Power / Performance decrease with different slip-ons.

[DeneFLHR]

Hey Steve.
Last spring, I took my bike to a very good tuner up here on Vancouver Island. The basically stock 103 with 204 cams made 103tq and 84 hp with 4" Jackpots and Rush true duals. Perfect power combo with fantastic streetability. I found it tinny and loud ater the dyno so opted to put on a set of SE Fatshotz and immediately noticed the bike was now a turd to say the least. After many calls to Bruce Schultz at Supertrapp, I arrived at the best seat of the pants feeling by installing 15 discs, open end cap. Took it back to the same dyno and it showed a net loss of 10 tq and 5 hp, (and this was the best feel I got by playing with the baffles). The once flat AFR table was all over the map now. The original tuner suggested another tune at $450 which I can't afford. (Sold the Jackpots a while ago so can't revert). He checked it over and O2 sensors seemed to function right he said. What gives Steve, any ideas on how to adjust the TTS myself in layman's terms. I have no idea what I'm doing with it but can load maps as I've successfully tried in the past. Thanks very much, Dene

[mayor]

The once flat AFR table was all over the map now. The original tuner suggested another tune at $450 which I can't afford. (Sold the Jackpots a while ago so can't revert). He checked it over and O2 sensors seemed to function right he said. What gives Steve, any ideas on how to adjust the TTS myself in layman's terms.

after reading your comments, I'm somewhat curious on what your expectations were.  If you believed that the closed loop system would readjust itself right, well that's not how the HD Delphi system works.  This just isn't an auto-tune system, even with a tuning interface like TTS.  The HD closed loop system is only a partial closed loop system.  The O2/lambda sensors will only bring the closed loop sections back in line to the predetermined afr setting as determined by the afr table in the closed loop selected areas, but this does not include wide open throttle.  How closely the sampled wide open afr matches the set afr in the afr table is controlled by how closely the VE tables match the specific engine airflow.  Once you changed the mufflers you changed the airflow which means that these open loop VE cells are no longer correct, which is why your wide open afr was no longer flat like it was when you had your dyno tune.  This isn't a problem with TTS or the HD system, both systems are still doing what they were designed to do. 


As far as adjusting the system in layman's terms, there are plenty of threads in the tuning section that discusses street vtuning.  I will say as someone with a little experience at this, this isn't for everyone, and in the end you still won't have the flat afr wide open that you had previously with your professional tune. This isn't to say that you can't get satisfactory results from doing some tuning yourself.  You just have to make sure your expectations are in line with the capabilities of the system. 

here's a good thread that discusses tuning of a lambda based system (which is what your 2011 is):
Step by step insructions in laymen terms for TTS please?

[DeneFLHR]

Thanks Mayor, appreciate the input. I'll check out your provided link even though I doubt I will get much out of it as what you said in your reply was totally over my head......but I'll try.

[Steve Cole]

Open the "MT Tuning Guide" that came with the product. Get yourself to section 4 and start reading. Once you get through section 4 and you are lost we can answer questions to get it so that you understand it. It's not all that hard but it is going to take some time and effort on your part. So are you wiling to step up and learn to do it yourself becomes the question. We are here to help you and support you if you choose to want tot learn how to do it.

[DeneFLHR]

Open the "MT Tuning Guide" that came with the product. Get yourself to section 4 and start reading. Once you get through section 4 and you are lost we can answer questions to get it so that you understand it. It's not all that hard but it is going to take some time and effort on your part. So are you wiling to step up and learn to do it yourself becomes the question. We are here to help you and support you if you choose to want tot learn how to do it.

thanks Steve