Compression ratios and squish bands are interlinked. Stan explains the difference between them.
I have been thinking, how can I make an article on two-stroke compression ratios and squish bands interesting, but with TV offering 'Strictly Come Posing' and I'm a nobody get me out of here!' and watchirg Arsenal passing the ball across the back four for 90 minutes, squish bands all of a sudden look exciting
So, I am going to start with compression ratios. The compression ratio is the ratio between the volume of the cylinder and volume of the combustion chamber. And on most classic two-stroke read bikes there is a power increase to be had by increasing this ratio. There is always an optimum compression above which tine increase in heat negates the proposed increase in power, and as we are not dealing with race engines here it is wise to be conservative with increases in compression. Typically, small increases in compression will be beneficial throughout the rev-range and larger increases in compression will benefit performance at lower revs but be detrimental to power at higher revs. For example a motocross engine would run a higher compression than a road race engine if they were both running on the same fuel.
On a classic two-stroke I would rot recommend more than a 7:1 (7 to 1) compression ratic and yoi would need to use the best unleaded fuel with the highest octane ra:ing.
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