...you wouldn't really notice much difference in the beginning..say your at idle, and you "punch it"..you'll start to gain speed pretty much normally until you hit the "sweet spot" of rpm range that your cam is designed to make it's power at...at that moment you'll feel the bike really pull, a little like a turbo-charger feel, except much milder of course...then it will taper off at it goes past the range...then your buddie who you left in the dust, comes roaring by with his "high range" cam!...

 

Cams don't change RPM's, they change the power developed at any given RPM. The only way a cam change will cause changes in your low speed maneuvering is if you install a radical low-end cam. That might get you a pretty quick stop light to stop light drag bike, but wouldn't be much good on the highway. Any but the most radical cams will produce more power at all RPM's, but you can control that with the throttle. The point where the cam "comes on" is the point where it begins to produce the best response when accelerating. Again, controlled by the throttle. If you're looking at mid & top end cams you'll feel a mild improvement at parking lot speeds & putting around the neighborhood. Hitting the highway will impress you the first few times & then become "normal". At times you'll simply notice that when pulling on to an Interstate, or passing, the bike simply feels strong & whatever you're doing takes less time & effort. Put simply, if you don't get radical a cam won't hurt your low speed handling, & will make you happy at speeds you normally ride.

 

Each cam lobe only affects the moment a single valve opens and closes.
If you have a sufficient provision of air and fuel, you obtain the optimal power the cylinder can produce. Since air is compressible (elastic) sports cams try to stretch (by anticipation) the duration of the admission cycle and you have 'reflux' at low rpm that doesn't allow to fill the cylinder completely with fresh air for the coming compression cycle.
Below 2,000 rpm you may need to compensate the loss of power with the clutch. But at higher rpm sports cams 'give a better chance' to fill the cylinder.

 

It is the moment your face contorts into a smile!

 

Lets start with the easy stuff, Harley motors normally run between 1000 rpm (idle) and 6200 rpm (redline), even a top end cam for a Harley isn't really all that radical because of the rpm limits. Now, If Harley's had a redline of 11,000 rpm and you had a topend designed cam,with correct head porting, correct timing curve, matched intake and exhaust, then yes, you would feel when the bikes rpm got into its power zone, It would be a surge in power you could feel, and the engine would be not very friendly at idle as the cams valve timing would make the engine very uneven as the systems would be designed to work at a narrow band in the upper rpm range, say like 7000 - 11,000 with much less power below that range. I had a 400 Chrysler wedge engine, injected on alcohol that was built to run in a dragster, it's sweet spot was 7800 rpm, but made great power from 6500 - 8200 rpm, and that was how I ran the car, launched at 6500, shifted at 8200 and went through the traps at 7800. Car idled at 1200 rpm, but if you floored it at that rpm it would fall on its face.

 

10 y/o thread

 

Nice resurrection. I’ll add my summary.

The more extreme your cam lopes, the higher RPM the power comes on, and the more difficult it is in low speed maneuvers. Sure, you can tune some if it out, then your killing the advantages of the wild cam, and might as well get a more mild cam.