This very useful little item is a 'Top Hat' Ferrule - is to fit original Doherty and other similar throttle twistgrips, which are not threaded at their cable end - and if you are using a throttle cable which has its threaded adjuster in the middle of the cable, not on the twistgrip end - therefore this 'Top Hat' ferrule will stop the cable sliding through the twistgrip hole. 

Background to this item:

We offer both original Doherty throttle twistgrips (Item 0942) and a cheaper offshore version.  Many people (myself included) still like to fit an original branded product if available - for originality sake.  However - the Doherty type twistgrip does not have a threaded end and adjuster fitted - instead it relies on two types of throttle cable fitting:

- A throttle cable that has the adjuster at the throttle twistgrip end, and a nut on the adjuster - then when the cable is fitted, it is the nut that stops the cable from dropping through the twistgrip cable hole

- OR:  if you have a throttle cable with the adjuster mid-cable  . . . and the end of the outer throttle cable is just the normal cable ferrule (normally 0.220"/5.5mm diameter or thereabouts on most old British Bike throttle cables) - then it would normally be necessary to fit a 'Top Hat' ferrule, which slips over the end of the inner cable before fitting it to the twistgrip - and that slides into the end of the Twistgrip, holding the cable outer captive, stopping it from sliding through.

This style of Top Hat used to be available many years ago - I remember seeing them myself at autojumbles and used to have a couple in my cable tin . . . but when a customer pointed this out to me some months ago (when purchasing a Doherty twistgrip) - I could no longer find a manufacturer or supplier of them.

So - we have now manufactured this useful little ferrule ourselves  - they are CNC manufactured from stainless steel - and are also mill/slotted, so they can be slid over the inner cable, without having to remove the bullet at the end of the cable.

Note:  These only need to be used if your throttle twistgrip does not have a threaded adjuster already fitted (i.e - our similar offshore twistgrips are threaded and do have an adjuster

The dimensions are as follows (in case fitting to an original twistgrip or other type of twistgrip or similar):

- Diameter of Top Hat - where it slides into Twistgrip hole: 0.306"/7.8mm

-  Receptor hole for receiving throttle cable ferrule: 0.223"/5.7mm

- Slot width, for sliding throttle cable 'inner' wire through: 0.081"/2.00mm

Please satisfy yourself this is satisfactory for your purposes - and follow all normal safety practices when fitting throttle cables

CNC manufactured by us in stainless steel.  Price is each

Sorry not cheap - a suprising amount of machining (including milling) to make this tiny item!  However we discount this item to £4 if bought at the same time as a Doherty twistgrip from us (Item 0942)

This is a reproduction of the original 180 Degree banjo that was fitted to Amal TT, RN and GP alloy froat chambers from the late 1930's onwards.  This 180 Degree type was most commonly fitted to Norton SOHC (and Manx Norton) carburettors - and is much rarer to find than the '90 degree' type more commonnly fitted to other motorcycle marques using the Amal competition carburettors through to the early 1960s.  

Price is per each banjo, but includes the two red fibre washers fitted either side of these banjos - from a high quality manufacturer.

This type of competition banjo were fitted to the Amal TT, RN and GP carburettor float chambers that were used from the late 1930's onwards.  I expect most customers looking at this listing will be familiar with their own carburettor - but please note that earlier pre-War TT carbs were often fitted with a brass floatchamber, which used a smaller bore banjo - if you have that earlier type of float chamber - then sorry, this banjo will not fit.  Email us for details and dimensions on sales@racingvincent.co.uk if you are not sure and want to check.

This style of alloy cast banjo were originally produced in twin inlet 180 degree type (most often used on genuine SOHC Norton machines), 90 degree twin outlet (commonly used on many marques through the late 1950s), and also in single inlet guise - commonly used on the main carburettor body, when using a remote float chamber.  

This 'twin inlet' 180 degree type is possibly the hardest to find today, and although it can be fitted to any marqure using the floatchamber shown in the photo, and the larger/later type 302 Floatchamber . . . it was specifically the type most normally fitted to competition Norton carbs from the late 1930's through to the mid 1950's.

These banjos are cast in heat treated aluminium, using an original 180 degree period casting as a pattern (taken from an original Amal RN Manx Norton carburettor), and then CNC machined to the original bore dimensions and 1/4" BSP pipe fittings.  Each banjo is supplied with two high quality red fibre wahers of the correct diameter for these banjos.

Please note:  The original Amal banjo shown in the photo was itself not of the highest quality - in that the casting lines were quite visible and had been linished as part of the original manufacturing process.  Added to this, the original casting was machined fractionally off centre.  We had these castings cast from a silicone pattern taken from this original banjo (rather than a purpose manufactured 'boxed pattern', which would have been prohibitively expensive).  Therefore, I would be truthful enough to say that the quality of these castings are not of the highest quality, and although each casting has been linished (as the original was) before machining - their finish is not quite as good as we would have liked, and some may be machined slightly off centre as well - as per the photograph.  However, rest assured - each banjo is checked after machining to ensure the full width of fibre washer makes contact ... . and as most are aware, this is now a very difficult item to find - we only have very limited numbers of them (and we have barely covered our manufacturing and CNC setup costs!)

This is the red fibre washer that fits between the main Jet Holder and the float chamber (two being used at this point) on original Amal TT, RN and GP competition carburettors.

The same washer is also used on the main banjo's used from 1940's onwards and fitted to TT's, RN's and GP's as well as Remote float chambers (again 2 fitted per banjo fitting. 

These washers come  from a a high quality washer manufacturer and are of a higher quality than any other red fibre washer we have found - they cost much more than other manufacturers (approxiimately 3 times as much as others we have found of similar dimensions), but as the old saying goes - 'you get what you pay for!' . . . I use them on all my own Amal comp carb rebuilds,  

Slightly cheaper than Item 0165 when bought as a pack of six.

This is the red fibre washer that fits between the main Jet Holder and the float chamber (two being used at this point). The same washer is also used on the main banjo's used from 1940's onwards and fitted to TT's, RN's and GP's as well as Remote float chambers (again 2 fitted per banjo fitting.

We get these washers from a a high quality washer manufacturer specifically for this purpose and are very durable - hence the higher price than those sold in the complete washer sets (Item0164). I always use these washer myself when restoring a carburettor - and they have nice crisp edges that also look correct.

Price is per pair of washers

This is the Banjo Nut as fitted to original TT, RN and GP competition carburettors that were fitted with the large banjo type floatchamber - either bottom feed alloy type or top feed Type 302 floatchambers.

These banjo nuts have include the all important lockwire hole and are nicely finished in satin nickel plate.  Price is each.

Most Manx Nortons and postwar International Norton's were fitted with the larger banjo floatchambers that required this type of nut. 

If you have a Type 302 'Remote' mounted floatchamber, whe also sell the banjo nut that allows for the remote mounting - see Item 0292.

We also sell a high quality red fibre washer to fit these banjo nuts (two normally required - one above and one below the banjo) - which is item 0165

These are genuine (old stock) Amal Racing Type main jets - of the type originally supplied for Amal TT/RN/GP racing carburettors.

They are easily identifiable as being the original racing Amal TT/RN type - because the hex part of the jet is uninterupted along its entire length, while the more common later Amal main jets (fitted to all road and competition carbs) had an indented section 2/3 along the jet, which is where the size is stamped.

On these earlier racing jets the main jet size is stamped in slightly larger numerals along one edge of the hex, as can be seen in the accompanyning photographs.  Many of these jets are in the much larger sizes only fitted to racing carbs.  It should be noted, that the later indented type can be fitted to Amal TT, RN and GP carburettors (and jet size should be the same calibration for both) - but out of preference, many people like to fit these original racing jets if available 

As well as the original TT/RN (straight hex) jets, in the same collection were a number of original Amal main jets of the later 'indented hex' design, which were manufactured later for all carb types - including Monobloc and Concentric.  These jets are original Amal (I would between 30 - 50 years old), but similar to the type available new today which we also sell - Item 0153.  Again, the table below shows this 3rd type of original Amal jet (0901_3) - state which size when ordering. All jets of this type are interchangeable with the original 'straight hex' racing type, and there are actually some very small sizes - going down to a very small 050 size.

Price is for a single jet, please state which size you require in the comment section when placing order. 

We have sub-divided the jets into 3 types:

0901_1 : Original RN/TT 'Straight hex' type: Size from 280 - 640 (mainly petrol)

0901_2 : Original RN/TT 'Straight hex' type: Size from 650 - 1900 (mainly alchohol/methanol. 

0901_3 : Original later Amal 'Indented hex' type: Various Sizes - see table below.  

The larger TT/RN jets are slightly more expensive due to their rarity.  

A Table of all available jet sizes is shown at the bottom of this listing (but apologies if not not kept fully up to date as jets sell).

Background on these jets:  A short time ago I was fortunate to be offered this large collection of original main jets from an ex-racer who was clearly serious about setting his carburettors up correctly (I know he raced both Manx and Gold Star models) - as the collecton was kept in a large box, split into sub-sections by jet size, ranging from approximately 280 up to the largest methanol/alchohol sizes.

All jets are in good original, unmolested condition - and some have clearly never been fitted (i.e. New Old Stock), because they still have the original wire/lead spot they were supplied with when new.  

If you are setting up a TT, RN or GP carburettor it is always a good idea to keep a selection of jets of various sizes - so that you can vary the jetting, to get the ideal jet for your state of tune/fuel.  Doing any form of engine tuning, changing fuel (or even ambient track temperature on a finely tuned engine) can make a difference.  If you are not sure how to tune your Amal racing carburettor for the correct Main Jet/Needle Jet/Slide/Needle settings, then in our Facsimile/Catalog section we offer a facsimile that includes original Amal information how to do this.

As a general rule of thumb - I have found that most competition bikes using Amal TT/RN on petrol tend to use main jet sizes up to a @ 650 main jet (dependent on cc/state of tune), while those bikes running on methanol or alchohol use much bigger jets from 550 all the way up to a (massive) 1900.  These original larger jets are now very uncommon to find - and once these are gone I doubt I will be offering any more!

Table of Jet Sizes Available:

Useful little box key spanner for fitting and unfitting main jets on most Amal carbs that used the standard type Amal Main Jets (as shown in photo).

Nice quality and very useful to keep in your toolkit . . . saves trying to find a spanner to fit!!