I was just perusing some logs and noticed that IAC follows TPS (and INJ PW) quite closely. The shape of the log graph is nearly identical. That seemed a little counterintuitive to me, I would've thought that with TPS opening more that IAC wouldn't have as much of an effect and need to open too..... Is this done in order to somehow smooth out rapid changes in TPS (along with the enrich/enlean)? I seem to get some pretty lean spikes when that happens. maybe just need some more tuning in those areas, but just wanted to ask the question about the IAC operation.
Quote from: jjdalynh on October 05, 2018, 08:19:37 AM
I was just perusing some logs and noticed that IAC follows TPS (and INJ PW) quite closely. The shape of the log graph is nearly identical. That seemed a little counterintuitive to me, I would've thought that with TPS opening more that IAC wouldn't have as much of an effect and need to open too..... Is this done in order to somehow smooth out rapid changes in TPS (along with the enrich/enlean)? I seem to get some pretty lean spikes when that happens. maybe just need some more tuning in those areas, but just wanted to ask the question about the IAC operation.
Yes it follows to a certain limit. It prevents a sudden slam shut of the throttle blade going back to 0% tps.
Ron
What should IAC be at idle at say 200deg F?
Don't know what it should be, but I looked at a few logs from different bikes and they were both about 46 at 200F and steady cruise. Both were wet heads. Looked at a 11 model touring and it was 46 also.
Quote from: KE5RBD on December 19, 2018, 03:53:53 PM
Don't know what it should be, but I looked at a few logs from different bikes and they were both about 46 at 200F and steady cruise. Both were wet heads. Looked at a 11 model touring and it was 46 also.
I found a direct relationship to how much the blade is set open in regards to setting the tps volts on the idle stop. If the blade is more open, the IAC steps will be slightly lower and visa versa. Not that it matters, I think I remember my 120 being in the 28 step range around 200*. Still had range to work.
Ron
Quote from: KE5RBD on December 19, 2018, 03:53:53 PM
Don't know what it should be, but I looked at a few logs from different bikes and they were both about 46 at 200F and steady cruise. Both were wet heads. Looked at a 11 model touring and it was 46 also.
Cool, that's where mine are with the new cam around 44-45. Throttle at 5% blade5%