Received some great information from Bernard, he is the owner of one of the Skoal Bandit XR70 bikes. Bernard thanks for this!
When Suzuki retired from the 500 GPs at the end of 83, the old square four (created in 73) was no more competitive against the Honda and Yamaha V4's. Therefore they continued to provide support to Heron in UK and Gallina in Italy with works engines and Suzuki alloy frames. In the UK the Heron team decided to invest in a new frame to reduce the weight and ordered 2 prototypes from Nigel Leaper in Cambridge. The first prototypes were "white" with aluminium sheets on honeycomb material from Ciba Geigy. Six other bikes were build after the prototypes. In 84 they used XR40 engines, in 85 XR45 with exhausts valves and in 86 the last square four, the XR70 with reed valves instead of disc valves. In 84 and 85 they used alloy swing arms and Suzuki forks but in the middle ot 86 they changed for a carbon swing arm and a White Power fork. The weight of the 86 bike was around 110 kgs and the maximum power was 148 HP due to the UK development especially in exhausts, heads and air-boxes. The problem was that the factory was not interested in carbon (too far away from the production road bikes) so at the beginning they were not helpful with the UK team but the results were better than the Gallina bikes so in 85 Heron got better engines and support. The carbon frame was too stiff, it was the most important problem because the bike was so light. The first pilot in 84 was Rob McElnea, In 85 Paul Lewis came in the team and McElnea left to Yamaha. In 86 Paul Lewis was still in the team with Niall MacKenzie and in the middle of the season Kevin Schwantz also got a bike. For the last race (The GP of San Marino at Misano) MacKenzie was in the first row. Kevin Schwantz won his first point in the 500cc class in Spa Francorchamps. At the end of 86, Suzuki announced their return as official team with the new XR71 V4. A batch of carbon bikes was sold at the end of 86 to Gerhard Vogt in Germany and 2 bikes with the XR70RV engine to the Frankonia team in Switzerland with Wolfgang von Muralt as pilot. They used the bikes for 2 years and at the end of 88 these bikes went to Germany also.
For pics of these bikes see
Carbonfiber framed Suzuki RG & RGV500 racers