Timing curves

[rodneya]

Can somebody give me a simple explanation of the difference between curve 1 and 3 on the attached

[Striker1423]

Can somebody give me a simple explanation of the difference between curve 1 and 3 on the attached

Oh good, graph's written in morse code!

Well, based on my hairy eyeball's glance it looks like curve 1 is an aggressive advance earlier in the rev range, while 3 is a slower advance, later in the rev range? I can assume it's for building power at different ends of the spectrum? One's maybe better for the low end, and the other for the top end? But, I'll leave the actual answer for someone else who fiddles with this stuff.

[m in sc]

the one with the long flat curve is NOT for street riding per-say. you'll wind up at max advance at cruise and probably run hotter than desired.

kind of depends also on the porting & pipe characteristics. IF it were me, id probably start with curve 1 if there was any low end loss with porting and pipes.

none are that aggressive, most of the aftermarket acrd ones are like 24 max.