Definition of four-stroke in English:



  • 1Denoting an internal combustion engine having a cycle of four strokes (intake, compression, combustion, and exhaust).

    • ‘In four-stroke engines, one of the strokes is called the compression stroke.’
    • ‘Because a four-stroke engine burns straight unleaded, as opposed to the typical two-stroke's oil-and-gas mix, it's not only less polluting, but sounds more like a Lexus than a chainsaw.’
    • ‘The new model, designed exclusively for India, is powered by a 102 cc air-cooled, four-stroke engine with automatic transmission.’
    • ‘Most smaller gas powered four-stroke engines tend to run a 30 weight oil.’
    • ‘This was replaced in 1956 by a bigger four-stroke engine offering 297 cubic centimetres of raw power.’
    • ‘We moved from Stumps to Flemming's Bay, a trip of about five miles, which took less than ten minutes due to Mike having a ninety-horse power, four-stroke engine.’
    • ‘Its 25 cc, single-cylinder, four-stroke engine can power the aircraft at a cruise speed of between 70-90 kph for 8-10 hours.’
    • ‘Unlike two-stroke engines that have simple openings or ports for intake and exhaust, four-stroke engines have intake and exhaust valves at each cylinder head.’
    • ‘The latest API code is CI - 4 for the tops in performance for four-stroke diesel engines.’
    • ‘Buy one with a four-stroke engine - they emit one-tenth of the pollutants a two-stroke engine emits - and keep it maintained.’
    • ‘The first display showed the insides of a four-stroke engine, clutch assembly, gearbox, propeller shaft and differential gear box.’
    • ‘The four-stroke engine shows the cross-section of an engine complete with all functions such as fuel intake, ignition, piston compression, exhaust, and so on.’
    • ‘Almost all cars currently use what is called a four-stroke combustion cycle to convert gasoline into motion.’
    • ‘The combustion chamber of a four-stroke engine is designed to induce turbulence through the addition of ‘squish’ areas in which the top of the piston is the mirror image of a corresponding area of the cylinder head.’
    • ‘Power plants for this class of racing are four-stroke engines with a capacity limit of 1 litre with any number of cylinders in any configuration.’
    • ‘The noise was not appreciably less - perhaps 20 percent - when encountering groups of the newer, four-stroke engine sleds.’
    • ‘Things just got a little easier with Garelick's motor bracket for four-stroke motors.’
    • ‘The two-stroke cylinder head of the 100 cc TVS bike that was converted has been replaced by a new cylinder head, which suits only four-stroke engines.’
    • ‘The Max uses the 498 cc Rotax single cylinder four-stroke engine and Bombardier's Visco-lok traction system.’
    • ‘Each of the four major snowmobile manufacturers is producing one or more new models equipped with cleaner, four-stroke engines for 2003.’
    1. 1.1 Denoting a vehicle having a four-stroke engine.
      • ‘It has brought along Eterno, a tough sleek, four-stroke 150-cc scooter with a never-before-seen side-mounted engine designed exclusively for the rough and tough Indian conditions.’
      • ‘Two-wheeler maker TVS Motor Company has said it plans to replace two-stroke motorcycle ‘Max’ with a four-stroke entry-level motorcycle within six months to arrest the erosion in sales.’
      • ‘If achieved, this expedition will ensure the entry of the team - riding Fiero FX 150 cc four-stroke power bikes - in the Guinness Book of World Records.’
      • ‘The race was split into four categories 50 cc, four-stroke motorcycles up to 180 cc, novice riders on two-stroke bikes and 100 to 135 cc for the experienced.’
      • ‘While these hogged market mindspace, other local products like the 93 cc Byk from Bajaj or the 110 cc four-stroke Freedom bike from LML also carved out a niche in the pie.’
      • ‘The premier series has adopted four-stroke 990 cc bikes similar to, but much more advanced than, those in Superbikes, and many of the leading WSB teams and riders have abandoned the series for MotoGP.’
      • ‘Two-stroke motorcycles should pay more pollution tax than four-stroke motorcycles and Euro2 compliant cars should pay no taxes at all.’


  • A four-stroke engine or vehicle.

    • ‘I've just bought a Honda four-stroke, the Rolls Royce of mowers.’
    • ‘On the other hand, four-strokes are generally suited to applications appropriate to the lower horsepower range.’
    • ‘It weighs just slightly more than a comparable two stroke, a major break-through because just a few years ago, marine techies said four-strokes were unlikely to ever go higher than 100 hp.’