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Amal Carburettors Australia for Classic British Motorcycles

Amal Carburettors Australia

Amal Carburettors have been regular race winners since the earliest days of motorcycling-and they keep on winning, year in year out.

If your bike is fitted with one or more Amal carburettors and has seen a lot of mileage on the street, trail or dirt- you’ll find that refitting with an all-new Amal carburettor system will bring back some of that new motorcycle engine performance you first experienced your first time out of your dealers showroom.

Amal carburettors were originally made by Amal Ltd in Birmingham, England.  They are now made by Burlen Ltd in Salisbury, England.  Classic Bike Spares is an Australian distributor of genuine Amal carburettors and Amal spare parts.  Be aware that if Amal is not stamped on the part you are buying it is not a genuine Amal.

Installing Amal Carburetters

Amal carburettors can be damaged by careless installation to the engine. Use the following instructions to avoid distorting your carburettors.

The flange to which the carburettor is attached must be perfectly flat and clean. Remove all traces of old gaskets and gasket cement before installation. If possible remove manifolds with uneven surfaces and restore flatness using wet and dry paper over a flat surface, or fine grinding paste on a piece of glass. Heat reducing spacers should be similarly treated to ensure flatness. Bolting the carburettor to a distorted flange or uneven spacer increases the risk of carburettor body or flange distortion.

Always remove and replace the carburettor fully assembled, with the float chamber and mixing chamber lid, throttle cable and slide components installed. This ensures maximum rigidity of the assembly while it is being installed.

Tighten the mounting nuts carefully and evenly. Nuts and spring washers should be tightened until the spring washer is just flattened. Over-tightening the nuts will over-compress the flange gaskets at the flange extremities and may warp the flange, and in extreme cases the carburettor body, causing the throttle valve to stick.

Mk 1 carburettors are not designed to bolt tightly to the intake flange and may distort if overtightened. It is only necessary to compress the o-ring seal to ensure air tightness. When correctly tightened the carburettor flange and engine manifold should be no more than just touching. Nyloc nuts should always be used to mount Amal Mk 1 carburettors.

Where the thicker o-rings are used, on early Monoblocs and some Mk 1 carburettors, the nuts should be tightened until the clearance between the carburettor flange and the manifold surface is no less than 0.025 inches at all points.

Ensure that throttle and choke cables are able to open and shut freely when the petrol tank is replaced on the bike. Also make sure they are not affected by moving the handlebars from side to side.

How to choose the right Amal Carburettor for your classic motorcycle

Mk 1, Mk1.5 and Mk 2 Concentrics – Carburettor type number, followed by internal bore diameter, followed by the following specification number, according to adjuster screw handling and fuel type, for example:
928/300 is a Mk 1 900 series, with a 28mm bore, right hand adjustment, for a 4 stroke petrol engine.
1930/301 is a Mk 1.5 series with a 30mm bore, left hand adjustment, for a 4 stroke petrol with flange mounting.
2932/302 is a Mk 2 series with a 32mm bore, right hand adjustment, 2 stoke petrol with spigot mounting.
2934/303 is a Mk 2 series with a 34mm bore, left hand adjustment, 2 stoke petrol with spigot mounting.
2036/304 is a Mk 2 series with a 36mm bore, right hand adjustment, 4 stoke alcohol fueled with spigot mounting.

Smoothbore carburettor specifications end with a ‘T’ designation. The specification numbers for petrol are:
Right hand adjustment: /300 4 Stroke, /302 2 Stroke, /306 2 Stroke Powerjet, /310T 2 Stroke Smoothbore, /312T 4 Stroke Smoothbore
Left hand adjustment: /301 4 Stroke, /303 2 Stoke, /307 2 Stroke Powerjet, /311T 2 Stroke Smoothbore, /313 4 Stroke Smoothbore

The specification numbers for Alcohol are:
Right hand adjustment: /304 4 Stroke, /308 4 Stroke Smoothbore
Left hand adjustment: /305 4 Stroke, /309 4 Stroke Smoothbore

Monobloc Carburettors – Carburettor type number, for example 376 or 389, followed by size designation.
376 series – size designations are: 1516 for 15/16″ bore diameter, 1616 for 1″ bore diameter and 1716 for 1 1/16″ bore diameter.
389 series – size designations are: 3632 for 1 1/8″ bore diameter, 3732 for 1 1/16″ bore diameter.
Both series are only available in right hand adjuster form.  ‘Short’ float bowl versions (‘S’ designation) are available.

Pre-Monobloc Carburettors – Order by vehicle specification or build your own features.

Amal Carburettor Products Available in Australia