Acceleration graphs

[porksword]

For the guys that arent lucky enough to have long stretches of glass water to ride on all the time or like to drag race at certain distances, holeshot and acceleration is what is most important to you. Without spending a fortune on radar equipment it can still be measured.

I used to lose a good share of ATV races because I was tuning it to give me my top speed, however riding trails, mud bogs, snow, and hills, top speed was never seen and useless. Torque and acceleration was what I needed. After a while I started graphing acceleration and quickly learned that my settings (even though faster) were much slower with acceleration in the speed range that I saw most of the time. Just from a simple timing or exhaust adjustment I could see as much as a 4 mph increase in 300'. I won alot more races after changing my tuning habits.

This can also be applied to skis. All thats required is a GPS, pen & paper, and something to mark off distance. I use the laser range finder that I use for shooting.

Mark off a set distance (or multiple distances) and a starting point. Reset your gps and WOT until you pass your mark and quickly let off the throttle. Check your max speed and it will be your speed from hitting your mark. Then move on to your next mark and do the same thing again. Pretty soon you will have an entire graph of what your doing and can measure changes through the entire range.

So lets say I made a statement like "my 800 grate has more midrange snap than my 1200". I would start behind my original starting point and bring the speed to a constant 20mph. As soon as I reached the original starting point I would nail the throttle and let off at my ending point. Compare the max speed for both grates and I would have solid evidence that what I said was correct or incorrect. It could be used on your entire setup be it grates, plates, props, nozzles, ect. Exhaust is a big one, When it sounds loud your mind is telling you its pulling harder. Is it???
Theres lots of ways to do it but it might look like this.
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