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Engine and Drive Train Parts

AJS / Matchless alloy barrel

AMC Heavyweight Single Barrel

The footprint is patterned on the later crankcase design but with a little judicious use of a file can be shaped to suit the earlier cases.
An alloy barrel results in greater efficiency in cooling as well as looking rather more impressive than the standard iron part.
Bare casting £180


AJS / Matchless timing cover

Matchless Timing Cover

Sand-cast in LM25 aluminium.
This is to fit a forward-facing magneto, thus keeping the sparks away from the carburettor.
Supplied polished but without the 'winged M' being painted.
AJS covers also available.


BSA unit single decompression spacer

BSA Unit Single Decompression Plate

To place under the barrel to change the characteristics of your engines' power delivery.
Available in thickness' from 1mm to 15mm.

From £9.95

BSA unit single barrel adaptor

BSA Unit Single Barrel Adaptor Plate

This cast aluminium spacer makes it easier to fit a roller big-end to any unit single.
For a more homogeneous look with the barrel it has a cast-in fin.
We offer to helicoil your crankcases to accept 10mm studs should they be required.


BSA unit single gear selector plate

BSA Unit Single Gear Plate - Improved

Suits C15, B25, B40, B44, B50.
A common problem with these engines, especially during the heat of a race, is the poor gear change.
Our solution has been to re-design the selector channels and indexing to give a more positive gear change.
Lazer-cut from stainless steel, this is a straight swap for the original (inferior) item

Triumph TR5 Trophy Inner Chaincase front

A new 'horeshoe' chaincase

Complete with oil seal and retainer

2 available at this time


Triumph unit twin gear selector plate

BSA Unit Single Gear Plate - Improved

An improvement on the original in that the grooves do not open out under duress.
Lazer-cut from 5mm stainless steel, this item requires the gearbox casing to be opened out slightly; achievable through use of a file.


alloy points cover

Alloy Points Cover

We have cast these covers with a little more depth than standard in order that they will suit BSA and Triumph twin engines and also to suit electronic ignition.


BSA bantam 175cc cylinder spacer

BSA Bantam Cylinder Spacer

By placing different thickness' of spacer under the barrel the port timing is changed helping you experiment with different power characteristics.
Available in thickness' from 1mm

From £9.50

BSA bantam 175cc head gasket

BSA Bantam 175cc Head Gasket

Head gasket available in copper or aluminium.
Available in thickness' from 0.8mm.

From £5.50

BSA bantam primary chain tensioner

BSA Bantam Primary Chain Tensioner

To optimise gearing for trials work various size engine sprockets are used often resulting in slack in the primary chain.
The chain tensioner locates on the two lugs to the rear of the engine sprocket.
On engine types Dl to D7 the pillar bolts allow the outer cover to be fitted using two short fixing screws.