2-Smoke vs. 4-Stroke
by Yale Henry
(Beautiful British Columbia!)
I have read a lot of opinions about the two kinds of engines and being a motorcycle mechanic and an avid rider I of course have my own opinion.
2-strokes are lighter with less moving parts, although they lack low-end power. As soon as they gain rpm the power and torque just go up and up until you can barely hold on. The only maintenance issue with a 2-stroke is replacement rings and/or pistons, unless the person didn't mix the fuel right then there is a big problem. 2-strokes take more fuel sure, but with new technology coming out like DFI systems, 2-strokes will dominate 4-strokes in power and have a slightly higher fuel consumption.
4-strokes have a smoother powerband but, you beat the 2-stroke around the corner on the track but, OH WAIT!.. who's that passing you on the straight? The guy on the two stroke!
Many people think that maintenance is cheaper on a 4-stroke but the bill adds up over time. On avg. a 4-stroke will come in 4 or 5 times or more, for valve adjustments before the 2-stroke comes in for a ring or piston replacement. But eventually the 4-strokes rings have to be replaced, the valves and valve springs, timing chain replacement, it just gets more and more expensive whereas the 2-stroke has what?.. just rings and piston replacements. Do the math.
4-strokes have good low end power and a smooth powerband, so they are good for tricks, smooth riding and cornering.
2-strokes have excellent high rpm power, keep the rpm high and you have all the power you need in any situation, cornering, acceleration etc...
Btw, when a 4-stroke is poorly maintained or the rpm is too high for too long, the cost for repairs goes through the roof! They take longer to repair and they are harder to fix, so labor costs go up. Basically it would just be easier to buy a brand new 2-stroke which is a fraction of the cost for new parts and engine rebuilds.