I am now able to offer a selection of lasercut engine plates to fit both International and SOHC Manx models in both 350cc and 500cc variants. In most cases these plates are replicated from originals and have been trial fitted to frames. It is important to point out however that even with genuine Norton engine plates, it is rare to find two sets of plates exactly the same!, they often had small variations. Because of this, for the most common types I can offer them fully drilled or semi drilled, where the final frame hole is left blank, so you can drill it to fit your own frame and be sure it is correct. If you are not sure which set to buy, I am prepared to offer to send both types, and then if the fully drilled set does fit, you just send back the other set or vica versa. Obviously, while offering this service I do expect you to pay for extra postage to send the unwanted set back to me! I am also increasing the range all the time to include new brackets and fabricated parts, like the oil tank brackets fitted to both Manx wrapround tanks and International half wrapround tanks. In nearly all cases, these parts are modern lasercut and are copied from originals using special scanning software and then replicated using Autocad drawings

This item is for a full set of relacement springs to fit the Norton 'Gardengate' (1938-54) Plunger frame rear plunger units. 

They are UK manufactured for us by a specialist spring manufacturer who has been involved in the making of springs for historic makes for many years and are excellent quality.  A set of genuine original Norton plungers springs were used as the template - and ours match the gauge and poundage of these originals.

In the accompanying photographs is a picture of the type of frame these springs fit - this being known as the 'Gardengate' frame which was introduced in late 1938, and was used for various Norton models, through until (approximately) 1954.  This type of frame should not be confused with the earlier (and much less common) 'Big Plunger' frame which was only produced for some SOHC/ES2 models in 1937/38 - if you have one of these types of frame, sorry - that frame uses very different springs to these.  The frame in the photograph is a 1948/49 Manx frame - and was used to supply the original springs (as I knew they were original  - probably not stripped for 50 years, but also would have had very little use), however, the same springs were fitted to all Norton models using this type of frame.

The set of 4 springs  - consists of two thicker 'Compression' springs (these fit above the alloy sliders) and two slimmer 'Rebound' springs (that fit below the alloy sliders).  Needless to say, you should be extremely careful when stripping old springs and fitting new ones - always wear eye protection and be aware that the springs can fly out, as can the covers.  

I have removed many plunger units in the past - and often found that the original plunger springs are badly worn and tired (particularly on a well used road bike) - or sometimes even fitted with non original springs.  If your springs are tired or worn then replacing them with a set of these springs should return your bikes rear suspension to the original Norton fresh specification

Final point - I may be having the rear plunger covers manufactured shortly - if possible using stainless steel for the polished covers.  If you are interested in a set of these - email us at sales@racingvincent.co.uk, it may be useful to gauge the demand for these items 

This item is for a full set of Gardengate Plunger springs covers, UK manufacured in stainless steel.  The four covers that would have originally have been chromed come polished.  See detail listing for more information

These items have been UK manufactured by a specialist who also makes similar covers for other one make clubs.  They are spun and then TIG welded from stainless steel and are made to a very high quality.

When they come to us, we then remove the welding seam (but this should be pointed inwards, when fitting, so no trace of the seam weld is visible) and then the 4 covers that would originally have been chromed steel are polished on stainless polishing mops to a similar finish to the original chrome items. The other 4 covers (which originally would have been painted gloss black) are supplied unpolished, ready for painting.  All 8 covers are supplied individually wrapped in paper to prevent any scratches in storage.

These covers are identical in form to the original Norton covers, except, being manufactured from stainless steel, they are harder wearing than the original mild steel covers and will not rust.

The accompanyning photographs show the plunger covers fitted to an original Norton plunger casting - and they are sided as the originals so they fit nicely over the conical alloy casting in the middle part, or the steel shaft at the outermost ends.

These are not the cheapest of covers, but being spun (and welded) stainless steel, are expensive to manufacture.  However they are nicely made - and as the original Norton covers (as shown on the left side in the last photograph) wear badly - and have often corroded through, or just worn away on one side, these are an excellent replacement that will last for many years.  Note, I only have limited sets of these covers available

We also sell replacement springs for these Gardengate Norton plunger frames - again, original Norton springs being used as  patterns and UK manufactured by specialist spring manufacturers - Item 0829 - therefore as both original springs and covers tend to wear badly, these two items together offer a complete replacement. 

I have held one set of these back for myself and will fit them to my own 1939 Gardengate Manx Norton, which is shown in the photograph.  When I have painted them and come to fit them, I will take photographs and add to this listing.  E-mail us at sales@racingvincent.co.uk if you require information on how to remove and refit springs/covers in Gardengate frames.

Update Nov 2022:  We sold out of these in April this year, we are now having a new (small) batch manufactured.  Please email quickly on sales@racingvincent.co.uk if you wish to reserrve a set, quoting this Item reference - as we are trying to confirm the number to have made (the material is very expensive with current price increases). Price showing is still the previous price - expect this to rise by at least 10% - but if you do wish to pre-order we will confirm final price up front, and ask for a £50 deposit to secure.  Thx.  

This listing is for a complete headrace bearing set, to fit those Norton models fitted with Norton girder forks - from approximately 1931 to those still being supplied with girder forks in 1946.

The set consists of 4 hardened headrace bearings and two sets of ball bearings. Original Norton girder fork headraces were used as the pattern for manufacturing these and all dimensions are the same.

Three of the races are identical and have a grease track and a small hole in the track, to allow for greasing from the frame and top crown grease nipples. This type are fitted to both sides of the top race (girder fork top crown and upper frame race), as well as the bottom race frame race.

The fourth race does not have a small hole, and this race is intended to be fitted to the base of the girder fork steering stem, as shown in one of the photographs (this is specific to the girder fork models - if you have a telescopic fork model see listing 0913). This race also has its inner face ground to the exact dimensions of original races.

As shown in the photographs bearing races are supplied with the ball race area smeared in Castrol moly grease to protect them from rusting in storage.  I find this is also a good grease to use for headraces on assembly (note in some photographs 2 bags of balls are shown - but there is one bag supplied with enough balls for two races + 1 additional ball in case you lose one on assembly)

Fitting Tips:

- To fit these races - you must first remove old races (often they can be tapped out with punches just reaching the inners faces of the old races on the frame or outer race on the fork stem.  It is important to try and tap them out centrally to avoid damaging/opening out bearing housings any more than necessary 

- When fitting new races, remove all traces of paint, rust or rough edges from the areas to receive the new races.  For the girder fork stem, check the inner face is not marked or worn and try and ensure the new race is placed over centrally - ideally they should be a light tap on.  To help with this the race can be warmed in an oven first.  If the fork stem bearing face is worn or damaged - a small amount of bearing fit fluid may help to retain them (this is not uncommon unfortunately, as original girder forks are now at least 75 years old)

- For fitting headraces into frames (or top crown) - again, ensure receptor area is fully cleaned of rust and dirt first.  It is important to ensure the greasing hole in the 3 races to go in frame and top crown are lined  up with the relevent grease nipple holes - otherwise it will not be possible to grease them in future without stripping

- To fit these races into frame and top crown - I first place races into a freezer for an hour or so (to contract as much as possible) and then normally use a soft aluminum drift, as shown in the photo - to ensure an even pressure is applied to the entire bearing face.  Do not hit bearing races directly with a hammer as this could damage them.  When tapping them in ensure they are seated squarly and fully down on the bottom face.  Pack races with clean grease on assembly

This listing is for a complete headrace bearing set, to fit those Norton models fitted with telescopic forks - from approximately 1947 to 1957. 

This type of headrace set was fitted to all rigid, plunger and swinging arm chassis - both Single Cylinder models and Domintor twins. 

Sorry, I am not an expert on later Featherbed roadgoing models and later twins - they may have continued to be the same type fitted to these models as well, so if you wish to fit these to a later model please email and we can provide dimensions.

The set consists of 4 hardened headrace bearings and two sets of ball bearings. Original Norton telescopic fork headraces (from Norton single 'Long' Roadholder forks) were used as the pattern for manufacturing these and all dimensions are the same to the originals.

The two frame races have a grease track and a small hole in the track, to allow for greasing from the frame.  The 3rd one of this type fits on the base of the fork stem (this still has a hole in the track - but fits flush against base of the fork crown - so hole is blind).  The fourth race does not have a greasing hole and the inner face of the bearing race is a larger diameter than the other 3 races.  This is to allow the large crown nut shoulder used on telescopic forks to slide fit into this inner bearing race face - see accompanyning photograph. 

It should be noted that between this top crown nut (which fits under the top stanchion crown) and the top headrace bearing is fitted a pressed steel cover, to stop dirt getting into the bearings.  There were two types of covers and we can provide these as well if required - the normal deeper roadgoing type (Item 0872 in our catalog) and a shallower version on Manx Norton models (Item 0873). 

As shown in the photographs bearing races are supplied with the ball race area smeared in Castrol moly grease to protect them from rusting in storage.  I find this is also a good grease to use for headraces on assembly (note in some photographs 2 bags of balls are shown - but there is one bag supplied with enough balls for two races + 1 additional ball in case you lose one on assembly)

Fitting Tips:

- To fit these races - you must first remove old races (often they can be tapped out with punches just reaching the inners faces of the old races on the frame or outer race on the fork stem.  It is important to try and tap them out centrally to avoid damaging/opening out bearing housings any more than necessary 

- When fitting new races, remove all traces of paint, rust or rough edges from the areas to receive the new races.  For the fork stem, check the inner face is not marked or worn and try and ensure the new race is placed over centrally - ideally they should be a light tap on.  To help with this the race can be warmed in an oven first.  If the fork stem bearing face is worn or damaged - a small amount of bearing fit fluid may help to retain them (I have a couple of original tele forks columns and found slight differences in wear on both - as they are many years old), but our races are made with the same inner race diameter as the original hardened race diameter.  On the steering stem in the photograph which has minimal wear, after cleaning the stem base and bearing retaining area, the bottom race went on with light taps with a rawhide mallet, tapping radially in turn, to ensure the race went on evenly

- For fitting headraces into frames - again, ensure receptor area is fully cleaned of rust and dirt first.  It is important to ensure the greasing hole in the 3 races to go in frame and top crown are lined  up with the relevent grease nipple holes - otherwise it will not be possible to grease them in future without stripping

- To fit these races into frame - I first place races into a freezer for an hour or so (to contract as much as possible) and then normally use a soft aluminum drift, as shown in the photo - to ensure an even pressure is applied to the entire bearing face.  Do not hit bearing races directly with a hammer as this could damage them.  When tapping them in ensure they are seated squarly and fully down on the bottom face.  Pack races with clean grease on assembly

These front engine plates are for Pre-Featherbed 500cc 30M/Manx models, using magnesium crankcases, and are fabricated using sided jigs (see pictures), to ensure they have the correct offset, form and hole location as original engine plates. All dimensions are copied from an original SOHC 500cc Manx engine plate

Background information:  Genuine Pre-Featherbed Norton racing models (from approximately 1935 onwards) used magnesium crankcases and had a different front engine mount on the frame downtube on both rigid and plunger models.  The front downtube engine mount on these frames sat approximately one inch (1") higher than their aluminium crankcased road going (International) SOHC counterparts.  Therefore these different type engine plates were required. 

Added to this, the magnesium (30M or early Manx) crankcase also had wider engine plate mounts at the front of the crankcase than aluminium International crankcases - that necessitated the engine plates being manufactured with a 'kink' in their sides, so they came in at the front to match the frame downtube lug. 

We have our engine plates lasercut - having used an original 30M (SOHC Manx) engine plate as the template - but we then have specially made jigs to allow them to be formed to the correct shape and profile - before the front engine bolt hole is then bored to the correct dimension on the jig.  This ensures these plates are always the correct dimensions (see accompanyning photos).

Finally, we lightly linish the edges (to remove any lasercutting marks) and lightly oil them to protect them from rust, before packing.  Price is for a pair of engine plates.

Final point for owners of 1948- 1950 350cc (40M) models - the 350cc 40M model used a crankcase that was physically slightly smaller than the 500cc 30M model (those using engine plates - Item 0202) - But sometime around 1948 Norton standardised the racing models on the 500cc type crankcase for both capacities - just having a smaller cylinder hole bored in the 350cc crankcases.  If you have a later set of pre-Featherbed 350cc Manx crankcases and are not sure which type they are - email us on sales@racingvincent.co.uk and we can help confirm for you - but if post 1948 350cc, then they are likely to require this type of front engine plate.

In the accompanying photographs is a picture of one of my own Manx Nortons (a 500cc plunger model) and you can see the distinctive engine plate fitted.  Note the top line of the plate is horizontal, where the 350cc model would have the top line sloping down towards the engine - one of the easiest ways to identify a 500cc from a 350cc model at a glance

These front engine plates are for Pre-1948 350cc 40M/Manx models, using magnesium crankcases, and are fabricated using sided jigs (see pictures), to ensure they have the correct offset, form and hole location as original engine plates. All dimensions are copied from an original SOHC 350cc Manx engine plate

Background information:  Genuine Pre-Featherbed Norton racing models (from approximately 1935 onwards) used magnesium crankcases and had a different front engine mount on the frame downtube on both rigid and plunger models.  The front downtube engine mount on these frames sat approximately one inch (1") higher than their aluminium crankcased road going (International) SOHC counterparts.  Therefore these different type engine plates were required. 

Added to this, the magnesium (40M or early Manx) crankcase also had wider engine plate mounts at the front of the crankcase than aluminium International crankcases - that necessitated the engine plates being manufactured with a 'kink' in their sides, so they came in at the front to match the frame downtube lug. 

We have our engine plates lasercut - having used an original 40M (SOHC Manx) engine plate as the template - but we then have specially made jigs to allow them to be formed to the correct shape and profile - before the front engine bolt hole is then bored to the correct dimension on the jig.  This ensures these plates are always the correct dimensions. See accompanying photos

Finally, we lightly linish the edges (to remove any lasercutting marks) and lightly oil them to protect them from rust, before packing.  Price is for a pair of engine plates.

Final point for these 350cc (40M) models - the 350cc 40M model used a crankcase that was physically slightly smaller than the 500cc 30M model (we also sell engine plates for that model - Item 0201) - therefore the engine plates shown here are different to the 500cc model.  However, sometime around 1948 Norton standardised the racing models on the 500cc type crankcase for both capacities - just having a smaller cylinder hole bored in the 350cc crankcases.  If you have a later set of pre-Featherbed 350cc Manx crankcases and are not sure which type they are - email us on sales@racingvincent.co.uk and we can help confirm for you.

In the accompanying photographs is a picture of a genuine (1936) Manx engine with one of these engine plates attached, and an original pre-war photograph of a 350cc 40M (Manx spec), which shows the engine plate - distinctive from the 500cc version in that its top face slopes down towards the engine, while the 500cc top face of the engine plate is horizontal

- These front engine plates are laser cut, giving an identical profile to the original 500cc pattern (which were often stamped 'JNB') that they are copied from.

They are exactly the same gauge as originals and come linished and lightly oiled.

Priced per Pair

- These front engine plates are laser cut, giving an identical profile to the original 350cc pattern (which were often stamped 'JNB') that they are copied from. They are exactly the same gauge as originals as well.

They come linished and lightly oiled.

Price is per pair

- These rear engine plates are laser cut, using an original engine plates as original, to fit 500cc Norton International and CS1 (aluminium) crankcases

- Note, these rear engine plates, as supplied, are to fit Racing International's - i.e. they do not have the cross tube and serrated washer fitted, as used on road based bikes (these can easily be welded on if you wish to do so).

- Note 2: I can supply these engine plates with the hole for the frame mount left blank if desired, as there is often some small discrepancy between original frames. I will also supply both sets if required, and you send back whichever set you do not use. Please request this when ordering.

Plates come linished and lightly oiled

Price is per pair