Miatav8,MstrASE,A&P,F wrote:
I would watch the carb end while working the throttle pedal. Look for sticking or slow movement when releasing the pedal.
You probably have a single, automotive type throttle cable, a spring in addition to the carb end spring, and no quadrant (arc'd channel) for the cable to ride in. Usually on bikes, there are two throttle cables that work against each other. The only spring is the one on the carb end.
The stock handle bar twist throttle has a lever arm of about 1 inch from the pivot point. Moving the cable connection on the pedal end more than 1 inch from the pivot point would make the pedal more sensitive than stock if the carb end is stock.
The quadrant is like a cam lobe controlling the pedal to carb arm ratio. A quadrant that stays the same distance from the pivot would have a consistent rate of cable pull from idle to full throttle. A simple lever with no quadrant has a decreasing rate of cable pull from idle to WOT.
IMHO, the preferred set up would be a quadrant that gets further from the pivot as the throttle is opened. It would be less sensitive near closed throttle (when you want to be smooth) and more rapidly apply full throttle. Also, pedal travel would be less compared to a simple lever.
Agreed 100 percent. Being from the bike world he is exactly right. On a bike the ratio of the throttle bodies opening becomes smaller as you twist the trottle in a linear speed (equal throughout).
Think of a cam lobe. When you first start twisting the throttle the radius is small. As you twist it more the radius of the lobe that the cable rides on increases in radius.