breaking news from my freeway test session ride:
- around the block you can test the lower left map point only; that'll be coasting in 5th doing a steady 50mph
- you can't test drive a map within city limits, you'll always read "rich" when glancing at the meter thanks to some throttle wick fuel addon mechanism
- on the freeway, especially on a substantial hill, "all sevens" is lean at WFO from 40 till 100 mph, you'll hear the pinging! (but okay I had the iginition still advanced!)
- as an immediate countermeasure I retarded ignition from my stupid +2 to late -4
no more pinging, piston saved, but no more power as well, but that was to be expected
- next thing I did was crawl to rich on all full throttle map points,
(top row, easy job: facing looong freeway hill, in top gear whack throttle WFO going 40mph and wait)
- next was checking 1/8h throttle maps points for avoidance of lean at higher rpms,
e.g. making sure even in thrid(!) gear going downhill at gazillion rpms I'd be a tad on the rich side
the resulting fuel map for the non pea shooter exhaust tip:
-5 -5 -5
-7 -7 -6
-4 -4 -3
- the -4 in the lower left still is lean when coasting at 1/8th throttle. I'll leave it there, saves fuel and keeps the exhaust clean.
- the hardest to dial in is "medium throttle", I'm not sure if these -7s really run rich
- with that map you only see "lean" at very low throttle opening and low to medium rpm, anything else reads "rich"
Considering my eariler calculations that max. power (A/F 12,5) needs 16% more fuel than an A/F of 14,7
and remembering that one step in PowerTuner fuel map is 3% acc. to YAMAHA (manual and video)
one needs to PowerTune to 5,3 (16%/3%) steps richer that perfect A/F, it apperas that
PowerTuner fuel=0 already is the max. power A/F ratio, for my bike and exhaust and ....
Good job YAMAHA
(rationale: with the -5 in the WFO row of the fuel map I didn't see "lean" anymore,
with -6 in WFO row there were lean occasions,
so these 5,3 steps richer than perfect A/F ratio lead directly to "0" as map value)
Edited by WRF-Rowdy, June 26, 2015 - 05:12 AM.