DetonatorTuning
Active Member
i had lots of experience with 2stroke dirt bikes and Yam. RZ350's on the street back in the day but have only been involved in the "micro" 50cc range engines for the past couple yrs.
i've been using a 46cc GP460 exclusively that makes 4.2 HP and 2.35 #'sFt. TRQ. and been surprized at how well this level of power will move a bike when coupled to an appropriate gear ratiio. this engine will move my bike 50mph at13500rpm using a ratio of 20.91:1
what intrigues me is the level of performance increases achieved thru various tuning practices within this displacement group.
an engine i'm interested in currently is 8% larger (49.something cc's), uses the same CR and makes 40% more HP, 60% more TRQ. and the peaks for both are only 500rpm apart rather than 3,000rpm for the GP460.
this engine should be able to move me 50mph @ 9000rpm using a 13.89:1 ratio, achievable in a single step, no jackshaft needed.
i know many are challenged and upset by this kind of speed being discussed and i only report them as reference for my target constant cruising speed of 40mph, because although i had good performance and economy from the GP460 at that speed, this new engine should be able to provide it while in a much less stressed operating condition.
end of ramble, please resume riding.
steve
i've been using a 46cc GP460 exclusively that makes 4.2 HP and 2.35 #'sFt. TRQ. and been surprized at how well this level of power will move a bike when coupled to an appropriate gear ratiio. this engine will move my bike 50mph at13500rpm using a ratio of 20.91:1
what intrigues me is the level of performance increases achieved thru various tuning practices within this displacement group.
an engine i'm interested in currently is 8% larger (49.something cc's), uses the same CR and makes 40% more HP, 60% more TRQ. and the peaks for both are only 500rpm apart rather than 3,000rpm for the GP460.
this engine should be able to move me 50mph @ 9000rpm using a 13.89:1 ratio, achievable in a single step, no jackshaft needed.
i know many are challenged and upset by this kind of speed being discussed and i only report them as reference for my target constant cruising speed of 40mph, because although i had good performance and economy from the GP460 at that speed, this new engine should be able to provide it while in a much less stressed operating condition.
end of ramble, please resume riding.
steve
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