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255 S.E. cams

1. Tuners do not always agree on everything, and each bike is a little different so you don't always get the same AFR or numbers on all grafts ... ... ... Hope this hasn't been too long winded for you. Probably five other persons have answered your questions while I've one fingered my thoughts here. lol

That was a very informative reply and gave me a more insight into this area. I bought my bike used already with the SE A/C and the older SE (2007) dealer Stage1 map download and V&H pipes. It runs good but still seems to run too hot and if you roll all the way on the throttle at 60mph it doesn't seem to have normal response for a second or so. I've bought several other items and ran out of spare cash for now but plan to buy the TTS hopefully before summer. I live within 20 mins of Doc's place in Clermont so I gonna buy the TTS from him.

I looked at your profile, you've got an interesting lifetime of pictures there. You've traveled (and I surmised lived) all the way from Florida to Alaska. Really like that old chop you have. I remember seeing some of those when I got out of the Army back in 1972. Thanks for the all the information.
 
I did not say run a fixed 12:1 ratio. I said he needed to be in the 12's meaning to break that 13:1 barrier and be somewhere in the 12's. Here are two reasons why I say that.

Maybe the OP can still get pure gasoline, but my guess is he can not and is running E10.
The stoich A/F ratio (economy) for ethanol is about 9:1. Pure gasoline is 14.7 Therefore E10 shifts or pushes that ratio appox .3 of 1 ratio point to the low side. That means 14.7 which was stoich for pure gasoline now becomes about 14.4 for E10. A 13.0 to 1 ratio for pure gasoline must be set to 12.7 to 1 for an E10 equal.
This downshifting is across the board. Therefore if the A/F scaling for the OP's pull are for E10, the numbers your reading (A/F line not the Torque or H.P lines) are even lower than they appear. He could be at or near stoich for a WOT pull which is indeed way too lean by any standard. Remember when at WOT the ECM is open loop and the A/F ratio is by a look up table Only.

Another issue we must face is combined exhaust sampling. Where was the sample taken? Does anyone even ask or care to know because it makes a big difference. The rear cylinder should be setup fatter because it runs so much hotter than the front. Harley themselves do it in their front to rear VE tables. I promise you, if the OP's exhaust sample was from the rear cylinder, his front cylinder is not just lean,,, it's SCREAMING lean. So in order to cover yourself from combined sampling errors, I would notch it down a bit during WOT testing.

***As much as we all want to just ignore the fuel we are using, or ignore the use of combined sampling, we must factor those numbers (errors) in because they do add up. Lets not drift off topic. This entire topic is about A/F ratio's at Wide Open Throttle. This is not about idle or cruise ratio's. Once you let off on the throttle, the fuel map will shift back to Closed Loop and your A/F's once again be O2 sensor driven***

I am just passing information I found to be real world true, along to others.
 
I did not say run a fixed 12:1 ratio. I said he needed to be in the 12's meaning to break that 13:1 barrier and be somewhere in the 12's. ... ...

Hey Hoop, I know I learned a lot just listening to you guys. By the way I was talking with some other guys and it sounds like you probably nailed the problem on that guy's turn signal issue. The one guy had the same symtoms and said the dealer replaced the switch and it fixed it.

By the way, where did you find grade 8 SS bots at ? I have never been able to find grade 8 in SS.
 
So took the bike out for a 150 mile cruise this moring after using the button on the front of my p.c. 3 to fattin it up a tad bit and the bike is running great heads are stayin cool enough to put your fingers on for a few seconds while running and warmed with ambiant temp at around 65* or so great power no dead spots and gettin alright fuel milage for the upgrades I have made 40mpg give or take a few. The plugs got that nice brown paper bag color.
 
Another issue we must face is combined exhaust sampling. Where was the sample taken? Does anyone even ask or care to know because it makes a big difference. The rear cylinder should be setup fatter because it runs so much hotter than the front. Harley themselves do it in their front to rear VE tables. I promise you, if the OP's exhaust sample was from the rear cylinder, his front cylinder is not just lean,,, it's SCREAMING lean. So in order to cover yourself from combined sampling errors, I would notch it down a bit during WOT testing.

***As much as we all want to just ignore the fuel we are using, or ignore the use of combined sampling, we must factor those numbers (errors) in because they do add up. Lets not drift off topic. This entire topic is about A/F ratio's at Wide Open Throttle. This is not about idle or cruise ratio's. Once you let off on the throttle, the fuel map will shift back to Closed Loop and your A/F's once again be O2 sensor driven***

I am just passing information I found to be real world true, along to others.

Hoople not sure if Iam off target but on what u are saying or if the dyno chart shows it but we did a advaced map and the rear cylinderr is tunned diff then the front and my 02 sensor are not used.
 
Interesting information on fuel mixture from the SE Pro Tuner manual:

When can an engine run on a lean mixture? The engine can run on lean mixtures of say, 15 to 1, when the engine is fully warmed up and being operated under light loads, such as when holding a steady throttle, steady speed on a flat stretch of track. A hot engine though, under severe load, (such as in top gear, and accelerating for a speed record), could have a tough time running on a lean mixture, and could overheat to the point of causing itself severe damage. As a rule of thumb, for:

• Peak power a 12.5 to 1 AFR is preferred;
• Severe loads a 11.0 to 1 AFR is preferred;
• Cruising under light load a 14.0 to 1 AFR is preferred.


These AFRs are all approximate and your results may vary slightly.


The manual also states that Harley motors can run on ratios as rich as 8 to 1 under certain conditions. If you are looking for a wealth of information on Harley tuning or are simply having trouble falling asleep, I highly recommend reading the SEPT manual....:s
 
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