All content © National Twinshock Trial Championship 2015

This class will be open to all air cooled monoshock and any air cooled monoshock trials bike that has been converted to a twinshock.


Eligibility – the motorcycles should maintain the original silhouette as the date of manufacture.

Acceptable modifications are;

The option to run tubeless tyres, to make minor modifications to the frame, and a choice of carburettors


Unacceptable modifications;

Disc brake conversions unless already fitted.

Fork stanchions must not exceed 36 mm



Class 1

This class is open to all Spanish manufactured twinshock trials bikes for any year.

Standard pre ‘78 twinshocks are  eligible in this class. Suitable bikes, Beamish Suzuki, Yamaha TY175 (not Majesty)and Honda TL series, these bikes must be completely standard as per original manufacture otherwise enter class 3.

The object of this class is to keep the cost of competing to a minimum but maintaining a highly competitive series.

Eligibility – the motorcycles should maintain the original silhouette as the date of manufacture.

Acceptable modifications are;

The option to run tubeless tyres, to make minor modifications to the frame, and a choice of carburettors, cycle parts can be changed as long as they are from the same period and from other Spanish motorcycles. Shock absorber and suspension movement should be similar to the original specification. Steering head angle can be moved and the swinging arm lengthened. The position of the footrest can also be moved.


Unacceptable modifications;
Disc brake conversions
Fork stanchions must not exceed 35 mm

Class 2

This is open to all twinshock trials bikes  and highly modified Spanish twinshocks.


Whilst our intention is to try to keep to as original machine silhouette as possible more modifications will be allowed.


Acceptable modifications are;

The option to run tubeless tyres, to make minor modifications to the frame, and a choice of carburettors, cycle parts can be changed as long as they are from the same period.


Unacceptable modifications;

Modified monoshock trials bikes converted to twinshocks, air cooled monoshock engines, and disc brake conversions.

Fork stanchions must not exceed 36 mm

Note SWM jumbos fitted with the original 38mm forks are acceptable






Class 3 Observers

Observers are an integral part in the success of this series, in a show of thanks we are proposing a sponsored draw with prizes of £100, £50 and £25 at each round.


This class is open to British  bikes

Acceptable modifications

The option to run tubeless tyres, to make minor modifications to the frame and a choice of carburettors. Cycle parts can be changed as long they are from the same period


Class 4 Britshock Pre 72 Bikes