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no tuner needed?

update on performance with stage 1 and no tuner..the bike runs well. right now it is only 50 degrees here, perty cold. i was able to get some riding in today. lots of power, every now and then the idle air controll will search a bit. not all the time, just once in awhile. no popping on decel, what i have noticed is on some occasions about 2500rpm, at a steady cruising there is faint , very light surging, once in awhile a small backfire or two.. my final opinion is, it runs fine without the tuner, but to have it running proper all the time, a tuner would not be a waste of money at all..more performance numbers to come...stay tuned.:57:

went to century harley today for the dyno shoot out. now today the bike on the shop dyno made 74 hp, with the d and pipe, heavy breather..previously with the stock exhaust and heavy breather the bike made 79.5 hp, i wonder if the portable dyno at the bike rally was a set bit high. anyhow they gave out 20% off cards today so i purchased the sest pro and left my bike to be tuned. i will post results when done. like i said before it ran fine with no tuner, low rpm slight surge, not bad. what i have found is the o2 sensors adjust only in low rpm range, at high rpm it goes open loop to the 13.8 afr factory mapping, also the factory map doesnt give you full throttle in low rpm, it actually regulates it.. more learning needed, let you know the results when done:newsmile082:
 
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The AFR line in those images is rather inconclusive to me. I cannot see the scale which is evidently on the right margin. The red dashed line is arbitrarily placed where? 13.2? What was this, a 4th or 5th gear full-throttle run? If so, remember that the actual throttle opening on the DBWs doesn't always exactly follow the twistgrip. It's proportioned at the lower rev ranges to not open too much too soon.

The AFR reading also wouldn't represent much closed-loop operation, and would include "power enrichment" fueling, too.

The new O2 sensors are most likely heated versions of what we had before. This gets them hotter quicker and "consistentlier," prolonging their life and accuracy. This also enables their placement further down the pipe where the environment is less harsh. They are not placed after the cat as this would be completely impertinent for the way they're used.

Their altered distance from the heads certainly necessitates a different sample timing, but this is a simple feat. Cars have been using for some time just one sensor in a manifold, with timing from the combustion events being used to determine which cylinder's exhaust is currently being measured.

Probably the main difference with the newer EFI parts/programming is that the closed-loop bias tables have been eliminated. The "AFR" table now uses discreet (more meaningful) "lambda" values; with a range of values corresponding to "closed loop" mode. The end result is largely the same as the old "14.6 + CLB" but is much finer-grained. One other thing is that the VE tables are now also "load-based" (RPM v. MAP instead of RPM v. TPS).

There might be a more elaborate "adaptive fueling" mechanism now too; I'm not privy to that information. Either way, I'd much prefer to alter the native tables as necessary for breathing parts and allow the adaptive fueling to operate in the center of its range instead of relying on it accommodate owner-induced tuning changes. Such accommodation may be pretty good, but it won't ever be perfect, and it'll fer sure use up valuable system headroom.
 
here is the dyno sheet with sest, d and 2into1, heavy breather,
jjdh-albums-exhaust+install-picture2702-stage_one_sest_d_and_2_into_1_heavy_breather.jpg

here is the portable dyno sheet, stock exhaust, heavy breather
jjdh-albums-exhaust+install-picture2701-portable_dyno_stock_exhaust.jpg
 
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