Bike Specification

  • Class 2 – 250 cc Motorcycle Racing
  • Frame 1970 GP 125
  • Lengthened by 4 inches
  • Steering angle altered to 55 degrees

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  • Forks lowered by 4 inches
  • Top shell removed replaced with tubular steel section lowered by 2 inches
  • Carbon fibre seat fairing from Aprillia 250 GP motorbike
  • Cut down carbon fibre leg shields and GP carbon fibre horn casting
  • NRG light weight front mudguard


  • Front forks stiffened with 3 inch spacers and shortened springs
  • Rear shocker replaced with solid bar and lowered to 275 mm


  • Front drum brake fully lightened, oil seals removed and using low friction bearings running in Teflon lubricant
  • Front rims are standard Lambretta split type
  • Rear rims are AF wide split type
  • Rear hub fully lightened Spanish type running with lightened brake shoes

Fuel tank

  • ¼ gallon cylindrical aluminium tank, rubber mounted to prevent fuel frothing and angle mounted for fast drain
  • Fuel tap ¼ inch fast flow methanol type using a one way quick release coupling


  • Short space ace bars mounted on LD clamp
  • Throttle, Honda motor cross type
  • Gear change, modified MB cast type
  • Front brake leaver, Amal light weight type
  • Back brake, Shimanno thumb operated paddle
  • Rev counter Scitsu 12,000 rpm dial type


  • Front wheel, 350- 10 Continental zippy 1 using up to 45 psi
  • Rear wheel, 110/80 - 10, 100/90-10 or 350 – 10 Continental zippy 1 using up to 35 psi


  • 1963 LI 150 casing
  • Crank mouth opened up to take aluminium Yamaha barrel, which has been extensively modified by MB Developments
  • 4 main transfers with two boost ports added by Ralph Saxilby
  • Piston ported induction using a 72 mm Wiseco Suzuki TS250 piston lightened by John Floyd
  • Six stud central plug cylinder head from billet aluminium, running a compression of 13: 1
  • GP crank with full padding using a Rotax conrod with a stroke of 60 mm
  • Carburettor is a Mikuni TMX 35
  • Fuel is Sunnoco MO2X rated at 114 octane
  • Ignition stator is a Motorplat internal rotor type set at 42 degrees before T.D.C with a 2.7 degree advancer box
  • Gearing is TV200 treated gear box running on 15/46 for the ¼ mile and 17/46 for the flying mile
  • Clutch is an MB Developments six plate type using Taffspeed extra strong springs
  • Chain is either an 80 or 81 link Regina extra and uses a light weight nylon tensioner

Weight of the bike fully fuelled is 138 lbs
Power output is estimated between 33 to 36 bhp at the rear wheel


Copyright © 2007 Fluid Media Ltd.