Norton Interpol 2
The Interpol 2 (or P41) was produced from 1984 to 1989. It has an air-cooled twin rotor 588 cc (35.9 cu in) Wankel engine, which was a project inherited from BSA when the NVT groups were merged. Norton did not sell the Interpol 2 to the general public. Sales were restricted to fleet customers: civilian police forces, military police forces (particularly the Royal Air Force Police), and the RAC.
This should have been Norton's lifeline into a new era of manufacture, sales and profit. However, despite much testing and development with the police, this took longer than expected. In fact, this development work on the engine meant that Norton took out more patents on the engine than Wankel ever did.
The chassis was a pressed steel box section. To speed-up development, a number of Yamaha parts were used, notably forks and electrics. It is rumored that the very early prototypes even used a Moto-Guzzi seat and tank.
The big problems were excessive wear on the rotor tips, sticking rotor tips and plug fouling. This, in part, was due to the additives that were in the special oils that were being tried. Even ceramic rotors were tried. The solution was quite simple - use a very basic oil as it's a total-loss system, just like a two-stroke and to Moly coat the chambers. Problems with eratic tick-over were largely solved by just running on one cylinder until both were needed. However, they were known for their smooth running and instant power.
A racing version was produced which used some clever modifications to the engine to keep it cool. Its racing sucess would have been better if it had been allowed to compete in the 750cc class as Norton intended. It was a victim of its own sucess on the race circuit and the FIM decided to use a different method of calculating its capacity, thus rating it at 588cc.
A water-cooled version was developed, the P52, which became the Commander and sold to police and civilian markets.
Norton Interpol2 RAF police B935BFJ
Engine: Twin chamber rotary
Capacity: 588 cc / 35.9 cu in
Compression Ratio: 9.0:1
Cooling System: Air cooled
Induction: 2 x ~A38 mm CV SUH14
Ignition: Electronic CDI, 2 x 12V coils
Max Power: 63.4 kW / 85 hp @ 9000 rpm
Max Torque: 75.3 Nm / 7.69 kgf-m / 55.6 lb-ft @ 7000 rpm
Clutch: Progressive multi-plate
Transmission: 5 Speed
Final Drive: Enclosed Chain
Rake: 28 degrees
Trail: 127 mm / 5.0 in
Front Suspension: ~A38 mm Telescopic forks 130mm wheel travel.
Front Wheel Travel: 130 mm / 5.1 in
Rear Suspension: Twin Girling gas units, 3-way preload
Front Brakes: 2 x ~A265 mm discs
Rear Brakes: Single ~A265 mm disc
Front Tyre: 100/90-18
Rear Tyre: 110/80-18
Dry-Weight: 235 kg / 518 lbs
Fuel Capacity: 23 L / 6.1 US gal