Buggies Gone Wild Golf Cart Forum - View Single Post

sho305 · 05-10-2011, 10:48 AM

Its all about the diameter of a circle, if you put a small and large circle together. Lets say you have a saucer centered on a big plate, its 12" around (circumference) the saucer a 30 around (the edge) of the plate. If you turn the plate 1/4 revolution (90 degrees like my lever approximately) then the saucer (hooked to your pedal) turned 1/4 that or 3" and the plate (hooked to your carb) turned 1/4 so 7.5", the ratio is 12:30, or 6:15, or 3:5 to simplify. Sure you don't get that exactly because your cable or rod is not turning with the circle (unless you use a cam/pulley to hold the cable), but in about 90 degrees it can be close, just like your tie rod ends work on the spindle that swings in part of a circle.

What you would be doing here is cutting a pizza in four pieces (quarters) and then measuring the width of the crust, that is how far it moves in quarter turn (with a rod or no cam). Then you have to make the circle (pizza) the size you need, and then use a lever because that would be a waste of good pizza lol.

The easy way to do it is with paper and a rule. If you know how far your throttle cable travels and how far your carb needs to go, you know the ratio you need to match them up. Don't forget a little pedal play in there. Cut out a lever out of paper and hold the pivot point on the paper, then swing it and measure where you need to get your pedal travel mounted on it. Then go out more until you get the travel you need for the carb, at the same rotation as the pedal. Its better to mount it up so the lever is more angled to the cable at idle and closer to 90 at WOT. That gives you throttle tip in you want the WOT part to move faster. It will move slower the closer the lever gets to pointing up the cable, where it stops moving.

You can make a cam, but I don't recall there being much room at the pedal. You could use a garage door or patio sliding door pulley(s) for that just off the top of my head. If you make it on/around the engine then yeah you need two cables or a cable and a rod like I did it. The rod of course has to be inline with the carb mine is in same place the governor rod was before I removed it. If you found the two right sizes you could just shoot a bolt through the pulleys to make them turn as one. Still have to make the cable hook to them of course, and that is why levers are easier.

05-10-2011, 10:48 AM	#5
sho305 Vegas modded 420 Join Date: Jun 2009 Location: West MI Posts: 15,443	Re: Throttle linkage Its all about the diameter of a circle, if you put a small and large circle together. Lets say you have a saucer centered on a big plate, its 12" around (circumference) the saucer a 30 around (the edge) of the plate. If you turn the plate 1/4 revolution (90 degrees like my lever approximately) then the saucer (hooked to your pedal) turned 1/4 that or 3" and the plate (hooked to your carb) turned 1/4 so 7.5", the ratio is 12:30, or 6:15, or 3:5 to simplify. Sure you don't get that exactly because your cable or rod is not turning with the circle (unless you use a cam/pulley to hold the cable), but in about 90 degrees it can be close, just like your tie rod ends work on the spindle that swings in part of a circle. What you would be doing here is cutting a pizza in four pieces (quarters) and then measuring the width of the crust, that is how far it moves in quarter turn (with a rod or no cam). Then you have to make the circle (pizza) the size you need, and then use a lever because that would be a waste of good pizza lol. The easy way to do it is with paper and a rule. If you know how far your throttle cable travels and how far your carb needs to go, you know the ratio you need to match them up. Don't forget a little pedal play in there. Cut out a lever out of paper and hold the pivot point on the paper, then swing it and measure where you need to get your pedal travel mounted on it. Then go out more until you get the travel you need for the carb, at the same rotation as the pedal. Its better to mount it up so the lever is more angled to the cable at idle and closer to 90 at WOT. That gives you throttle tip in you want the WOT part to move faster. It will move slower the closer the lever gets to pointing up the cable, where it stops moving. You can make a cam, but I don't recall there being much room at the pedal. You could use a garage door or patio sliding door pulley(s) for that just off the top of my head. If you make it on/around the engine then yeah you need two cables or a cable and a rod like I did it. The rod of course has to be inline with the carb mine is in same place the governor rod was before I removed it. If you found the two right sizes you could just shoot a bolt through the pulleys to make them turn as one. Still have to make the cable hook to them of course, and that is why levers are easier.