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Ignition timing basics
bikecarbfred - 11/11/18 at 09:28 AM

1) initial timing : this is the timing at idle with the TPS disconnected??? TPS zero?
2) total timing : this is the highest RPM timing with full mechanical advance but with the TPS disconnected. TPS ar zero????
3) maximum timing : this is the highest RPM timing with the TPS connected. TPS @ 100%???
4) idle timing : what is this? is this same as initial timing but with TPS at 100

Could someone ring where on the chart below each one is if possible please ?

I am assuming therefore on the table below.
Initial timing is 12
idle timing is 11
total timing is 36
maximum timing is at 26

correct?



[Edited on 11/11/18 by bikecarbfred]

[Edited on 11/11/18 by bikecarbfred]


chris - 11/11/18 at 10:34 AM

your tps should start at zero and your first rpm bin is starting a bit high at 1000 rpm i would set idle rpm 700 with 10 degrees of advance
depending on wot engine and fuel delivery system you are running
and any advance above idle advance at zero tps is pointless
i have mine set to 4 degrees after 1500 rpm to 7500 rpm at zero tps



[Edited on 11/11/18 by chris]


chris - 11/11/18 at 11:11 AM

if you u2u your email i will send you a map to have a look at cos as usual i cant post a picture on this forum


bikecarbfred - 11/11/18 at 12:19 PM

i dont want a map Chris but appreciate your offer and will at some time take you up.


right now i want the questions answered lol
was I right in my interpretation of each 4 points and were my figures taken from that example of an ignition map correct.

@chris. yes just noticed tps on tat example map does not tart at zero but let's assume it does.

if i can get the basic understanding then i can work forward.

[Edited on 11/11/18 by bikecarbfred]


chris - 11/11/18 at 12:41 PM

the map i offered was just an example to answer some of your questions any advance with tps off there is no ignition advance so wot is on your map is irrelevant idle advance is ten degrees any advance on your map after about 1500rpm at zero tps is pointless
maximum advance 36 depending on wot engine should be achieved at around 3/4 revs and then start tapering off
does that help


bikecarbfred - 11/11/18 at 02:08 PM

thank you . will pm you.


snapper - 12/11/18 at 05:05 PM

Most engines will have maximum total advance of 30 to 38 at 3200rpm to 3800 rpm depending on 2 or 4 valves per cylinder and chamber type
Sure there will be fine tuning above this and I know nothing about bike engines