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- Oct 17, 2008
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Ah, apologies
You're right. 2 Strokes can develop a lot of power but are extremely 'peaky'. My Karting engine won't pull anything if it drops to about 12,000rpm. A rotary valve 125 Rotax I had was worse, if you dropped 1500rpm below the power band it was literally like someone had turned the engine off. I know Suzuki in the 70's developed a hugely powerful GP engine, which was so peaky it required a 15 speed gearbox!
The trouble is with 2 stokes is you are essentially limited on inlet and exhaust timing by the piston which severly restricts 'broadening' up the performance of it. Also because the fuel is 'oiled', it;s denser meaning you have slower combustion flow. 4 strokes are a lot more forgiving you are right, but they have also in the last 10 years been developed a lot more than 2 strokes with electronic control.
You're right. 2 Strokes can develop a lot of power but are extremely 'peaky'. My Karting engine won't pull anything if it drops to about 12,000rpm. A rotary valve 125 Rotax I had was worse, if you dropped 1500rpm below the power band it was literally like someone had turned the engine off. I know Suzuki in the 70's developed a hugely powerful GP engine, which was so peaky it required a 15 speed gearbox!
The trouble is with 2 stokes is you are essentially limited on inlet and exhaust timing by the piston which severly restricts 'broadening' up the performance of it. Also because the fuel is 'oiled', it;s denser meaning you have slower combustion flow. 4 strokes are a lot more forgiving you are right, but they have also in the last 10 years been developed a lot more than 2 strokes with electronic control.