This section lists parts to fit OHV (Overhead Valve) and SV (Sidevalve) Norton parts, as well as a few items to fit Norton Dominator and Norton twin parts.

Update August 2018:  Having received many queries from OHV and SV owners in the last 3 years, we are now expanding our range to include many of the consumable parts for OHV/SV engines.  Having owned and restored numerous OHV and SV machines over the years, I still have a number of parts available for patterns - so email us on our normal sales@racingvincent.co.uk if you have a particular part you are trying to obtain and I can tell you if we are intending to manufacture in the forseeable future.  By the way, the picture shown here is of a 1955 Norton ES2 which was in our family from the mid 1960's.  It is shown here in the late 1980's following a full restoration, it being one of my favourite rides through much of the 1980's.

Please Note: We dont list all chassis and gearbox parts here - go to the relevent SOHC chassis and gearbox section - where a number of the parts are generic to all Norton singles.  Also, visit our Gasket section for a large selection of gaskets to fit both OHV and SV Norton single models - arranged chronologically after the SOHC Gaskets (although a few are common to all models, listed in the SOHC section).

This is the distinctively shaped Air Intake bellmouth and filter assembly - as fitted only to Norton OHV and SV model Amal 76/276 type carburettors from the 1930s until the 1950's. 

Because this intake/filter assembly were only fitted to Norton OHV/SV models (we assume Amal made them exclusively for Norton) - they are now particularly rare and sought after.  As well as the distinctively shaped bellmouth - originally there were 3 steel gauze filters fitted, and a distinctive spring clip to hold the filters in place.  Even if original Norton's still have the bellmouth in place - it is not uncommon to have one or all of the filters missing - or even more common - the original filters to have the gauze damaged or holes in them (see accompanyning photo of an original Norton bellmouth - with damaged gauze).  We have now reporoduced each of these compontents, with the same distinctive shape and dimensions of the original items.

We have had these bellmoouths, stainless steel gauze filters and stainless steel spring clips manufactured for us (all by specialised manufacturers in the UK) to the original style and pattern and they can be purchased as a complete assembly or components.

The only difference from originals - our intake move is machined from solid aluminum bar (the original item was the normal Amal pewter style material), while both our gauze filters and spring clips have been manufactured from stainless steel - so will not rust.  Our gauzes our manufactured for us by a specialist gauze filter manufacturer - and have the correct 'pressed round' rim of the original design.

It should be noted that the accompanyning original line drawing of the intake filter design - taken from the 1948 Norton Spare Parts List shows that originally - 3 filter gauzes were fitted as standard.  Therefore our 'Standard' version is also supplied with 3 filter gauzes.  However - the originla design of the bellmouth was such - that the bellmouth gauze retaining area was deep enough to hold 5 gauze filters.   So even the original Norton version (an original is shown in the photos) used to have the 'std' 3 filters loosely clipped - where they could move around slightly.  To combat this, we also supply a large diameter heat resistent 'O"-ring with each 3 filter assembly - which fits between the gauzes and the spring clip - and stops unnecessary movement.

I cannot be sure - but would guess that the original intention of making the bellmouth deep enough to accept 5 gauze filters - was because they were originally fitted to WD 16H models in the 1930's - when the UK were preparing for war.  Maybe they had anticipated the WD16H being used in hot sandy climates (North Africa etc - 8th Army) - and had designed the bellmouth to take a maximum of 5 filters for this reason.  With that in mind, one of the variations shown is to purchase an additional 2 filters, as well as the 3 filter kit.  If you order both these items - the two additional filters will be slightly cheaper than buying them individually - and the O ring in the bellmouth kit can be replaced with the 2 additional filters.  Of course - it is up to the customer to decide if the filters fitted might affect the carburettion jetting - but having trial blown through a bellmouth with 5 filters fitted - it still seemed to give little air resistence. 

This is a variable listing - where you can purchase the complete assembly ready to fit to your carburettor - or if you have the original bellmouth already - but have missing or damaged filters, or spring clip is missing - we also sell these items seperately.

These assemblies are manufactured for us in the UK, to the original dimensions - which were adopted from (approximately) the late 1930's through to the introduction of the monobloc carburettor (note - sorry this filter is designed specifically for the Amal 76/276 type carb - it will not fit the later monoblock carburettor)

Item Details:

This is a 79.62mm (500cc) forged slipper piston which copies the same vital dimensions as the original 1940's-50's Norton Heplex 572 OHV (Model 18 and ES2) piston, other than having a slightly raised crown - which on most OHV models should relate to an estimated circa 8:1  compression ratio.  As with our SOHC slipper pistons - these are the highest quality forged slipper pistons made by top manufactuer Omega.  

Price is per piston - piston includes rings, Gudgeon Pin and circlips

Background Information:

As can be seen in the accompanyning photographs - original post war (Heplex) OHV Model 18 and ES2 pistons were most often of the full skirt and flat dome variety - as per the original Norton OHV piston in the photo (taken from a late 1940's standard ES2 many years ago).

The most importand dimensions which we have copied into these Omega pistons are the correct Gudgeon Pin Diameter, the width of the OHV/SV con rod Little End distance and most importantly - height from the centre of the gudgeon pin to the base of the piston crown, and with this, the same base piston crown chamfer as the original Heplex Model 18/ES2 piston. 

However, we have had these pistons made with a slightly raised crown in the centre -  raised by 10mm at the centre, which should provide a compression ratio of approximately 8:1 (as original pistons and motor specifications in the 1940's were more suited for the lower quality petrol available at the time).  As can be seen - the valve cutaways have also been enlarged slightly to allow for this.

Norton Side Valve 16H piston usage: It should be noted that the WD side valve 16H Norton, and the later Postward 16H models, all used a piston similar to the ES2, but this piston also had a raised crown, to achieve a similar compression ratio to the OHV model in the larger SV combustion space (but of course, original 16H pistons did not have the need for valve cutaways and were normally of a more heavyweight skirt construction for long life.  The construction of these Omega pistons may make them lighter than original 16H pre-war pistons (although post-war type were lighter and comparable) - but are a viable alternative to be considered for 500cc 16H sidevalve models.  A picture of an original WD sidevalve piston is shown in the accmpnanying photos for comparison

Norton CS1 (SOHC) Usage:  These pistons are similar to the higher compression 'International' pistons we also offer (Item 0396 and 0397), but with slightly different dome dimensions (and of course, a lower compression ratio than the International type).  If you have either a Walter Moore or Arthur Carroll type CS1, and are looking for a lower compression version of our International piston, then email us on sales@racingvincent.co.uk to confirm if these will fit your engine 

Norton Late SOHC Inter/Manx 500cc (Early 50's) Usage:  It should be noted that our main SOHC pistons (Item 0396-0398) are intended for the 'deep barrel spigot' type Inter/SOHC Manx engine, which was used on most SOHC engines until sometime in the late '40's/early 50's.  At some point around this time a shallower barrel spigot and combustion chamber seems to have been adopted.  We do not offer a piston specifically for that later 'shallow barrel spigot' type 500cc SOHC engine, but if you have an engine of that later type - this piston may turn out to be more suitable to adopt.  It is important to measure the height between the centre point of the gudgeon pin and the top lip of the barrel to confirm the type of piston required - if unsure - please email us and we can confirm the important dimensions of this piston. It is important to check this beforehand - as unfortunately we cannot accept returns once a piston has been removed from its packaging and trial fitted.

As a final point - although most people associate 'Slipper' type pistons with racing engines - but for all uses, they are a high quality forged piston that have a steady and reliable expansion rate and are very stiff and rigid in construction.  And surprisingly - the total 'touching' side wall of the thrust face of these Omega pistons is actually fractionally more than the original Heplex 572 Norton piston shown in the photograph.

Fitting Pistons: As with the fitting of all pistons to older engines (which may have been previously modified) - we strongly advise you satisfy yourself there is sufficient piston to head/clearance in your own engine when fitting one of these pistons - I always put a thin layer of plasticine on the top of a piston crown - then slowy turn the assembled engine over by hand first - there should be at least 60 thou of clearance on valve cutaways and to ensure the piston is not touching the head at any point.  a Digital caliper, using the depth gauge prong into the plasticine is ideal for this.  

Piston Weight: These pistons weigh 450grams complete with Gudgeon Pi, rings and circlips - which is within a couple of grams of the weight of the original Norton Heplex 572 piston (unlike other non forged modern OHV substitutes, which are considerably heavier).  Therefore the balance charateristics when using these pistons should be comparable to original specification 

Little End Width: This listing is for a piston to fit a Norton OHV/SV or CS1 specification engine - i.e. the piston is designed to take the Norton conrod which has a Little End width of 1.200"

Bore Size Information: 

Original OHV and SV Norton (Longstroke) 500cc pistons had a standard bore of 79mm, and were then offered in standard oversizes of +20, +40 and +60 thousandths of an inch.  Occasionally +30 thou oversize can also be found.

We can currently only offer these pistons in two bore sizes - 79.62mm (which is this Item listing) or 80.13mm (Item 1062)

79.62mm in OHV/SV oversize parlance can be converted to 79mm + 24thou, while the 80.13mm version can be converted to 79mm + 44thou.  Hopefully one of these two 79mm oversizes will be suitable for your engine (or of course you can consider re-lining your cylinder if already out at +60.  If based in the UK we can recommend people we have used for this in the past).

When taking your barrel to be bored/honed, ask for the barrel to be honed to the exact size shown on here (79.62mm or 80.13mm), Omega will have worked out the correct clearances for these pistons for that bore.

In case you are wondering why we have chosen these two bore sizes for our pistons - our original Omega forge patterns were made for the Manx Norton piston size of 79.62mm and one oversize of this - as original Manx Longstroke pistons were a slightly larger bore, to allow the full 499cc capacity to be used for Grand Prix racing.  These two sizes also allowed a useful 'oversize' piston for standard 79mm engines.

This is a 79.62mm (i.e. 79.62mm +20thou oversize) 500cc forged slipper piston which copies the same vital dimensions as the original 1940's-50's Norton Heplex 572 OHV (Model 18 and ES2) piston, other than having a slightly raised crown - which on most OHV models should relate to an estimated circa 8:1  compression ratio.  As with our SOHC slipper pistons - these are the highest quality forged slipper pistons made by top manufactuer Omega.  

Price is per piston - piston includes rings, Gudgeon Pin and circlips

Background Information:

As can be seen in the accompanyning photographs - original post war (Heplex) OHV Model 18 and ES2 pistons were most often of the full skirt and flat dome variety - as per the original Norton OHV piston in the photo (taken from a late 1940's standard ES2 many years ago).

The most importand dimensions which we have copied into these Omega pistons are the correct Gudgeon Pin Diameter, the width of the OHV/SV con rod Little End distance and most importantly - height from the centre of the gudgeon pin to the base of the piston crown, and with this, the same base piston crown chamfer as the original Heplex Model 18/ES2 piston. 

However, we have had these pistons made with a slightly raised crown in the centre -  raised by 10mm at the centre, which should provide a compression ratio of approximately 8:1 (as original pistons and motor specifications in the 1940's were more suited for the lower quality petrol available at the time).  As can be seen - the valve cutaways have also been enlarged slightly to allow for this.

Norton Side Valve 16H piston usage: It should be noted that the WD side valve 16H Norton, and the later Postward 16H models, all used a piston similar to the ES2, but this piston also had a raised crown, to achieve a similar compression ratio to the OHV model in the larger SV combustion space (but of course, original 16H pistons did not have the need for valve cutaways and were normally of a more heavyweight skirt construction for long life.  The construction of these Omega pistons may make them lighter than original 16H pre-war pistons (although post-war type were lighter and comparable) - but are a viable alternative to be considered for 500cc 16H sidevalve models.  A picture of an original WD sidevalve piston is shown in the accmpnanying photos for comparison

Norton CS1 (SOHC) Usage:  These pistons are similar to the higher compression 'International' pistons we also offer (Item 0396 and 0397), but with slightly different dome dimensions (and of course, a lower compression ratio than the International type).  If you have either a Walter Moore or Arthur Carroll type CS1, and are looking for a lower compression version of our International piston, then email us on sales@racingvincent.co.uk to confirm if these will fit your engine 

Norton Late SOHC Inter/Manx 500cc (Early 50's) Usage:  It should be noted that our main SOHC pistons (Item 0396-0398) are intended for the 'deep barrel spigot' type Inter/SOHC Manx engine, which was used on most SOHC engines until sometime in the late '40's/early 50's.  At some point around this time a shallower barrel spigot and combustion chamber seems to have been adopted.  We do not offer a piston specifically for that later 'shallow barrel spigot' type 500cc SOHC engine, but if you have an engine of that later type - this piston may turn out to be more suitable to adopt.  It is important to measure the height between the centre point of the gudgeon pin and the top lip of the barrel to confirm the type of piston required - if unsure - please email us and we can confirm the important dimensions of this piston. It is important to check this beforehand - as unfortunately we cannot accept returns once a piston has been removed from its packaging and trial fitted.

As a final point - although most people associate 'Slipper' type pistons with racing engines - they are a high quality forged piston that have a steady and reliable expansion rate and are very stiff and rigid in construction.  And surprisingly - the total 'touching' side wall of the thrust face of these Omega pistons is actually fractionally more than the original Heplex 572 Norton piston shown in the photograph.

Fitting Pistons: As with the fitting of all pistons to older engines (which may have been previously modified) - we strongly advise you satisfy yourself there is sufficient piston to head/clearance in your own engine when fitting one of these pistons - I always put a thin layer of plasticine on the top of a piston crown - then slowy turn the assembled engine over by hand first - there should be at least 60 thou of clearance on valve cutaways and to ensure the piston is not touching the head at any point.  a Digital caliper, using the depth gauge prong into the plasticine is ideal for this.  

Piston Weight: These pistons weigh 450grams complete with Gudgeon Pi, rings and circlips - which is within a couple of grams of the weight of the original Norton Heplex 572 piston (unlike other non forged modern OHV substitutes, which are considerably heavier).  Therefore the balance charateristics when using these pistons should be comparable to original specification 

Little End Width: This listing is for a piston to fit a Norton OHV/SV or CS1 specification engine - i.e. the piston is designed to take the Norton conrod which has a Little End width of 1.200"

Bore Size Information: 

Original OHV and SV Norton (Longstroke) 500cc pistons had a standard bore of 79mm, and were then offered in standard oversizes of +20, +40 and +60 thousandths of an inch.  Occasionally +30 thou oversize can also be found.

We can currently only offer these pistons in two bore sizes - 79.62mm (Item 1061) or 80.13mm (this item listing)

79.62mm in OHV/SV oversize parlance can be converted to 79mm + 24thou, while the 80.13mm version can be converted to 79mm + 44thou.  Hopefully one of these two 79mm oversizes will be suitable for your engine (or of course you can consider re-lining your cylinder if already out at +60.  If based in the UK we can recommend people we have used for this in the past).

When taking your barrel to be bored/honed, ask for the barrel to be honed to the exact size shown on here (79.62mm or 80.13mm), Omega will have worked out the correct clearances for these pistons for that bore.

In case you are wondering why we have chosen these two bore sizes for our pistons - our original Omega forge patterns were made for the Manx Norton piston size of 79.62mm and one oversize of this - as original Manx Longstroke pistons were a slightly larger bore, to allow the full 499cc capacity to be used for Grand Prix racing.  These two sizes also allowed a useful 'oversize' piston for standard 79mm engines.

This is a listing for the Little End Bush to fit Norton Single Cylinder models - with 4 variation types.  They are available to fit most SOHC models (road going and competition type), OHV and SV models.  We also manufacture a type to allow the fitment of BSA type pistons, with 0.750" Gudgeon Pin diameter. 

We manufacture these Little End bushes in a high quality Leaded Bronze - PB2 (which has a higher Tin content than others to give very hard wearing properties), and is widely regarded as the best material for Little End manufacture (and of course more expensive than many other bronze types).

We manufacture these Little End bushes to the 'Standard' Norton outer diameter tolerance that would have been used when they were first manufactured - therefore when fitting these bushes to your Con Rod, it is important to confirm the condition of your con rod Little End Eye, and to confirm the condition and diameter of the old Little End bearing your are removing - to ensure it has not gone oval from excessive use or age . . . and to confirm that the the Outer Diameter of our Little End Bush (which are CNC machined to a very close tolerance of the original Norton 'STD' tolerance interference fit), are at least the same diameter as the bush being removed - in case your own Con Rod has already had an oversize Little End fitted in the past. 

Sorry, but we cannot accept Returns on these items once any attempt to fit them has been made (as they will always mark in the process of fitting) - so please ensure you have confirmed dimensions before attempting to fit.

All four types of Little End bushes have a shallow 'coarse scroll' innner oil way running across their width - as per original Norton Little Ends, to aid oiling.

All 4 types of Little Ends have been manufactured to very accurate tolerances - and examples have been 'Test fitted' into original Norton conrods.  The internal bore tolerance of the bushes has been set so that once pressed into a 'Standard' Norton fit con-rod, and any burr's from pressing removed. that a standard Norton Gudgeon Pin will just slide into the bush.  However - as with all Norton parts - con rod tolerances can vary - so you must check the bush after fitting, to ensure the gudgeon pin will turn smoothly in the bore of the new bush.  (As with fitting any plain Little End bush) - if there is any tightness of the Gudgeon pin, it may require gentle hand scraping or light reaming (with lots of light cutting oil), to ensure the pin will spin freely 

Four Types of Little End are currently available, with the following details:

1077_1: Standard SOHC (International), OHV or SV Type - Already pre-drilled with Standard Norton 'Diamond' Type Oil Holes:

This is the 'standard' roadgoing type Little end, to accept Norton 0.875" Gudgeon Pin piston, with 1.150" width con rod Little End eye width (this can vary by @+/- 10 thou by conrod - as this type of Little End was used on most roadgoing Norton single cylinder models over a 30 year period - from early 1930s to late 1950's).  These little ends have the 'regular' Norton 'Diamond' pattern 4 oiling holes pre-drilled, for those customers who would prefer not to drill the holes themselves after pressing the new Little End into the conrod.  However, this means a little more care must be taken when fitting the new Little End bush, to ensure the oil holes in the bush are in-line with those in the conrod - this can be easily achieved by using a permanent felt pen to draw lines over the top of the conrod.  The holes in our bush have been copied exactly from an original Norton bush - and pressed into an original Norton con rod - to ensure they line up.  However, as per the width, there were fractional variations on con rods over the years - so the holes can vary fractionally.  It is not critical if a hole does not line up exactly - providing each of the 4 holes are close and still allow oil to flow through

- Gudgeon Pin Diameter:  0.875"

- Width: 1.150"

- Oil Holes: 4 Hole Diamond Pattern Pre-Drilled

Weight of Little End: 38 gram (as per original)                 

1077_2: Standard SOHC (International), OHV or SV Type - Without Standard Norton 'Diamond' Type Oil Holes:

This is the 'standard' roadgoing type Little end, to accept Norton 0.875" Gudgeon Pin piston, with 1.150" width con rod Little End eye, as per the 1077_1 version - however, this Little End bush does not come with the 'Diamond' type oil holes pre-drilled, instead, this type is intended to be pressed in - then the customer can drill the 4 oil holes to exactly match the con rod of their bike.

This was historically the more 'normal'  way of ensuring the 4 oil holes match your con-rod exactly - because you would wait until you had pressed the new bush into position - then use the existing con rod oil holes as a 'guide' for drilling the holes in the bush.  This is great if you are confident in drilling the holes yourself *(and then gently hand scraping the resulting burrs from the bore of the bush), but if you already have the con rod fitted into a crank or engine - you may be worried about the resulting 'swarf' going into the engine - in which case 1077_1 may be easier.  Both types are the same in other respects

- Gudgeon Pin Diameter:  0.875"

- Width: 1.150"

- Oil Holes: Not Drilled - therefore positioning before pressing is less critical, but customer drills oil holes after fitting

- Weight of Little End: 40 gram (this will reduced to 38g after drilling oil holes)       

1077_3: M30/40 or Manx SOHC (and Longstroke DOHC) Type Little End - non-drillled oil holes:

This is the 'Racing' type Little end - as fitted to Longstroke magnesium crankcase racing engines - which like road models used an  0.875" Gudgeon Pin piston, but had a narrower width than roadgoing models - i.e. a 1.010" width con rod Little End eye.  (Again, tolerances may vary on your con rod by +/-10 thou, but the con rod Little End eye width should be approximately 1.00", and the piston similar.

Other vital dimensions for this type of Little End bush are as per 1077_1 and 1077_2 - but for this 'Racing' (Manx) type Little End, the oil holes are not pre-drilled, as racing (Manx) con rods have had slight variations on their oil holes over the years they were fitted.  Therefore the oil holes will need to be drilled by the customer to suit your individual con rod after fitting.  However - as a rule, genuine Lonstroke Manx rods normally had a minimum of two oil holes on the top of the rod - drilled in the centre line.  Because of the reduced width of the Manx conrod Little End eye, the diamond pattern was not used

(note - if you have one of these narrow rods, but with a Diamond oil pattern already drilled - chances are it started life as an Inter Con Rod and has been modified to fit an M30/Manx by a previous owner - not a good idea as it weakens the eye! - I have at least one of these in my collection!)

- Gudgeon Pin Diameter:  0.875"

- Width: 1.010"

- Oil Holes: Not Drilled - To be drilled by customer after pressing to their own con-rod oil hole pattern

- Weight of Little End: 34 gram (this will reduced further once oil holes drilled)       

1077_4: Standard SOHC (International), OHV or SV Type Width - But bored to receive a (non Norton) 0.750* Gudgeon Pin:

Due to the limited availabilty of replacement pistons for Norton single models over the years - it is not unusual for owners to have fitted similar dimension pistons from other Marques to their engines.  One of the most common 'substitute marques' to be used are BSA pistons - which most commonly, are fitted with a smaller diameter 0.750" Gudgeon Pin (i.e. BSA B40, B44 or B50 pistons in 500cc Norton OHV engines, or BSA twin pistons in 350cc Norton singles - all these piston types being fitted with 0.750" Gudgeon Pins).

This variation of Little End bush is to the same vital dimensions as 1077_2 in all other respects, but has a smaller Gudgeon Pin hole of 0.750", in case you have a standard width roadgoing SV.OHV, SOHC con rod - but wish to fit a piston as described above.

As with 1077_2 - the top oil way holes have not been drilled on this Little End Type - it being for the customer to do this after fitting.

Also - it must be remembered that this Little End will be slightly heavier than a standard Norton Little End and may affect the Balance Factor of the engine.  However - this may well be balanced out by the piston - so all piston components and Little End should be compared to the equivelant Norton components to work out if any re-balancing would be preferable  

- Gudgeon Pin Diameter:  0.750"

- Width: 1.150"

- Oil Holes: Not Drilled - customer drills oil holes after fitting

- Weight of Little End: 68 gram (this will reduce slightly after oil holes drilled)       

Price for all 4 variations is - Each.

Email sales@racingvincent.co.uk if you require more technical information on how to remove old Little End bushes, and fit new ones - but it would be expected that anyone attempting this task is familiar with engine build work and has a good understanding of this type of task already - or is trusting the task to an experienced engine builder

Manufactured by a well established and specialist British bearing supplier who have been making these Bigends for many years - this Bigend is of the same design and specification as the original 1930's - late 1950's OHV and SV design - this being a twin row, crowded roller design (i.e. the rollers do not sit in a cage).

These BigEnds come supplied 'hot dipped' in protective grease as per photograph, as a complete assembled unit and include the Bigend Nuts as well.

A typical OHV mid-1950's crankshaft is shown in the second photo (this being from a 600cc Model 19) - but this Bigend is of the type fitted to all OHV and SV models from the 1930's to the late 1950's - i.e: Model 18, ES2, Model 19, 500T, Model 50 (350cc), 16H and Big 4.  Email us at sales@racingvincent.co.uk if you are unsure if this will fit your model 

Update Feb 2021: We are now offering these OHV/SV Bigends, from the same manufacturer that has provided our SOHC BigEnds for many years.  If you wish to have these Bigends fitted and the outer race honed by us - then contact us at sales@racingvincent.co.uk for availability and turnaround time (we have offered this service for SOHC conrods for many years).

FYI - If these are showing out of stock - it normally means we have a new batch on order, so feel free to order and we will email when a new batch is expected in - this normally is no longer than 1 - 2 months from showing out of stock

If you wish to use your OHV engine for high performance work, we also offer a 'caged roller' version of the same Bigend - see Item 0864 

Manufactured by a well established and specialist British bearing supplier who have been making these Bigends for many years - this particular Bigend is of modified 'Caged Roller' design - more suited to high performance than the original Crowded Roller type.  Comes complete with BigEnd nuts.

The overall dimensions of this Bigend are as per the original - so can be fitted to standard crankshafts without any modification - but like SOHC engines, they have rollers running in a cage - which means they are less likely to rub and overheat.  They are more suited to an OHV engine that is being used for prolonged high speed usage or performance events.  (However - do not forget:  OHV and SV engines were originally fitted with Cast Iron flywheels - not steel flywheels like the OHC engines, therefore you still need to bear this in mind - from my own experiences racing OHV engines, I know the flywheels are often the limiting factor!).  

These BigEnds come supplied 'hot dipped' in protective grease as per photograph, as a complete assembled unit and include the Bigend Nuts as well.

A typical OHV mid-1950's crankshaft is shown in the second photo (this being from a 600cc Model 19) - but this Bigend is of the type fitted to all OHV and SV models from the 1930's to the late 1950's - i.e: Model 18, ES2, Model 19, 500T, Model 50 (350cc), 16H and Big 4.  Email us at sales@racingvincent.co.uk if you are unsure if this will fit your model 

Update Feb 2021: We are now offering these OHV/SV Bigends, from the same manufacturer that has provided our SOHC BigEnds for many years.  If you wish to have these Bigends fitted and the outer race honed by us - then contact us at sales@racingvincent.co.uk for availability and turnaround time (we have offered this service for SOHC conrods for many years).

FYI - If these are showing out of stock - it normally means we have a new batch on order, so feel free to order and we will email when a new batch is expected in - this normally is no longer than 1 - 2 months from showing out of stock

We also offer a similar OHV/SV BigEnd with the original type 'Crowded Roller' design, which is slightly cheaper - Item 0863

Manufactured by a well established and specialist British bearing supplier who have been making these Bigends for many years - these Big End Nuts are to fit the standard OHV and SideValve Norton Big Ends.   

Price is Each

We sell complete OHV/SV Big Ends complete in two guises - Original (uncagegd) type - Item 0863 and Modified (caged) type  - Item 0864, both of which complete with the same nuts as shown here, but if for any reason you need a spare nut (or have damaged an original Big end nut, as often happens) - then these nuts should fit most original Norton OHV/SV Bigends.

Note, if buying these nuts to fit an original Big End - please email first to confirm thread details (as there have been many aftermarket manufacturers of Bigends over the years - and some may have used non original threads) 

- Single row ball bearing. Fitted to all pushrod and sidevalve engines (from 1930's to late 1950's). These are original high quality RHP bearings (plastic sealed), in the correct C3 fit - now extremely difficult to find

Update Feb 2021: As previously updated, these OHV/SV ball main bearings - from original manufacturer RHP, in the correect 'looser tolerance' C3 fit are now just as rare as the corresponding SOHC versions, and obsoleteu/unobtainable.  We sold our last stock at the end of 2020.

We are waiting for an update on a small delivery of the correct RHP C3 (with price expected to be @£110 each), but if you wish to reserve one now, please email us on sales@racingvincent.co.uk

It is worth noting that we also have a few of the same bearing from RHP, but in 'standard' fit - this is Item 0733.  This is exactly the same high quality bearing, but it is not quite as 'loose' when new as the C3 fit.  This just means you need to be a little bit more careful when running the bike in, to let them wear in first - so to avoid the bearing spinning in the crankcase bearing housing.  If you think you have a crankcase where the bearing may have previously spun in the housing (and the alloy bearing housing looks slightly grey or worn) - then I would advise paying the extra money and going for the C3 fit listed here - while they are still available.

Failing both options above, we may be able to obtain these bearings from one of the modern lesser brands in the near future - again, email us for details.

Final point on ball and roller main bearings fitted to 1930's/50's OHV and SV engines: Unusually, Norton's showed a roller bearing being fitted on both sides of the crankcases on OHV/SV engines (i.e. 1948 catalog), with a ball bearing fitted just on the outer drive side.  However, I have stripped OHV engines down in the past where a ball bearing is fitted both sides, with just the drive side inner being a roller bearing.  Not sure if it makes a great deal of difference - as like the SOHC engine, the OHV/SV engine was locked to the timing side bearing - but worth noting if you are struggling to find two roller bearings

- Single row ball bearing. Fitted to all pushrod and sidevalve engines (from 1930's to late 1950's). These are original high quality RHP bearings (plastic sealed)- but are in a 'standard' fit, not the original looser C3 fit.  Feb 19: Read detail lisitng for update

Update Feb 2019:  We do sell the correct C3 fit version of this bearing, which Norton originally fitted - that is Item 0242, but stocks of that bearing are extremely limited, and if sold out, or you feel comfortable to fit the standard fit type listed here (which is slightly cheaper), then this is still the high quality RHP brand and still an excellent bearing.

Just like the even harder to find 'C3' version of this bearing - these bearings are now obsolete and very difficult to find, I only have a few of these left and once they are gone am not sure if I will be able to obtain more.

Fitting a 'non C3' bearing just means you need to be a little bit more careful when running the bike in, to let them wear in first - so to avoid the bearing spinning in the crankcase bearing housing.  If you think you have a crankcase where the bearing may have previously spun in the housing (and the alloy bearing housing looks slightly grey or worn) - then I would advise paying the extra money and going for the C3 fit listing - Item 0233 - while they are still available.

Final point on ball and roller main bearings fitted to 1930's/50's OHV and SV engines: Unusually, Norton's showed a roller bearing being fitted on both sides of the crankcases on OHV/SV engines (i.e. 1948 catalog), with a ball bearing fitted just on the outer drive side.  However, I have stripped OHV engines down in the past where a ball bearing is fitted both sides, with just the drive side inner being a roller bearing.  Not sure if it makes a great deal of difference - as like the SOHC engine, the OHV/SV engine was locked to the timing side bearing - but worth noting if you are struggling to find two roller bearings