Breather Pipe (similar to that listed in Norton 1948 Spare Parts catalog as Pressure Release Pipe) and 1/4" BSP union nut to fit bevel chamber of all SOHC models (30/40, M30/M40 etc).  This particular pipe is almost identical to the Item 0627, except the pipe extends down a bit further than 0627.  Although this particular pipe is not listed in the 1948 catalog - I have seen original examples more similar to this version than the short (0627) version.  I also think this version is more suitable on the bevel chamber as it extends the pipe down, making fitting a rubber pipe to its end a little easier.

The rest of this listing is the same as 0627:

These pipes are made from good quality copper and then nickel plated to give an excellent satin finish very similar to the original.  The bend shape and ferrule profile are almost identical to originals (please note - obviously these engines were made for many years, and the profiles did change slightly from year to year - but I took this profile from a pipe I believe to be original).

These pipes were listed as fitting the front bevel chamber (some engines did not fit them though - look for a breather union at the rear of the top bevel chamber face - just behind the magneto chain housing) - however, they can also be used on the front crankcase breather in front of the barrel (left of right) if your engine was fitted with a front breather.  

Note: front breather unions are most common on magnesium SOHC racing crankcases, and can be found on either the left/drive crankcase, or timing side/right crankcase - the 350cc pre-war M40 racing crankcase shown in the photo unusually has two breathers!  Therefore, fitting this U-bend breather pipe is useful for attaching a length of black 3/8" bore breather oil pipe (sold seperately - see Item 0634) to re-direct engine oil vapour down to the bottom of bike onto the road.  

Fitting this breather pipe (and black rubber oil pipe if you wish to do so) adds that finishing touch of originality to your motorcycle - I do it with all my bikes.  And obviously - if you are using your Norton in competition events - you will have to fit these pipes feeding into a 'catch tank' to pass scrutineering.

This is a long breather pipe and 1/4" BSP union nut to fit breather union of type fitted to the front of drive side crankcase (i.e. union is on the left side) - most commonly fitted to magnesium M30 (and early pre-Featherbed Manx) crankcases (although can also be fitted to aluminium crankcases if they have similar front breather union fitted - as they sometimes did).

As the Norton Spare Parts Catalog of the 1930's/40's never showed pictures of the magnesium crankcases, it is difficult to confirm for sure if this type of long breather was listed - but I have copied it from a version I have seen on a friends very original 1940's pre-featherbed Manx engine - and I think it looks very period and proper.

In addition, as with other breather pipes we sell - we also supply a seperate 12"/300mm length of stainless steel lockwire,so you can attach 5/8" bore black rubber breather pipe (sold seperately)

These pipes are made from good quality copper and then nickel plated to give an excellent satin finish very similar to the original. 

Fitting this breather pipe (and black rubber oil pipe if you wish to do so) adds that finishing touch of originality to your motorcycle - as well as re-directing your engine mist away from the engine onto the road or a catch-tank

Note: can also be fitted to aluminium International crankcases if they have a breather union in the same place

April 2021: These are currently out of stock we are having a new batch made which should be available in next 3 months - email at sales@racingvincent.co.uk if you wish to reserve

Crankcase feed pipe to cambox and 1/4" BSP union nut's to fit all SOHC models (30/40, M30/M40 etc) - this is the bottom piece of the cambox feed pipe assembly - which we offer here to be purchased seperately - if you require the full assembly see Item No 0629.

In addition, as with other breather pipes we sell - we also supply a seperate 12"/300mm length of stainless steel lockwire, in case your engine has an unusually short height and you want to shorten one of the two copper pipes - and then you will have a piece of lockwire available to wire it up again.

These pipes are made from good quality copper and then nickel plated to give an excellent satin finish very similar to the original.  The bend shape and ferrule profile I have tried to faithfully replicate from an original I have. 

Lockwire:  12"/(approx) 300mm length of Goodrich stainless steel lockwire, for lockwiring breather pipes.

This is a length of good quality lockwire, for wiring up breather pipes (and fuel pipes if required) in a manner that was often done in the 1930's - 50's, particularly on racing bikes.

Best to apply it in the way shown in the second photograph - first run a short length of approximately 2" (50mm) in line with the pipe, bending 90 degrees at the point where you want the lockwire binding to start (i.e. with the tail of the lockwire running out of the end of the rubber pipe).  Then spin the pipe while keeping the lockwire tight with the other hand, creating a number of closely arranged rings around the pipe, and covering the tail of lockwire you had previously laid.  Finally after about 10 turns - bring the wire level with the previously laid tail, cut to the same length and then twist the two tails together - either with lockwire pliers or normal pliers, which should tighten everything up.  Then cut the twisted lockwire approx 0.5"/12mm and bend the twisted element flush to the rings.

Using this lockwire adds a very nice period touch to your restoration - particularly on competition and sports bikes 

Black (original rubber style) 5/16" oil reistent pipe for cambox feedpipe assembly - 4.5"/110mm length.

This high quality oil resistent (and ethanol proof) pipe is the correct length for the cambox feed pipe assembly if you use the type of feed pipe assembly that has a flexible piece in the middle.  All writing from the pipe has been removed

Using this type of oil pipe (rather than the more modern clear pipe) adds a very nice period touch to your restoration - particularly on competition and sports bikes 

Black (original rubber style) 5/16" oil reistent pipe for use for oil breather pipes, oil pipes (or even big bore fuel pipes if required - although 1/4" bore pipe is more normally used) - this listing is for a 3 foot /900mm length

This high quality oil resistent (and ethanol proof) pipe has the correct look and feel to the original black rubber type used on most classic motorcycles in the 1930's - 50's.  This type of pipe was often used on competition bikes.  All writing from the pipe has been removed (a particularly ardous and time consuming task - as all modern pipes are supplied with the makers details along the length of the pipe - which I then have to remove).  

Note: this pipe is high quality 'Codan' pipe (a Denmark manufacturer), hence the price 

Using this type of oil pipe (rather than the more modern clear pipe) adds a very nice period touch to your restoration - particularly on competition and sports bikes 

Black (original rubber style) 5/16" oil reistent pipe for use for oil breather pipes, oil pipes (or even big bore fuel pipes if required - although 1/4" bore pipe is more normally used) - 3 foot /900mm length

This high quality oil resistent pipe has the correct look and feel to the original black rubber type used on most classic motorcycles in the 1930's - 50's.  This type of pipe was often used on competition bikes.  All writing from the pipe has been removed (a particularly ardous and time consuming task - as all modern pipes are supplied with the makers details along the length of the pipe - which I then have to remove).  

Note: this pipe looks exactly the same as Item 0634, except is from an earlier batch, and therefore does not come as certified as Ethanol proof.  It is still rated as oil-resistent and as I sell this pipe as oil and breather pipe, should work just as well for that purpose - and is slightly cheaper than Item 0634

Using this type of oil pipe (rather than the more modern clear pipe) adds a very nice period touch to your restoration - particularly on competition and sports bikes 

This is the E3224 3/8" x 26 tpi BSC engine nut as fitted to many Norton engine bolts.  It has the correct 'reduced head' and greater depth than other commercially available nuts of this thread/size - and is CNC made specially by us for fitting to Norton engine bolts, but in stainless steel 

New Batch Now in Stock - Aug 2023: (price of this stainless bar tripled since last made 3 years ago!  . . our price only risen a small percentage of that)

This (deeper type/Reduced hex) nut was used on numerous SOHC, OHV and SV engine bolt applications (see our other SOHC engine bolts, but it was also used on OHV/SV 3/8" engines - often fitted on both ends of an engine stud), as well as being listed as the nut holding the brake arm on to the brake shoe cam, and also used to secure the 6v horn to the chassis, and the megaphone exhaust megga securing nut on racing models. They are also listed in numerous places on the fittings of Norton Sidecars!  A very useful nut, as they have a deeper depth of thread than other commercially available nuts - so give more strength, hence why used so frequently on Norton models

Bolt Table Legend and Useful Information: 

AF = "Across Flats', i.e the diamter in inches of hex bar between the two opposite flats - this is the diameter the spanner gap needs to be - we use the correct 'British Standard' bar, as fitted to all Norton single cylinder motorcycles originally, to fit BSW spanners. 

UH = 'Under Head' Bolt Length, i.e. when measuring the length of the bolt shaft - dimensions are taken from the distance at the base of the hex head to the end of the threaded shaft.  It does not take into account the height of the hex head, or the slightly rounded chamfer at the end of the threaded shaft, which are additional.  (Please bear in mind length is nominal - there may  be 1 or 2 mm variation because of batch variation). 

Therefore - when comparing the length shown in the table above to your own engine, you need to take into account the width of the engine casting, engine plates and the height of the nut.  Also, any brackets that you may fit under the bolt head - I have tried to base the length of bolts on not having additional brackets unless I know they were standard (the nuts are normally extra width though and can be narrowed slightly if necessary, or one of the washers omitted

Remember that in some cases, bolts were fitted where there may have only been an engine plate on one side - i.e for the rear of the engine on most SOHC engines, the bolt immediately above the magneto platform has an engine plate only on one side, while the bolt under the magneto has an engine plate on both sides - which is why I make 2 versions of these bolts.  Norton did not bother originally, fitting the same length bolt to both)

Reduced Hex Nuts : for many of the bolts and nuts fitted to Norton motorcycles, the AF (Across Flats) diameter was less than normal commerically available nuts for a given bolt shaft size - the rationale for this was that there was not much room around complex castings, therefore you needed to be able to get access with a smaller spanner.  To allow for this, many of the engine bolts and nuts with these 'reduced head size to shaft diameter' nuts also had a deeper depth of hex as well, to provide as much spanner to hex contact as normal bolts - reducing the chance of 'rounding' the hex when applying a lot of pressure with spanners and providing as much thread on the nuts as possible - but important with the pressure required of engine bolts. 

The nuts shown here replicate the Norton nuts and are deeper than commercially available nuts.  In some cases - i.e. if you are fitting thicker washers or ancillary brackets, you may find the nut is deeper than the bolt allows.  In this case the easiest way I have found to reduce the depth of a nut (if a lathe is not available), is to hold the nut in a ring spanner and place its lower unchamfered face carefully against a linisher (make sure you use suitable safety glasses and gloves when doing this) 

Thread Type:  Engine Bolts on Norton engines tended to come in most of the standard British Whitworth diameters, with the following common thread types, where TPI means 'threads per inch':  1/4" (shaft diameter) x 26 tpi (Threads per inch), 5/16" x 26 tpi, 3/8" x 26 tpi, 7/16" x 20 tpi, 1/2" x 20 tpi.

Most thread profiles were originally BSC (British Standard Cycle), but please note that 7/16" x 20tpi is also a UNF standard thread size and none of the tooling manufacturers will now make the BSC profile tooling - therefore we manufacture this size nut/bolt in UNF profile.  These nuts may fit on original bolts, but can be slightly tighter.

Overall, these nuts are high quality, CNC machine finished to look just as the original Norton items, but in non rusting stainless steel, with original Norton dimensions and profiles.   We lightly linish the hex faces on the bolt heads to ensure crisp finishes and we hope you find the will give that finishing touch to any restoration - or just clean up the look of your oily rag, ride to work Norton!

This is the special 13294 (part no listed in 1948 Spare Parts catalog) front engine plate top bolt that is fitted to M30/M40 (pre-Featherbed Manx) magnesium engines.  It has the correct 'reduced' head 0.600" AF hex head, with distinctive Norton curved head finish.  This set comes complete with correct matching E3224 nut and two washers, all in stainless steel.  It is 3/8" shaft diameter  with a 3/8" x 26tpi thread

This particular bolt (as far as I know) was only fitted to Magnesium pre-featherbed racing engines - and is very long!, its shaft length is almost 5 1/4" and overall length is just over 5 1/2" long.  Because of it's length, oringal bolts are very rare to find - most people instead fit threaded studs with nuts both end

We CNC machine this bolt in-house from stainless steel.  As well as having the correct 'reduced head' 0.600" AF hex that was originally used on these bolts, the head shape profile is just as it should be with distinctive shallow dome.  It is also fitted with the correct 'deep' E3224 engine bolt nut (sold seperately as item 0667), which allows extra spanner purchase to be applied with less risk of stripping threads than with shallower commercially available nuts.

Sorry this bolt is not cheap - but it's length and head profile means it is a complex and time consuming bolt to make - even on a CNC machine, requiring 4 seperate operations

See this bolt being made on Youtube: https://youtu.be/PHriTiDE5Uc

This is the E3238 7/16" x 20 tpi engine nut as fitted to many Norton engine bolts.  It has the correct 'reduced head' and greater depth than other commercially available nuts of this thread/size - and is CNC made specially by us for fitting to Norton engine bolts, but in stainless steel.

Note: the thread for this nut is 7/16" x 20tpi UNF profile.  This is almost identical to the original 7/16" x 20tpi BSC thread, but with a fractionally different tooth profile.  I recommend if using these nuts with original bolts you buy one nut and try first.  If bought with our corresponding bolts they are a matching pair.  Unfortunately original BSC taps in this size are no longer available.

Bolt Table Legend and Useful Information: 

AF = "Across Flats', i.e the diamter in inches of hex bar between the two opposite flats - this is the diameter the spanner gap needs to be - we use the correct 'British Standard' bar, as fitted to all Norton single cylinder motorcycles originally, to fit BSW spanners. 

UH = 'Under Head' Bolt Length, i.e. when measuring the length of the bolt shaft - dimensions are taken from the distance at the base of the hex head to the end of the threaded shaft.  It does not take into account the height of the hex head, or the slightly rounded chamfer at the end of the threaded shaft, which are additional.  (Please bear in mind length is nominal - there may  be 1 or 2 mm variation because of batch variation). 

Therefore - when comparing the length shown in the table above to your own engine, you need to take into account the width of the engine casting, engine plates and the height of the nut.  Also, any brackets that you may fit under the bolt head - I have tried to base the length of bolts on not having additional brackets unless I know they were standard (the nuts are normally extra width though and can be narrowed slightly if necessary, or one of the washers omitted

Remember that in some cases, bolts were fitted where there may have only been an engine plate on one side - i.e for the rear of the engine on most SOHC engines, the bolt immediately above the magneto platform has an engine plate only on one side, while the bolt under the magneto has an engine plate on both sides - which is why I make 2 versions of these bolts.  Norton did not bother originally, fitting the same length bolt to both)

Reduced Hex Nuts : for many of the bolts and nuts fitted to Norton motorcycles, the AF (Across Flats) diameter was less than normal commerically available nuts for a given bolt shaft size - the rationale for this was that there was not much room around complex castings, therefore you needed to be able to get access with a smaller spanner.  To allow for this, many of the engine bolts and nuts with these 'reduced head size to shaft diameter' nuts also had a deeper depth of hex as well, to provide as much spanner to hex contact as normal bolts - reducing the chance of 'rounding' the hex when applying a lot of pressure with spanners and providing as much thread on the nuts as possible - but important with the pressure required of engine bolts. 

The nuts shown here replicate the Norton nuts and are deeper than commercially available nuts.  In some cases - i.e. if you are fitting thicker washers or ancillary brackets, you may find the nut is deeper than the bolt allows.  In this case the easiest way I have found to reduce the depth of a nut (if a lathe is not available), is to hold the nut in a ring spanner and place its lower unchamfered face carefully against a linisher (make sure you use suitable safety glasses and gloves when doing this) 

Thread Type:  Engine Bolts on Norton engines tended to come in most of the standard British Whitworth diameters, with the following common thread types, where TPI means 'threads per inch':  1/4" (shaft diameter) x 26 tpi (Threads per inch), 5/16" x 26 tpi, 3/8" x 26 tpi, 7/16" x 20 tpi, 1/2" x 20 tpi.

Most thread profiles were originally BSC (British Standard Cycle), but please note that 7/16" x 20tpi is also a UNF standard thread size and none of the tooling manufacturers will now make the BSC profile tooling - therefore we manufacture this size nut/bolt in UNF profile.  These nuts may fit on original bolts, but can be slightly tighter.

Overall, these nuts are high quality, CNC machine finished to look just as the original Norton items, but in non rusting stainless steel, with original Norton dimensions and profiles.   We linish the hex faces on the bolt heads to ensure crisp finishes and we hope you find the will give that finishing touch to any restoration - or just clean up the look of your oily rag, ride to work Norton!