ok, if you read the posts everyone tells you somehing different about the stage one download. I have a SPECIFIC question that I'd really like a STRAIGHT answer to and not a bunch of people telling me to forget the download and get a TTS mastertune.

everyone says that the download does not change the AFR but merely changes the timing tables and the rev limiter. they say this is for epa compliance. assuming that is true, how then does the download keep the AFR at 14.7:1 wen you add slip ons and an intake? by adding those mods it LEANS the mixture by adding more air so it would make sense that the download, although not richening the mixture to the levels that we would like to see, would still have to richen the mixture enough to compensate for the extra leanness and bring the AFR back down to 14.7:1.

this seems to make more sense to me.

I'm curious if anyone knows the ACTUAL answer to this.

 

Because the 02 sensors sense how lean it is and the ECM is still programmed to adjust the AFR back to 14.7:1

There's a lot of mythology around this, frankly. Contrary to popular opinion, if you do pipes and mufflers and AC the stock map will and can accommodate that. Your bike wont explode or burn up. The sensors will sense how lean it is and the stock map on the ECM will adjust. Granted, to the EPA mandated 14.7:1, but it won't be *worse*.

 

thanks, keith.

so it is actually making an adjustment back to propper AFR. ok. so when doing XIED's they are richening from 14.7 and not from a leaner condition with different timing. that's what I figured made sense. so many people say, including the dealer, that it doesen't "change" the afr. so a better way to say it is that it doesen't change the afr from STOCK it 'corrects' the afr back to stock levels. I can deal with that.

 

You answered your own question. The ECM compensates for the extra leaness without the Stage 1 download. The download itself affects what you said originally. It's also an extremely high profit margin for HD.

Few people can justify any benefits whatsoever.

 

I was thinking about this as well. That is what exactly does the stage 1 download do. My dealer said it does not raise the rev limiter, yet i heard it does from another dealer.

 

What levels do you want to see?


That's not correct either.

The o2 sensors simply sample the exhaust stream and reports to the ECM (assuming things are working correctly). The ECM, through various tables, decides how much fuel to add/subtract to obtain the AFR in the AFR table. The ECM then sends a signal to the injectors to apply a certain amount of fuel to hit the AFR value.

The o2 sensors sample again and the cycle is repeated.

Note: the above statement does not apply when using devices like the XIED's that take the o2 sensors out of play as they "trick" the system by adding more fuel then the ECM would have called for without them. One could use an external probe and still obtain an AFR value.

It's apparent that you have little to no understanding of the EFI system. This will allow others to take advantage of you, your bank account, and bike.

Spend some time reading and learning the system.

Good luck!

 

Well, Xieds dont take the sensors out of play, really, they take the output from the sensors and adjust the values from them that then get sent to the ECM. Basically they make the values appear to be leaner than what the sensors say so that the ECM is fooled into adding more fuel than it otherwise would - within a certain range. (cant remember if its closed loop or open loop and I always get them confused)

Thats in part why Xieds and the V&H Fuel Pak actually complement each other because they affect different ranges.

But you might have been saying the same thing.

 

the xied's do not take the o2 sensors out of play, they change the voltage range that they report to the ecm to cause the ecm to see a leaner condition and compensate by adding more fuel which in turn creates a richer overall fuel mixture in open loop. I think I understand the way it works just fine.

I was merely curious if anybody knew EXACTLY what the download does. I want to do the download as well at some point to change the timing and compliment the xied's I was just getting conflicting information on what it actually does.

question now I guess is should the xied's be disconnected when the download is done or does it matter? do they just upload a cookie cutter flash to the bike's ecm, in which case the xied's being there wouldn't matter?

 

I'm pretty sure you can leave the Xieds on when the ECM is flashed.

But here's another point to consider - by the time you buy Xieds and the download (ripoff prices), you might as well buy a Power Vision from Fuel Moto for a few more bucks and a lot more flexibility.

[edit] Sorry, just noticed you were tired of people telling you to get a TTS, well, now you can be tired of people telling you to get a Power Vision.

 

I keep hearing of the powervision, how much do they run?