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Stock settings for a TFI

The throttle is only giving "values" to the control module and the module takes it from there so you probably are pretty close in what you say.
 
I honestly feel that the throttle responds differently every time I start the bike. Sometimes snappy, sometimes sluggish. I have yet to do any kind of download or remapping, hopefully it'll help.

If you havent had the throttle download to fix the high idle yet get it .. let me tell ya it makes getting a correcting with tfi very hard if they havent resynced the throttle to the servo as the download does
 
The throttle is only giving "values" to the control module and the module takes it from there so you probably are pretty close in what you say.
I can't say what's going on in the stock programming, but here's a screenshot of the "throttle blade control" table in the TTS stuff. I'd assume that after 2500 everything's 1:1 but the bottom row may continue for any higher speed.
 

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... too late to edit previous post.

I wonder. Does the TFI key on the twist-grip sensor or the throttle-blade position for its calculations? If the latter, it shouldn't matter.
 
Neither, it modifies the signal for the injector pulse width sent out by the ECM downstream from the ECM depending on the settings used on the TFI.
 
Well, I fetched the manual for a TFI. If I'm reading it correctly, the only connections are made at the injectors and a ground wire.

Engine RPM and the rate of RPM change would be easy-enough to derive. I suppose the engine load could be fairly-well determined in the presence of a fair amount of pre-loaded data, but in this case it would have to be pretty generalized. Oh, well. I guess I'm wondering how they're basing their claim these things are "load-based".

My real question is "Why?" but I don't want to get into that so much here. I accept y'all are happy with it.
 
I would say the "load based" comes in from the use of the sensors on the throttle body. The TFI is a simple unit that most anyone is capable of installing and setting up without the knowledge required with the more complex units with mapping. Also the possibility of damage to the engine from modifications to Ignition are not there with the TFI.
While it's true that other units offer more adjustment in more areas than the TFI, I feel for a street ridden Harley, it's excessive and there are many that run the bike with the stock map from the factory and are happy with the way it runs.

The TFI gives the advantage of eliminating the lean factory conditions without getting in over the heads of the non mechanically inclined. I think it fills an area that most riders fall into that don't have the ability to data log or make the adjustments to maps and allows a bit more fuel to be added without the headaches and time required that the more complex tuners require. For the less mechanically inclined, changing maps and setting VE and the other settings is a very comprehensive task and computer skills come into play with the more complex units that would open up the door to problems if the person wasn't sure of what they were doing.

If a person has deep pockets and wishes to get into the more expensive tuners at about three times the price of the TFI which would include a dyno tune and custom map , there are the option of the dealers and the dynos which is an area that I will not even breach here as far as good tuners. We are at their mercy as to who knows what they are doing and gives you a good job. I've seen plenty of "tuners" that I wouldn't let near my bike.
If you happen to have a good tuner and they are affordable, the options are there for a decent tune if you wish to spend the money for roughly the same gains in power with the high priced tuners as you get with a TFI. If we see 10-12 HP gains and additional TQ with a TFI, stage 1 and slipons, I find it difficult to justify $800-$1200 for the high priced tuners and dyno time with little more in return.

JMHO.
 
closed loop for the later bikes i see what your saying but for a bike with the narrow band sensors that wont change the fuel or change it slightly pretty much all 08 and earlier doesnt much matter

Everyone has there fav tuners not saying a tfi is perfect but neither is pc III .. and neither is harleys early Closed loop
 
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