I kind figured it added fuel, I'm curious how much. What AFR value does it achieve in the cruise range? Does it change map values outside the cruise range?

 

That all depends on the bike. From all the stock bikes that I dyno'd I found that if your bike stock was running 14.1 AFR then after the stage 1 download you would be 13.8 AFR. That was just with slip-on and air cleaner. All of the downloads are up-dated to the DT2 computer at your dealer everyday if they have the DT2 hooked up to the HD network. There are different downloads listed for different year bikes as well as muti downloads for different engine configurations. Each dealer has the DT2 computer to do a download for a bike but not every dealer has a dyno to use with the SERT program. The best way to use SERT is with the dyno. DSMHAWG

 

For this discussion we are talking specifically about the "EPA compliant Stage I" download. What does that do?

 

The DT2 computer does NOT ask if you want EPA compliant. The DT2 only does EPA compliant work. For anything other than EPA compliant the dealer will use SERT or some other type of tuner. If I had a customer come in and want a stage 1 download because he had changed his pipes and air cleaner, I would use the DT2 and flash the ECM to the year of bike. A few times I had a customer ask for a dyno run for the before and after numbers. Most bikes gained some AFR but not alot after the download. Like I said if you were 14.1 before and I installed the parts (pipe&a/c) after you would be 13.8AFR when all was said and done. The download only adds enough AFR to compensate for the extra air in and air out. These downloads are set up by HD and are updated from time to time. If you have a download from the DT2 computer it will pass all 50 state EPA test if your state does that. The bike will be slightly richer but still pass EPA. Side note I have done cams, pipes, air cleaner and heads on a bike and done the stage2 download and the customer took the bike home and it ran very well and passed his states EPA test. DSMHAWG

 

You obviously have experience in this area, but you are saying a stock bike is typically running 14.1 and after the DT2 stage I down load they run 13.8. Are you talking about cruise range, because 13.8 is outside the range of the stock narrow band sensors. The last stock map I saw had a 14.6 target in the cruise range. Your info is out of alignment with pretty much everyone else that consistiently claim 14.6 AFR in the cruise range. I find it hard to imagine that 13.8 AFR in the cruise range meets EPA compliance. So is it safe to say that everyone is wrong who believes that the O2 EFI bikes are running in the 14.6 AFR cruise range.

 

You are correct. The current years are running 14.6 AFR. The last bike I dyno'd was 2009 softail. That bike had 14.1 before I had done anything to it. The only real thing I was saying was that the download does help and will work for most bikes. With that being said there are really good aftermarket options also. Ride Safe!!!!! DSMHAWG

 

This might not fit into this topic but...I bought a TTS MasterTune and finally got around to uploading the ECM calibration that is recommended by TTS for a/c and stock 2:1:2 exhaust (have oem header but Supertrapp SE slipons)


Does anyone know if this calibration is the same or close to the HD download? Or within EPA guidelines?

 

I appreciate your insight. I find your real world observations very interesting, considering it challenges popular conventional wisdom regarding actual tune condition of new stock Harleys. The goal of the O2 controlled EFI in stock form is to maintain cruise AFR at or near the 14.6 target. From your input I would say Harley is manipulating all the tolerances in the system in their favor, in order to achieve an actual 14.1 AFR out of a system designed to run 14.6. Again I find this interesting given all the assumptions based on the "lean" factory tune. I have been tuning via exhaust gas analysis for a couple years now and made some of my own assumptions based on my real world observations; one of them being that a slightly enriched tune, say 14.1 (actual), has no significant effect on heat as compared to an actual 14.6. Anyway, thanks again for sharing your first hand tuning experience.

 

from our many previous conversations my bike ran considerably better with the HD stage 1 epa download vs the canned tts canned map for my set up. Once I spent 10 hours vtuning the tts tune is incredible. the canned tts maps are set on the very safe side of things afr and timing, and that it is from the owner steve cole.

spend the time to learn to get a good/great vtune or pay someone to do it for you and you will be more then impressed.

 

Ok, sorry I missed the part about your bike running better with the HD download. Yep I do plan on getting into the vtune portion but just got it all hooked up on Friday and now away on Reserve weekend. I take it that the TTS canned map is set very close to the lean oem mapping based on what I saw on the software