a photo
For starters, we ask: what is the difference between a 2-stroke engine and a 4-stroke engine? Unassumingly, we’ll be indignant: “Yes, everyone - it’s the same as comparing a tomato with a giraffe”. And what about the invention of St. Petersburg Vladimir Pavlovich Kopeikin: imagine, he made a 4-stroke engine out of … 2-stroke?
Was it worth bothering and arranging a 2-step “genetic” transformation? The question is meaningless - sooner or later, the transformation was to happen, because Vladimir Pavlovich is an inventor. No one before him tried to build anything like this? All the better!
He built his first 4-stroke back in 1962. He was inspired by a motor from a photograph of the English motorcycle AJS, beloved Kopeykin “classics”. The engine from Izh-56, which at that time was a very perfect machine, was taken as a basis. He made a new cylinder, head, camshaft. Completely changed the lubrication system: installed an oil pump in the crankcase, which rotates from the same chain that goes to the camshaft. He brought the grease to the crankshaft bearings (they are lubricated under pressure) and into the cylinder head to the gas distribution system. Two valves and a camshaft located at the top, the drive - a chain from the crankshaft. I milled a new connecting rod and installed the lower head bearing rollers with an increased diameter (instead of 4x6 - 5x6), I made a cage myself. The stroke of the piston remained the same as on the Izh - 85 mm. Due to the self-made piston, the engine capacity increased to 450 “cubes” (I almost reached the “classic” - “five hundred”, like in AJS). The motorcycle turned out to be compact, reliable, easy to maintain, could ride on low-octane gasoline, starting from the 56th And this is already in 1962!
And what about our motor industry? Only in the 80s, the Izhmash plant engaged in the introduction of a licensed 4-stroke engine based on the Yamaha XT550. But something went wrong there …
