I just installed a Hardline RPM/Hour meter on my 08 KX450F. If my rpms say1680 what is the true RPM and how do I figuare it out? Im sorry if this is a stupid question but im new to these 4 strokes.
Thanks for the help.
Mike
RMP/Hour meter ?'s
Started by 04CRF450, Oct 26 2007 02:25 PM
7 replies to this topic
Posted 26 October 2007 - 02:25 PM
I just installed a Hardline RPM/Hour meter on my 08 KX450F. If my rpms say1680 what is the true RPM and how do I figuare it out? Im sorry if this is a stupid question but im new to these 4 strokes.
Thanks for the help.
Mike
Posted 26 October 2007 - 02:47 PM
Most Hour meters with a tach read induction pulses from your spark plug wire. So each time you spark plug fires your tach reads a pulse. How many times your spark plugs fires per minute equals RPMS. 1680 RPMs sound like just above idle on most modern thumpers.
Posted 26 October 2007 - 03:55 PM
So would I devide what I see on the screen by 2 to get the true RPMS?
Posted 27 October 2007 - 05:40 AM
No, all bikes even 4 strokes spark every revolution. It just has gas and compression every other stroke. The crank sends a firing signal every time it passes the pickup coil. The crank turns twice for every time the cam turns once, so it sparks on the exhaust stroke also.
Posted 27 October 2007 - 06:39 AM
You would not have to double or divide, it should be correct if your hour meter/tach is working properly.
Posted 28 October 2007 - 10:39 AM
04CRF450 said:
It is working properly im just trying to figuar out how to read the RPMS. If the manual says the RPMs should be between 1 750 ~ 1 850 r/min and my meter says 1680 do I need to bump my idle up a little?
You can if you'd like. I run my idle higher than 1850....
