with the actual adjuster - see Item 1121 and 1122, but as the original nuts are often chewed or come loose and fall off - we sell them on their own here.  

Price is each (i.e. one locknut)

The thread on these locknuts is - 9/32" x 26tpi BSC thread - as per the original item.

This nut is CNC manufactured in stainless steel to the original Norton design - which has a slight taper on one end - which should fit into the original Norton OHV Rocker recess.  The other end has a minimum chamfer.  This locknut is copied from an original period Item - but unlike the original, ours are CNC manufactured from stainless steel - to prevent rusting.  It should be noted that on the original 1930's nut that we coped - we noted that the depth of this nut was fractionally deeper than the original earlier 1920s ball type rocker version of the same nut.  The difference is minimal though, and I suspect either type could be used if one or other type is out of stock.  

See also the description listing for Item 1119 (Ball Type Adjuster and Locknut - Pair) for more background information on these items.

If these nuts are showing out of stock - then Item 1120 is a possible alternative as the depth difference of the later nut is only fractionally shallower than this type - we decided to make both types because we wanted each Rocker Adjuster/Locknut combination to be true to the original patterns we copied

These Cylinder Head studs are of the type fitted to pre-war OHV Valve engines in the late 1920's and early 1930's, where the design of OHV engine had seperate head studs (i.e. before the introduction of long 'through' studs. See listing for more information.  Price is per stud

Price is per stud.  Normally 4 are required per OHV Cylinder Head.

We have CNC machined these from stainless steel, using an original 1932 OHV Cylinder Head stud as the pattern - which can be seen in one of the accompanyning photos - alongside an original, but very chewed cylinder head sleeve bolt (not included).   WD16H cylinder head stud to ensure we got the lengths of thread going into the barrel, and protruding from the cylinder head, as per the original Norton stud.

It is difficult to be definitive about which OHV models used this exact size stud, but a similar cylinder head stud is shown for OHV models from the 1929 Spare Parts Catalog (part number 4067), the 1931-32 Spare Parts Catalog (3X71) and 1934 Spare Parts Catalog (part number 9135).  This stud was copied from a 1932 OHV Model 18 engine, in the middle of this range. 

Email us on sales@racingvincent.co.uk if you require more information to confirm these are correct for your engine.

Note October 2022:  Sorry, but at this time we cannot offer the sleeve type cylinder head nuts shown in one of the photographs, but email us if you are interested - we are considering making a batch (recent increases in price of stainless steel and machining means these would not be cheap though!)

This distinctively styled Cylinder Base Nut was of the design fitted to OHV singles, before the OHV design switched to 'Through Type' long cylinder studs in approximately 1935. They were also used on Side Valve engines - both types employing a coarse Whitworth cylinder stud thread. 

Price is per stud.  Normally 4 are required per OHV or SV engine.

Background and Model Fitment:

We have CNC machined these nuts from stainless steel, using an original 1931/32 OHV Base Cylinder Stud Nut as the pattern - which can be seen in one of the accompanyning photos.  They have a coarse 3/8" BSW thread, a deep hex (ideal for getting a good ring spanner on), a wasted shoulder where it secures to the barrel base flange, and a distinctive shallow curve to the head, as many Norton nuts do.  Being of stainless steel - as well as not rusting, they greatly improve the appearance in the prominent barrel area.

It is difficult to be definitive about which models used this exact pattern nut - but a picture of it showing in the 1934 Norton Spare Parts Catalog is shown in the accompanying pictures - where it is described as Part Number 9003, and shown as being fitted to Models 1, 16H (side valve), 18, 19, 20 and ES2 (OHV engines) for that year.  In the later 1937 Norton Spare Parts Catalog (by which time the OHV engines were using full cylinder/head studs), Part Number 9003 is still being listed - but by this time indicating it was only being fitted to Side Valve engines, as you would expect.  Again, the 9003 nut appears again in the 1939 Spare Parts list, showing it was still being fitted to Side Valve models of the 1938-47 design.

For Post 1948 Sidevalve engines, it is difficult to be clear if the same shouldered nut was still being fitted - as the picture shown in postwar Spare Parts Catalog is unclear, and the part naming system changed - however, the same 3/8" BSW Whit crankcase studs were still being fitted, so will let you decide if you wish to use these on a Post 48 sidevalve engine. 

Late 1920's OHV and Walter Moore CS1 engines:  A similar nut - Part Number 4069 is described as being fitted to the ES2 Model in 1929 - but it is difficult to tell if it is identical.  The important dimension for this nut is that it has a 3/8" BSW Coarse thread (unlike most cylinder nuts, which used fine threads) - therefore if you have an early OHV engine using this thread - then this should fit.

Finally, it should be pointed out that the Walter Moore CS1 engine also used a similar Cylinder Base Stud.  Some catalogs of that era show a different nut being fitted to the CS1 engine, but it is difficult to be definitive.  However, if you have 3/8" BSW studs protruding from the crankcase, then again these should fit.

Email us on sales@racingvincent.co.uk if you require more information to confirm these are correct for your engine.

This item listing is for a complete Norton OHV non-adjustable pushrod, of the type that was most commonly fitted to Norton OHV models between approximately 1930 and 1937. 

Price is Per Pushrod

Please State Length/Type Required when placing order (in 'Comment' box, when completing order in Checkout section):

Currently we have two 'Standard' lengths kept in stock - but there seem to have been slight variations in length by year - even for 350cc and 500cc capacities - so we can also make these up to your requirement as required.  If ordering either of the two 'standard lengths' below - please confirm these are the correct length for your engine before placing order:

- 350cc Length:  Overall Length (end to end) - 12.430" +/- 0.030" tolerance: (original Norton pushrod shown in photo, alongside our identical version)

- 500cc Length:  Overall Length (end to end) - 12.750" +/- 0.030" tolerance

- Other 350cc, 500cc, 600cc or Non-Std Length Pushrod Assemblies - TO ORDER:

Talking to customers - it seems most likely that in the 8 years that OHV models were fitted with this type of pushrod there may have been variations in both 350cc and 500cc engines, as well as 600cc Model 19 length.   Therefore we recommend you measure the length you require, and if the two length offered above are not suitable, we can make up a pushrod to your required length.

PLEASE NOTE:  Unfortunately we cannot accept Returns on a pushrod made to your custom length - so please ensure you are absolutely sure you have specified the correct length when you order the pushrod - and expect us to email you before we commence assembly of the pushrod, to make sure the dimension you have providied us with is correct.

 Expect pushrods in custom lengths to take 2 - 3 weeks to make up, and we will email you to confirm the dimensions you have provided

Background and Manufacture:

The individual parts for these pushrods faithfully replicate those of the original Norton design - with both the top and bottom tappet pieces being machined to exactly the same dimensions as original items, from case hardened EN32B. 

The tube itself is made from the same gauge of seamless cold drawn steel as original tubes, with the ends pressed on, as per original items. 

When fitting these pushrods, adjust tappet adjustment to the correct tolerance - but then check adjustment again after approximately 50 miles use - as just like the original pushrods, they may 'settl'e in initially,  (Rememnbering - that with this design, as per the original Norton items, the ends are pressed onto the tube with the same interference fit as originals - but excess force cannot be used when assembling without risk of bending the long pushrod, hence why they may 'settle' by a few thou when first used).

This non-adjustable type of pushrod looks to have been fitted in various lengths on most models from 1929/30, through to the end of 1937.  For this type of OHV engine, the tappet adjustment was made by tappet adjusters screwed directly into the rocker arms - we can also supply those adjusters (see Items 1121/1122/1123) - therefore this pushrod type did not have any provision for adjustment itself.  In 1938 the OHV was redesigned, and a similar pushrod with adjustment at the top was introduced - we also sell this pushrod type - Item 1125

Price is for one pushrod - normally we will supply these assembled - but if necessary, we will sell the components so that you can make a pushrod up to your own length, at some point in the future.

Finally - it is difficult to be definitive on what year this type of pushrod was first used - we have said circa 1930 - but they may have been fitted from 1929 (i.e. - when first manufctured without provision for a lower pushrod Return Spring).  Before this design, the early OHV engines had a similar pushrod design - but the bottom tappet piece had more than one design type, as they usually also held a pushrod return spring in place.  Sorry, we do not offer those earlier types - but will consider supplying tubing and top pieces seperately if you wish to make your own earlier pushrod.  

Note: Similar pushrods were also fitted circa pre-1930, but with different (lipped) bottom pieces - to allow for a pushrod Return Spring. Sorry, we do not manufacture this earlier type - but we would be interested to purchase or borrow an original pushrod of this type - as a pattern, and would consider making it in the future.

Price is per pushrod assembly (i.e. 2 required per engine)

This item is for a complete (single) adjustable pushrod assembly to fit the 1938-47 design of OHV Engines.  This design employed the earlier 1930's long steel pushrod tube design - but unlike the earlier design, the top piece had a screw on adjustable top cup and locknut. We keep the most common 500cc length in stock, but can also supply these to order - to your length. All parts are CNC manufactured to the original dimensions, including tolerances for press fitting the pushrod ends to the tube.

Price is per pushrod assembly - 2 pushrods are required per engine.

When fitting, adjust tappet clearance as you would normally - but then re-check tappet clearances after approx 50 miles - as pushrod ends may 'settle' a few thou.  The pushrod ends are pressed on with same interference fit as original items - but just like those engines would have been run-in in period - this type of pushrod design means they may 'settle' slightly in use.

UPDATE OCT 2022:  These are now available in what we believe are the most common '500cc' length, 'off the shelf'.  The length of this pushrod has been copied exactlly from an original 1939 500cc pushrod - as shown in the accompanying photos - it has the following dimensions:

500cc Standard Length Pushrod Assembly: (to the best of our knowledge - please contact us if you have a 500cc engine of a different length):

- Overall length of pushrod, with top threaded 'cup' adjuster removed: 12.540" - 12.550"

- Overall Length Range of pushrod with top threaded 'cup' adjuster fitted:  12.950" - 13.230" (+/- 30 thou tolerance)

350cc, 600cc or Non-Std Length Pushrod Assemblies:

However, we can also provide this pushrod assembly to your custom length - i.e. 350cc (Model 50) or 600cc (Model 19).  To make them to your length, we require the overall length of the pushrod - but without the top 'cup' adjuster fitted (see picture of the pushrods between a large caliper to see what we mean).  We would normally expect to be able to supply a pushrod to your required length within 2 - 3 weeks of you placing an online order.

PLEASE NOTE:  Unfortunately we cannot accept Returns on a pushrod made to your custom length - so please ensure you are absolutely sure you have specified the correct length when you order the pushrod - and expect us to email you before we commence assembly of the pushrod, to make sure the dimension you have providied us with is correct.

What Do I Do If I Dont Already Have a Pushrod To Measure Against???:

If you are building an engine afresh, and dont have any pushrods for that engine - then follow these instructions to measure the length of pushrod required:

- First, loosely assemble the main engine components - including the crankcases with cams and cam followers fitted, barrel, head, rocker box.

- Ensure head has valves fitted and that the rocker box is tightened down with alloy rocker box spacers in place and that the rockers are touching the top of the valves

- Ensure the cam followers are sitting on top of the cams, with the cam base profile touching the follower (i.e. the follower must not be in the cam lobe 'lifted' position)

now use welding wire or rod (or some other similar tool to measure) to measure the distance between the lowest part of the 'cup' in the cam follower, and lowest point of the spherical ball of rocker arm.  We will use this distance to calculate a pushrod which has 'mid adjustment' at this length.

Background For This Design:

These pushrods were particular to the 1938-47 OHV engine - this being the first type to employ the adjuster as part of the pushrod.  Prior to the 1938 design, a similar long/slim pushrod was also fitted - but the tappet adjustment for the earlier design of engine was done with rocker adjusters screwed into the rockers, therefore the pushrod was a fixed length.  We can also supply that (non-adjustable) type of pushrod - Item 1124.

This type of pushrod was only fitted until 1947.  In 1948 the OHV engine received a complete re-design and long cam pushers were fitted into the timing case, with much shorter/thicker alloy pushrods fitted, which were less inclined to flex.

Therefore this type of 1938-47 pushrods were only fitted for a relatively short period and are now extremely difficult to find at autojumbles.  Added to that, it is not unusual for the threaded adjuster at the top to strip its thread (or the locknut to strip its thread).  We can supply locknuts seperately (Item 1126), but if you have a pushrod with a stripped thread on the top adjuster - we can only recommend replacing that pushrod - it is very difficult to remove the threaded top piece from an original pushrod without damaging the tube - as they were originally pressed on with an interference fit and are very difficult to remove.

We manufacture the bottom 'Male' ball end and the top female 'cup' threaded end from Case Hardened EN32B.  The tubing is cold drawn seamless steel of the same dimensions and wall thickness as the original tubing.  The top tube threaded adjuster and locknut are both CNC machined from stainless steel.  The two pushrods ends are pressed on with the same interference fit as original Norton items.

This type of pushrod are now extremely difficult to find - and it is not unusual to find the thread on originals has stripped, and therefore not possible to adjust and lock them.  The other common fault - particularly if the engine has been left unused  for a period of time, is top ball cup or bottom ball corrode and lose their case hardening.  These pushrods have been manufactured to the original design, using original Norton pushrod assemblies for the patterns.

Email us on sales@racingvincent.co.uk. if you require more information before placing order - or state length required when you do place an online order. If no additional details are supplied - we will assume you require a 'std 500cc' length item of the dimensions provided at the top of the listing.

Final Note:  we supply each pushrod assembled using high temperature grease, and both cup and ball ends smeared with grease, to protect against corrosion in storage.

Price is per pushrod assembly (i.e. 2 required per engine)

This item 'Pre-Listing' is to let Pre-war OHV owners know - we will shortly be manufacturing batch's of the distinctive and long Norton OHV Pushrod tubes - in seamless stainless steel, and the special bottom Hex Gland Nuts that were fitted to each respective type. 

This update written July 2023 - with a view to producing both types to be available late 2023.

We intend to be making two Pushrod Tube Assembly types:

- The earlier 1930-37 type OHV pushrod tube (0.750" Tube OD).  The tube length shown was standard for both 500 and 350 models.  By special request we may also make the 600 length - email us now to order that length.

- The tapered Hex bottom nut that slid over this type tube

- We will also consider making the special two thread ended ferrule that screwed into the crankcase, and the pushrod nut then attached to.  We are only likely to make a few of these -unless pre-ordered by customers - but if yours has a hex that is rusty or badly chewed . . . you might want to contact us now to let us know your interest

- The later 1938-47 Type OHV Pushrod tube (0.875" Tube OD):  We will be making the 500cc length showin in photo, but email us if you 600cc/350cc requirement

-  Again, we will also be manufacutring the special threaded nut that screwed into the crankcase.  

For all items - they will be manufactured from stainless steel - for the tubes this will be best quality 'seamless' stainless steel, and for the nuts, they will be CNC billet turned from the correct Imperial Hex size stainless bar, and BSC threads.

For the pushrod tubes, to avoid distortion of the tubes, rather than pressing the lip at the bottom of the tubes (they were very long on the pre-war Nortons - swaging the end over would be difficult on stainless tubing) - we will silver solder in a machined 'lip' at the bottom of the tube - as Norton did themselves on some later pushrod tubes.

Email us on sales@racingvincent.co.uk if you require more details, or wish to reserve any of these items.  Once price is confirmed, we may ask for a small deposit to secure them

This item is for a spare locknut to fit 1938-37 OHV Pushrods.  These are CNC machined fron stainless steel to the same dimensions as original Norton pushrod locknuts, an original nut being used as the pattern, however we manufacture these in stainless steel.  We also sell the complete pushrod assembly - see Item 1125, but as stripped locknuts was a common issue with this pushrod design, we also sell the locknut seperately. 

We CNC manufacture these nuts from stainless steel using the correct Imperial Whitworth hex size, so they use the same 1/4" Whit spanner as the original nuts and the ball end hex.

Price is each

If you look carefully at the locknut, you will see it has a smaller chamfer on one side - that side is intended to lock against the end adjuster, although it does not make a lot of difference . . . but that is how the original nuts I have seen have been, 

In practice - as original pushrods for this engine type are now @80 years old, it is common to find the locknut has stripped its thread, therefore these nuts are useful if you have that issue.  However - I have also seen pushrods where the main adjuster thread (i.e. the male thread hex end, that presses onto the pushrod tube) has also stripped - if this is the case, then sorry - but you will need to replace the entire pushrod (our Item 1125), as we do not sell those items seperately.  I can also tell you that removing the original threaded end from an original pushrod is very difficult - as they are pressed on, and this can easily damage the tube to remove them.

Update Aug 2023:  I was asked by a customer recently if this locknut will fit the later 1948 onwards pushrods? (see last picture for this listing) - yes they will.  All key dimensions are the same - thread/hex/depth etc.  Actually, original 1948 onwards nuts dispensed with the chamfer (I doubt this was laziness on Norton's part - I think they probably found not many customers used proper pushrod adjuster spanners - which are slimmer than normal open ended spanners, and a nut without chamfer lessened chances of them getting mauled.  FYI - the last picture with locknut fitted (in lower right corner) shows a genuine slim pushrod nut spanner - of slim type . . . always a good idea if you can use them, these have been with me for 40 years! . . . but in answer to the question - yes these nuts will fit 1948 onwards OHV pushrods!