- Silversteel roller that secures the two cams together. Quite a difficult piece to make, as it has a tight length tolerence - to avoid the issue of the cams not fully mating together (too long), or there not been enough protruding from both cams (too short).

SOHC Camshaft to fit all standard Model 30/40/International and CS1/CJ camshafts - This camshaft is for the standard (side oil feed) cambox type bikes.

This camshaft is of the 'solid' type, i.e. it does not have the central oil feed hole - instead relying on oil from the cambox oil pipe feeding along a groove in the spacer ring externally.  If your cambox is the road going sort - where the front bevel cover is smooth and does not have any central feed boss, then this is the correct camshaft for your engine.

Update Sept 2023:  Sorry these are now out of stock, but we should shortly be having a new batch made - should be approximately 3 months lead time and we may ask for a deposit.  Email paul.norman@racingvincent.co.uk for more information

However (if we are showing out of stock of this item) - it is possible to use the racing type camshaft (i.e. centre oil feed) in a non central oil feed cambox - it just means the central oil feed holes will not be used.

 

SOHC Camshaft to fit all central oil feed racing camshaft engines - This camshaft has provision for a central oil feed, as used on racing and competitionengines. 

This type of SOHC camshaft differs from the solid type, in that is bored through the centre allowing for a central oil feed directly onto the lobe of the cams.  This is the correct fitting for SOHC cambox's that have provision for the central oil feed on the front bevel cover.

It should be noted that early competition cambox's are identifiable by having the central oil plunger boss, but the castings are in aluminium.  However, with the introduction of magnesium for competition bikes in approximately 1935-36, it is more normal for this type of camshaft to be used on magnesium cambox's, where the front bevel cover was also magnesium and always came with the central oil plunger boss.  This 'competition' type of cambox is easily identifiable from roadgoing cambox's in that the oil feed union uses the lower of the two bosses cast into the cambox, while the non-central feed road going type uses the upper boss.  It is possible to drill oilways into a roadgoing cambox to give a central feed, but it is not an easy job to do and requires being very careful to ensure oilways are drilled in line with a central feed front bevel cover (which we do offer in magnesium)

It is possible though to use this central oil feed type camshaft in a standard Inter cambox, providing the original roadgoing oil supply is used - although it offers no real benefit, other than saving a fraction of weight.

Final point on SOHC magnesium cambox's with central oil feed: it seems that nearly all later roadgoing International's were fitted with the magnesium cambox with central oil feed - particularly Featherbed models.  This was probably because Norton had moved over to DOHC engines for racing from 1951 and had stocks of their SOHC Manx cambox's still in stock to use up.  If you are unsure if your cambox is this type, and want to check before purchasing - email us at sales@racingvincent.co.uk

 

This is the distinctive slotted spacer ring that fits over the camshaft in the tunnel area between the front (bevel gear) chamber and the rear (cam) chamber. On racing cambox's that employ the centrally fed camshaft oilway, this is no more than a spacer ring, however, for the road going type cambox, which uses a solid camshaft, this spacer ring is very important as oil is fed to the cam chamber along the slot. For this reason, there is a slight lip one one end, to ensure the bush can only be fitted in one direction

Essential when rebuilding your engine to ensure that the upper vertical bevel gear has the correct backlash and position in relation to the camshaft bevel gear, these camshaft bevel shims fit between the camshaft and the front cambox bearing (i.e. in the front cambox well).

Fitted in conjunction with the upper vertical bevel gear shim, the ideal positioning is acheved when the gears are in line and there is a just perceptible gap (backlash) between teeth.

This is for a set of 3 shims in the following sizes :

0.2mm/0.3mm/0.5mm. Note - shim steel is now supplied in metric thicknesses, but these are offered in the nearest equivelant to the old Imperial sizes that were commonly used - i.e.

- 0.3mm = 0.012" or 12 thou

- 0.2mm = 0.008" or 8 thou

It is common practice to measure initially with no shims fitted, then add one or multiple shims to reach the desired final positive backlash, measuring each time shims are added or subtracted  

Note: The A11/788 back distance piece is sold seperately - see Item 0329, as can these shims in the individual sizes (Item 0328).  The back distance piece is not used for shimming the camshaft bevel gear - it is for setting distance of cambox back bearing correctly.

Please note - Oct 2022 . . .in the past we used to get these made in 5 different thicknesses - but now only available in 3  most common sizes . . . but you may find it prudent to buy more than one packet or some additional individual shims - I normally keep a small tub of them, to ensure I can make up the right combination for correctly shimming the cambox I am making up, as over the 30 year period these cambox's were made, it is rare to find two cambox's with the same shimming requirement! 

In the accompanyning photographs - the second photograph shows our shims on one of our camshafts in the position the shims would fit before the camshaft is slid into the cambox - the shims being fitted between the camshaft shoulder and the front cambox bearing (i.e. adding more shims pushes the large bevel gear out from the bearing more).

The final photograph shows a genuine pre-war (Manx) camshaft . . . having just been stripped for the first time in 50 years, and original Norton shims still in place (and a similar photograph is also shown in the listing for Item 0329, as the distance piece is also in situ in that photograph)

Essential when rebuilding your engine to ensure that the upper vertical bevel gear has the correct backlash and position in relation to the camshaft bevel gear, these camshaft bevel shims fit between the camshaft and the front cambox bearing (i.e. in the front cambox well).

Fitted in conjunction with the upper vertical bevel gear shim, the ideal positioning is acheved when the gears are in line and there is a just perceptible gap (backlash) between teeth.

This is for a single shim in one of the following sizes - state which size required when ordering:

- 0.5mm = 0.021" or 21 thou (for some reason the actual thickness is 0.53mm which = 21 thou) 

- 0.3mm = 0.012" or 12 thou

- 0.2mm = 0.008" or 8 thou

- 0.1mm = 0.004" or 4 thou

- 0.05mm = 0.002" or 2 thou

It is common practice to measure initially with no shims fitted, then add one or multiple shims to reach the desired final positive backlash, measuring each time shims are added or subtracted  

This is the distance piece that betweens the cams and the cambox back bearing.

It ensures the back bearing inner cage and rollers are sititng centrally in the outer bearing (which is located in the cambox rear cover).

Assembly Note: This distance piece has been copied from an original pattern - taken from a very original pre-war SOHC M30 (magnesium) racing cambox, which has not been apart for at least 50 years before I stripped it down - and as you see here our distance piece looks just the same as the original.  However, you will also notice that the spacer has a slot to feed over the camshaft woodruff key, that retains the cams.  

I am not sure why Norton's did this, as it is normal for the the spacer ring to be fitted between the cam and rear cambox bearing (i.e. before you get to the woodruff key), however what is most important is to ensure the cams are running as close to central under the rockers - so I assume that Norton's did this because there may have been some variations, whereby it was possible to fit this ring behind the cams if necessary - to ensure they are central to rockers.  However, for initial assembly - I always follow the 1948 Spare Parts list exploded diagram and fit it initially between cam and back bearing.You should always check that the cams are acting on the rockers close to central and not fouling the other rocker.

This distance piece is @60 thou thick, which I find to normally be correct, but you should check yourself that this thickness locates the bearing in the correct position, as this can sometimes vary as there were many slight variations over the years. To help with this, place thick high melting point grease in the outer cage of the back bearing, then trial fit the back cover, you can then see from the marks in the grease if the inner race is in the correct position.

Note:  This distance piece has nothing to do with setting the camshaft/vertical bevel gear mesh - for those shims, see Item 0328 and 0328B

- Single row ball bearing. Fitted to all SOHC engines, both International and early Manx. 

These are either high quality RHP or SKF bearings -dependent on availability at the time - but both these manufacturers supply bearings of the highest quality. 

Orginally fitment for this front cambox bearing would have been 'C3' looser fit bearings - but those are now unobtainable, and often were not r-fitted once changed anyway.  These are the 'standard' fit type, but this should not really make a great deal of difference on this bearing - just give it a little more time to run in after fitting.  It is far better to fit good quality RHP/SKF bearings - than an inferior quality non UK bearing.

Note:  It us not unusual when stripping both SOHC and DOHC Manx Norton engines (i.e. racing engines) to find a slot ground into the outer race of this bearing, approximately 1/16" deep.  Then when fitting the 3 screw plate over this bearing on assembly - a screwdriver used to punch an indent on the bearing plate that corresponds with this slot.  This is done to make sure there is no chance of the bearing spinning in the housing.  Although I cannot advocate this being good engineering practice . . . I know I do it on all my engines built for racing!- also on main bearings (if you do do it - make sure you cover bearing with cling film or similar first, so nothing gets in bearing).  

- Single row caged roller bearing. Fitted to Model 30/40 (International) SOHC engines. These are either RHP or Hoffman (Hoffman became RHP) - both best quality and in correct and very difficult to find C3 fit.

(C3 type are slightly looser tolerance bearings and were originally used in these racing engines. The C3 type are not essential for cambox's - but are definitely a rare luxury today, when even the standard RHP type have been unavailable for the last couple of years). Not cheap - but the proper thing and when they are gone they are gone!!

Note this bearing, fitted to International Nortons is bigger than the bearing fitted to SOHC magnesium cambox backplates. This bearing is 1.812" outer diameter - to fit SOHC aluminium cambox's, in case you are not sure which bearing you require. 

Cambox Bearing - Camshaft Back Roller Bearing : as fitted to the Model 30M/40M (Manx) cambox backplate - identifiable from the standard International type, in that the Manx backplate is in magnesium.

These are the correct RHP C3 bearings - now unobtainable and very difficult and expensive to obtain.  These are the genuine areticle and therefore not cheap - apologies for price, but hope you would agree, it is much better to pay the price for the proper thing, rather than cheap Chinese copy!