Found the old spec sheet from 15 yeaes ago. Some museum pieces when it comes to modern day tuning
Class 2 – 250 cc Motorcycle Racing
Frame 1970 GP 125
Lengthened by 4 inches
Steering angle altered to 55 degrees
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
Suspension
Front forks stiffened with 3 inch spacers and shortened springs
Rear shocker replaced with solid bar and lowered to 275 mm
Wheels
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
Controls
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
Tyres
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
Engine
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 a72 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 eight plate type using CLW 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.
1 by
100 MPH LAMBRETTA CLUB, on Flickr
042 by
100 MPH LAMBRETTA CLUB, on Flickr