No matter what I do top speed stays constant.

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Jayraye39 said:
My intake port is 43mm from top of jug by 12mm top and bottom of port by 22mm wide. can improvement be made here aswell
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I'm curious why at 43-45 mph top speed,which is more than most ever get from their engine, you are fussing about getting more speed from a poorly built engine. if you want more power than you already have I suggest you invest in an actual motorcycle with a bigger better built engine and totally legal on the street.
 
DAMIEN1307 said:
You better reconsider that fuel/oil ratio if your running this motor like that...No less oil than a 32:1 ratio unless you want to burn up your motor in quick order.


I would definitely be questioning that GPS speedo if it is reporting that as your speed.
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oil to fuel ratio was at more of a 60 or 65:1 ratio but that was bogging down the engine and spitting alot of oil out the exhaust. I reduced it slowly till I was getting the best mix to power I believe I can get. I'm not aiming to melt the piston as I managed to basically do that with the 49cc engine and I only achieved 58mph with that. also is why I reduced the racing fuel mix to 2oz per tank. I'm still able to crank a top speed of 61-64mph depending on wind shear. I also don't run it flat out all the time. that was my experimentation to see what I could manage to squeeze out of it. especially considering 80cc is actually at best maybe 65 or 70cc I believe I got more than I should've out of that engine. I baby it now cuz I had to replace the piston after that top speed run. the piston skirt showed char damage and a little thermal meltdown.
 
Oh, and "race fuel additive" or Octane booster, or whatever was added to the fuel. It won't make more power. Higher octane =/= more power. With unleaded fuel, Higher octane = longer hydrocarbon chains = more covalent bonds to break = more input energy needed to ignite and a longer time span to break all of the bonds in that chain (slower) = can result in a loss of efficiency and thus power if too high of an octane is used.

I said what I said. Come at me bro(s), rebel for life.
 
"Racing fuel"... Do you mean high octane gasoline that has an oxidizer (like nitro propane) added by the maker that's intended for true race engines and requires a richer fuel:air ratio than "normal" high octane gas? That stuff does increase power, if mixture is enriched and destroys engines if mixture isn't enriched.
 
SirLurksAlot said:
"Racing fuel"... Do you mean high octane gasoline that has an oxidizer (like nitro propane) added by the maker that's intended for true race engines and requires a richer fuel:air ratio than "normal" high octane gas? That stuff does increase power, if mixture is enriched and destroys engines if mixture isn't enriched.
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We have in the forums one member that is quite expert in the use of nitro propane in his bike builds, @Karl Snarl just look up some of his posts on nitro propane.

motoredbikes.com

Search results for query: nitropropane

motoredbikes.com motoredbikes.com
 
shdwolff said:
I'm curious why at 43-45 mph top speed,which is more than most ever get from their engine, you are fussing about getting more speed from a poorly built engine. if you want more power than you already have I suggest you invest in an actual motorcycle with a bigger better built engine and totally legal on the strstreet
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Because that is the beauty of this hobby. seeing how far you can take a cheap china motor that is intended to go 30mph. its a true test to your personal innovation and skills. its not the speed im after its the personal satisfaction and bragging rights
 
shdwolff said:
oil to fuel ratio was at more of a 60 or 65:1 ratio but that was bogging down the engine and spitting alot of oil out the exhaust. I reduced it slowly till I was getting the best mix to power I believe I can get. I'm not aiming to melt the piston as I managed to basically do that with the 49cc engine and I only achieved 58mph with that. also is why I reduced the racing fuel mix to 2oz per tank. I'm still able to crank a top speed of 61-64mph depending on wind shear. I also don't run it flat out all the time. that was my experimentation to see what I could manage to squeeze out of it. especially considering 80cc is actually at best maybe 65 or 70cc I believe I got more than I should've out of that engine. I baby it now cuz I had to replace the piston after that top speed run. the piston skirt showed char damage and a little thermal meltdown.
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So without the special racing fuel you're still doing 61-64 mpm; which means your engine is doing 11,641-12,213 rpm. Around what engines with top mods do. You've already melted down a 49cc piston at 11,068 rpm; because you said the oil mixture was to low.

It'd be interesting to see the results, if you invested in an actual speedometer and tachometer. If you found the Holy Grail of speed tuning an engine by all means educate us. Put specs out on exactly what you did. This is a sharing forum. We don't hoard secrets here, just so we can brag.
 
Sidewinder Jerry said:
So without the special racing fuel you're still doing 61-64 mpm; which means your engine is doing 11,641-12,213 rpm. Around what engines with top mods do. You've already melted down a 49cc piston at 11,068 rpm; because you said the oil mixture was to low.

It'd be interesting to see the results, if you invested in an actual speedometer and tachometer. If you found the Holy Grail of speed tuning an engine by all means educate us. Put specs out on exactly what you did. This is a sharing forum. We don't horde secrets here just so we can brag.
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LOL.


View: https://www.youtube.com/watch?v=bT8CRi9k4bo
 

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