can anyone advise me on the montesa pre mix ratio,i have been running on 100ml of oil per 5 litres of petrol but bike does not respond well to full throttle.having just obtained a manual of ebay for my 315 i read that i should be running a ratio of 80 to 1 which i understand to be in the region of 75ml per 5 litres of petrol,would be grateful for any advise as i do not want to seize the engine.