Rules

   General Machine Rules

All machines to be of British manufacture.
The machine classes are:-
 Class A - pre unit springers over 347cc, Class B - pre unit tele fork rigid over 347cc, Class C - pre unit girder fork over 347cc, Class D - unit to 246cc, Class E - unit over 246cc, Class F - two stroke to 1970, Class G - twin cylinder over 347cc, Class H - vintage two stroke, Class J - pre unit rigid or springer under 347cc, Class K - Clubmen on any machine riding an eased routeClass S - Specials, machines not fully complying to the machine class rules.

In line with the club's aim of retaining the spirit of the sport as it was in the 60's, machines must retain a period appearance but some alterations are allowed to improve reliability, performance and safety.

Main Frame LoopMain frame loop to be retained as original but may be strengthened. Repiica frames are accepted but must be recognisable as the original.Petrol and oil tanks can be repositioned.Any colour change allowed.

Rear Sub Frame And Swinging ArmRear sub frame can be altered in height and width but the shock absorber mounting point must retain the original position so as not to change the angle of the shock absorbers.The swinging arm can be altered in width and length but the shock absorber mounting point must retain the original position so as not to change the angle of the shock absorber.

Front ForksAll machines apart from class F (two strokes to 1970) must be fitted with forks which appear externally to be of pre-65 British manufacture. Telescopic forks must be fitted with rubber gaiters or metal shrouds. R.E.H., M.P and Ceriani are not allowed.Class F machines can be fitted with forks of original appearance or pre-70 R.E.H, MP or Ceriani forks where originally fitted.

YokesOnly pre-65 British manufactured or replica yokes can be used.

WheelsSize of wheels not to exceed 21" front and 19" rear
 
HubsHubs must be of pre-65 British manufacture or replica, period Rickman, R.E.H. etc allowed

Rims And SpokesAny make or origin of rims and spokes can be usedTubeless rims to be fitted with correct size inner tubes.Inner tubes of correct size to be fitted, (tube valve only to protrude through Rim)
 
TyresAny make of tyre can be used, but tread pattern must be of standard trials typeTyre cutting is not allowed

Tyre PressureRiders choice

Rear Shock absorbersAny rear shock absorber, other than separate oil/gas reservoir type, can be used.Length of rear units to be within the range of good sense and reason.

Fuel Tank And Seat UnitAny type of tank and seat unit can be used.

Engine And GearboxEngine and gearbox must be original or of the same type manufactured for the appropriate class.No hydraulic Clutch or Clutch Controls to be fitted.

CarburettorsMust be of British manufacture and the type originally fitted to engine.ALLOWED ALTERATIONS - Amal mkI. concentric allowed.
  - Tiger cubs may be fitted with non-British manufactured carburettors.

IgnitionAny ignition system can be used.

BrakesFront and rear brakes must be fitted and working.Only hub brakes may be used (no disc brakes).Any linkage for rear brake may be used i.e. rod or cable.Brake shoes may be fitted with any type or make of lining.No hydraulic Brakes or Brake Controls to be fitted.

Exhaust And SilencersAny exhaust system may be used but a reasonable air gap between exhaust pipe and fuel supply is required.Silencers must be effective. If a machine is deemed to be too loud, entry may be denied.

  Particular Machine Rules
Classes A,B & C - Pre units over 347cc Frames must be originally designed for engines over 347cc

Class F - Two Stroke British two stroke machines manufactured from 1965 to 1970 are eligible to enter and compete in the F class. Two strokes originally fitted with leading link forks cannot be changed to telefork suspension units of any age.Greeves fitted with banana forks are accepted as pre 65.Pre 70 R.E.H., Ceriani or M.P. can be used on F class machines where originally fitted.Sprites fitted with B.S.A., Norton or A.M.C. forks are accepted as pre 65.Four speed Bantams are allowed in two strokes Class (F).Sprites,James etc may use leading link forks or telescopic forks -BSA, Norton,AMC etc.

Tiger CubsTiger Cubs are allowed to use carburettors other than of British manufacture.Tiger Cubs up to 250cc can enter and compete in the D class.

Class G - Twin cylinderpre unit or unit engines can be usedRoyal Enfield Crusader type frames can be used. 
  To clarify any point regarding Machine rules contact Barry Pickard on 01535 680203.

  Rules for Riders
Age LimitsThe minimum age for riders is 15. Riders under 18 must have the parental consent section of the entry form signed by a parent. There is no maximum age limit, our eldest regular rider is 79..

licencesCompetition licence, we are affiliated to the A.M.C.A. and the ACU. A competition licence is not required to enter our events.Driving licence - with the exception of the West Riding Trial, all our events are held on private land and therefore a driving licence is not required.

MembershipNon-members can ride in one trial as a guest. Any points scored as a guest will not count towards the championship.

BikesEach rider can only use one machine in an event, the machine must be for the rider's sole use during the event.

SafetySafety helmets must be worn at all times whilst riding at the venue.