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Questions on TFI

Dollar for dollar and end results, it's hard to beat a properly set up TFI on a street ridden bike.
 
I have been reading all the posts on the TFI and from that information, that is what I got. I bought my bike used ( 1831 mi ) 08 Heritage Softail w/ V&H Big Shot Staggered, SE Stage 1 Air filter and the bike has a Harley Stage 1 download to the ECM. The pipes and air filter were installed by the previous owner. I installed my TFI, except O2 bypass, since pipes did not have sensors I assumed that someone had already put bypass plugs on it, and it was so rich it would chugg a lot of black smoke right off idle. Looked at my TFI install again, including O2 bypass and found the O2 connectors did not have any form of bypass on them. They are just sitting there open ended. I checked my wiring diagrams to make sure I was looking at the right connector, and they do not have a bypass plugged in. I have not been throwing any check engine lights so this seems eally strange to me. Was wondering if anyone had ever run across this??? Can the Dealer place the O2 sensors in cloed loop at the ECM as part of the stage1 download?
 
glider said:
Dollar for dollar and end results, it's hard to beat a properly set up TFI on a street ridden bike.
Click to expand...

"Properly set up" means putting it on a dyno...period. All this talk about guessing, tuning by ear, seat of the pants...I ain't buying it. The primary concern should be knowing what the AFR values are and at what RPM's they fall into. Each bike is different, and so are riding styles.

The product may be great and do exactly what it claims, not debating that. But the guesswork is exactly that...guesswork.

But, you keyed on the proper verbiage which is "properly tuned". What I haven't read yet has been how "properly tuned" is measured, other than by guesswork, feel, and listening to RPM's.

Perhaps you can elaborate on what a rider should do after the guesswork to "properly" ensure his or her ride is running at the level it should be.
 
have you ever adjusted the carb on a small engine? like your lawn mower? well its just like that, adjust the screw untill the engine runs smooth. who cares what the AFR is? it's running good. you don't need a piece of paper with all the numbers on it to tell ya that your machine is running right. all your doing is spending big bucks to have it. remember the stock fuel map is still there and the TFI is adding fuel to it.
 
Too much emphasis being put on a dyno. The dyno is only as good as the operator is and in many cases, that's not very good. How many times have we seen someone post a dyno sheet after a pull and the numbers are far from impressive.
These bikes really don't need a dyno in the stock or stage 1 configuration and at close to $1000 for a tuner and dyno work, it's difficult to justify the results of about 10-12 HP and additional TQ when you can get the same with the TFI without all the hoopla.
 
My bike was pulling much better since going through Stage 1 last week with SEII pipes and million mile AC and TFi. I found, however, that the settings shown for aftermarket components added left the bike smelling strongly of petrol at idle and getting through the juice at quite a rate.
So yesterday I set pot 4 to 7 O'Clock which is in the final paragraph on tuning and the text goes: "in some cases modified engines can produce a richer than normal idle mixtuer" the info says this overrides the other settings.

I wasn't sure if this is the right thing to do for my engine and I certainly hope I am not doing it any harm, but the effects on riding seem nothing but positive. Any comments or observations as always are welcome.

I took her out for a 75 mile ride today doing around 60-70 miles per hour and kept all the performance improvement as I'd hope; the idle is a little calmer and smells less of gasoline. As for consumption - I got 73 miles for 7.44 litres or 36.34 US gallons (that's 43.5 mpg in real UK Gallons :D:s). Which is pretty respectable I think.

Once the engine has a few hundred more miles on the clock, I'll try fine-tuning the TFi and see what happens. I must say, it seems to be a brilliant unit for simplifying customizing the fuel injection system - even for a newbie to working like this with a bike :D:D.
 
after reading the posts about the correct wiring of the TFI i went out and looked at mine but found the TFI is wired with red to both injectors. one has a set of one green and one red the other is one white and two red. is there a right or wrong way with these. i have the stock injectors wired into the proper cylinder. it is running good this way. any input?
 
Following your recommendations for TFi settings Steve, I set the posts as follows:

Pot 1 1 o'clock
Pot 2 2.30 o'clock
Pot 3 3 o'clock
Pot 4 4 o'clock

The performance from the Stage 1 upgrade is evident with this but the gas consumption is way better: I got 92.4 miles on 8.2 litres - that's about 43 mpg (US gallons) or 51 mpg (English). I'm pretty pleased with that :D.

Thanks for the advice.
 
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