Hello, As a former UK road racer from the 70's who used to race 250cc single cylinder 2 strokes could some one answer a few questions for me re AC kart engines as these really appeal to me. If using a conventional carb what would the main jet size be, timing BTDC, RPM, power band width. What would the ideal cylinder temperature be under race conditions. Are you bothered about crank balance. I think these engines look the dogs danglies.
@@malcrandall1309 the timing is 104" BTDC. RPM starts at 10,200 up to 16,000 depending on pipe. Cylinder temp at the head should be 350F. Exhaust temp no higher than 1,100F which is on the edge. Crank balance no issues. Our piston weight is the same as the Original Piston. Hope that answers your questions. Regarding the carb, the driver controls the mix and can lean it down or richen it up as he drives the kart. It's a pumper carb.
@@malcrandall1309 104" BTDC is in inches not metric . I use an indicator that screws into spark plug hole. ZERO The indicator when the piston is at TDC. Then when piston is at 104" BTDC your good to go. I don't run that much timing on gas, helps to keep temps down. Typically I will set a 56mm stroke engine on gas at .095" BTDC
@@speedpartsKomets Ah, Got it. So many people here on UA-cam are in the computer age which I'm not and use degrees. I did notice you used the inch symbol but thought that was indicating degrees. The .095" BTDC I fully understand. Just over 2.4 mm. Many thanks for your time.
Hello,
As a former UK road racer from the 70's who used to race 250cc single cylinder 2 strokes could some one answer a few questions for me re AC kart engines as these really appeal to me.
If using a conventional carb what would the main jet size be, timing BTDC, RPM, power band width. What would the ideal cylinder temperature be under race conditions. Are you bothered about crank balance.
I think these engines look the dogs danglies.
@@malcrandall1309 the timing is 104" BTDC. RPM starts at 10,200 up to 16,000 depending on pipe. Cylinder temp at the head should be 350F. Exhaust temp no higher than 1,100F which is on the edge. Crank balance no issues. Our piston weight is the same as the Original Piston. Hope that answers your questions. Regarding the carb, the driver controls the mix and can lean it down or richen it up as he drives the kart. It's a pumper carb.
@@speedpartsKomets Thanks for your kind speedy reply. Do you have a rough idea of what 104 deg would be in mm or inches. My minds working over time!
@@malcrandall1309 104" BTDC is in inches not metric . I use an indicator that screws into spark plug hole. ZERO The indicator when the piston is at TDC. Then when piston is at 104" BTDC your good to go. I don't run that much timing on gas, helps to keep temps down. Typically I will set a 56mm stroke engine on gas at .095" BTDC
@@speedpartsKomets Ah, Got it. So many people here on UA-cam are in the computer age which I'm not and use degrees. I did notice you used the inch symbol but thought that was indicating degrees. The .095" BTDC I fully understand. Just over 2.4 mm.
Many thanks for your time.