rev limiter/ignition cut off on a carbureted bike

[koalaKid]

How does it work? I assume there are a few different designs.

Can anyone shed some light on this? I'm curious.

 

[TwistedKestrel]

The vast majority of carb'ed bikes out there have an electronic ignition. Some of them are fancier than others but on any bike that has one, the rev limiter is implemented there. Since they're not that complicated, anyone looking to raise the rev limit on the bike will probably replace the unit with an aftermarket one (e.g. Dyna ignition).

 

[koalaKid]

do you know how it senses engine rpm and feeds that back to the ignition system? Does it cut spark generally, or does it change the timing?

 

[TwistedKestrel]

do you know how it senses engine rpm and feeds that back to the ignition system? Does it cut spark generally, or does it change the timing?

Crank trigger - most carb'ed bikes will have an accessible ignition rotor on the left hand side, underneath a cover. The ignition module uses this information to control ignition timing relative to load and RPM, and also uses it to trigger the rev limiter. It will cut spark.