Crank vs. Cam sensor

[HDLARRY]

I've read a few posts suggesting doing away with the crank sensor and installing a cam sensor. This was in regard to installing an after market ignition system. This has puzzled me so maybe I can learn something here.

My understanding has been that a crank sensor is a much more accurate way of running your ignition timing. This is because the crank is directly connected to the piston position through the connecting rods.

When using the cam sensor there are gears connecting the crank to the cam. This introduces a potential timing error due to slop in the gears.

So if a person has a choice, wouldn't you want to use a crank sensor for the ignition system?

 

[dogvet]

In my opinion, the crank sensor by itself isn't as accurate as the cam sensor. the cam rotates at 1/2 the crank speed (better resolution). There is the potential for error in the cam sensor due to gear backlash, but as long at the timing is set with a timing light and not static timed, the backlash doesn't present a problem.

With a crank sensor, the crankshaft has to make a couple of revolutions in order for the ignition module to determine which stroke it is on (not a problem with a dual fire (waisted spark) ignition system.

That's just my opinion.

 

[Gas Man]

For me its a simple matter of... I don't want more eletronics on my bike... the cam cup is better for me. A bit more old school.