TFI Settings-Did I do it right?

[fireman68]

I know. Not another TFI setting question, but bike is running good. I just wanted to check and make sure I set it right.

Pot 1-I reved the throttle up to about 2000 RPM and put the throttle lock on. I then turned pot 1 until it started to bog down slightly and then backed it off a little. I took the lock off and let it go back to idle and then adjusted the idle (with the black idle adjustment knob). I then redid everything again until I ended up with pot 1 at 3 (my old eyes can't see any numbers, so I am guessing the numbers are the same as a clock).

Pot 2- I started with it at 3 and went for a ride. I was rolling along in 2nd gear and nailed the throttle. Did the same in 3rd gear. I adjusted pot 2 until it doesn't bog down when I first gun the throttle. I ended up with pot 2 at about 2:45-3

Pots 3 & 4- Before I started the other adjustments, I set pot 3 at 1 and pot 4 at 9.

So I ended up with 3, 2:45, 1 & 9. Was this the right way to set it up? These settings seem different than others I have seen on here, but I also know that no 2 bikes or atmospheres are the same.

[BudMan]

You went about it the right way.
If your bike is stock then pot 2 may be about right.
If you have opened up the intake, and have aftermarket exhaust
then I think pot 2 is low.
But like you said, no two bikes are the same.

[fireman68]

I guess I should have said I have a 2003 with dual bagger exhaust and a chuckster single-plate intake. If I increased pot 2 more, it wanted to bog down some at first when I really got on the throttle.

[BudMan]

Were you at a low rpm when you got on it?
I have an 06' with same intake and roadhouse exhaust
Pot 2 is about 5:30

[macmac]

Those settings are very close to mine. I run in economy mode with out full power, and so pot 3 is off locked back on it's stop. The bike cackels on down shifting for it. I can hold a little rpm to calm it. You may have drowned out cackel but most guys would.

My pot 4 is as low as i can turn it down leaving the pot 1 green flickering. My riding syle is rural laid back moose hunting.

I am curious what base idle rpm was just before you turned the black knob down?

And one little caution. If you down shift as normal and the bike still seems to want to go instead of slow that black knob will want more turning down.

That happened to me with in reason idle rpm the first time I set it up on the 01 1500.

IMO there isn't much of a power difference between the 15's and the 16's. I owned the 15 360 days roughly before it was stolen, riding the USA on it both ways and t hen some. After the theft i was out of a ride a while, maybe 4 weeks (grrrrrrrr) So when I got the 16 It wasn't one day to the next, but i swear i felt no more power in the 16 modded as the 15 was.

And yeah you did it about the way i might. BD does his that way. The difference for me is i don't hold that 2,000 rpm, but i could. The 914 Porche does it that way.

[fireman68]

Budman-When adjusting pot 2, I was cruising at about 20mph in 2nd when I slammed the throttle wide open. I also tried it going just a little faster starting in 3rd gear. Both times I was at pretty low rpms. If I set it much above 3, it wants to bog down for a second or 2 before it would really take off. Seamed like throttle response was best at about 3.
I don't hot rod it a lot. I lean more toward casual cruising so I would like to have it set a little more towards fuel economy (before readjusting the TFI I only got about 30 mpg on the last tank), but i also don't want it too lean to cause damage to the motor. (a little power every now and then for kicks ain't bad either)


Mac-I didn't have to adjust the idle knob down much after adjusting pot 1. About 100-150 rpm. I had also already set the TFI once before, but it was when I had the vacuum hose that had came off.
Do you adjust pot 1 with the bike just at idle instead of the 2000 rpm?


On another note. I understand what pots 1 & 2 do, but I'm not quite sure about 3 & 4. Is pot 4 top end fuel? what about pot 3?

[blowndodge]

Fireman, as mac pointed out I did my TFI the way you did. Actually I locked the throttle at 2500rpm instead of 2000.

I have tinkered with my TFI almost non-stop for almost 3 years now trying to find the "right" perfect setting. When setting the first pot at 2:45-3:00 and the second at 5:30 I could get 42 mpgs on the highway if it was most flat 70mph cruising.

Unfortunately around town in the city on a hot day it would still ping a little on premium and my milege would drop to no better than 35mpg's.

Trying to figure out why the carbed version 1500's got better mileage and could run regular baffled me as that makes no sense. Then I got an idea.

I used to just turn the idle up a little to about 1500rpms or so and tuned it that way and when I did the first pot at 3:00 seemed to give the hightest reading. Thinking about it I realized highway rpms are usually 2500 to 2750. So when I locked the throttle at 2500 and played with the first pot my highest rpms were at 4:00 to 4:30. RPM's went to almost 2800 at these numbers. Taking it up to 5:00 the rpms started to drop. Since there was no difference between 4 and 4:30 i settled at 4:00. Much higher than most run with their TFI

Rationalizing that my motor should be running much cooler I could turn the 2nd pot down substantially and it shouldn't ping so easily. Instead of 5-6:00 and turned it down to 3.

I have taken my TFI out of the side cover where it's mounted and stuck it on my tank without the rubber plug to see how much the second pot lights up. when I had it adjusted the "old way" the yellow light was on all the time allowing the accelerator pump to add addtional fuel.

No matter how gentle I was with the throttle hand that yellow light flickered all the time. Hence that's why the lower "in town" mpgs. Set the new way 4:00 3:00 1:00 9:00 the second yellow light never flickered at all unless I deliberately rolled on the throttle then it would light.

My idea was to keep the motor running way cooler at 60-70 mph rpm range that I didn't need a big shot of fuel with the second pot. So far it's worked better than I thought. My fan hasn't come on all summer, then bike never pings and I've ran a mixture of 87-89 octane in it. On my trip to the Redwoods I'm going to try straight regular.

So far my highway mileage has decreased about 1-2mpgs. My in town mileage is almost exactly the same as my highway mileage (second pot is not coming on so easily and early).

My plugs look no different. In other words they still look new at this richer cruise setting. A side benefit is that at very slow speeds in 1st gear my Nomad idles around at parking lot speeds like a swiss watch without that "lurch" when you first crack the throttle to pick up a little speed.

I'm pleased for now..

[macmac]

Fireman, Both methods are valid. My way set idle and low rpm mix just happens. The BD way is setting low end cross over mix first and getting idle mix at the same time.

So far twice i have done this my way on my own bikes and had no choice but to drop the black knob to finish setting up pot 1, and then still had to drop rpm via the black knob or suffer runaway braking, where the bike didn't want to slow down on downshifting.

My TFI is the older solder on unit, and it may be slightly different from the plug n play units. It has a 12 vot + wire i don't think the plug n play's have.

Pot 3 is high rpm mix, and the stock ecu does that well alone. What pot 3 can be used on a Nomad for is to enrichen mix for drowning out deceleration cackel. I would turn it off, and see if your bike does.

Pot 4 is a RMP counter, and tells the TFI when and how much fuel should be delivered according to the settings of pots, 1,2 and 3. It only tells the unit what to do, and adds no fuel itself.

The TFI fools the ecu into thinking conditions exist that don't.

Before this we could fool the ecu with a variety of resistors and or changing the throttle plate sencer ( varriable reostat)

The ecu see's the position of the throttle plate, which is measured by the position of the butterfly shaft, and the few other sencors, ambient air temp, water temp, barometric pressure, and engine vacuum.

The system includes no adjustment screws, as did the original Bosche D Jetronic system in 1968. The system IMO is set too lean, and so if the only mod anyone ever did to a Nomad it would need to be a primitve fuel modual, which the TFI is.

This system runs on milivolts signals from a variety of sources to include ignition pulse. All these combine to time the injectors and base line fuel pressue, with dwell (time) do the rest.

The reason the these bikes are lean is EPA regs. I consider that BS. making a engine run on less mix that it should, just makes more wasted exhaust gasses, add to the heat, wear and tear, and in the long run creates more waste of all parts, materials and adds more toxins to the air.

Then you add in worthless ethenol, which takes water from thin air, robs MPG's, and you have the very mess the Govt wants to get cleaned up in the first place.

We travel less distance making more waste.

PING is a little work crew of engine gremlins with big nasty hammers and sharp cold chisels, chopping at random all combustion chamber surfacesm and the sharper the surface the worse it is. (valve edges, and piston top to side wall surfaces are the key) But holes can be burned right dead center in a piston top too sometimes.

There is damage before PING is audible. Many vehicals have knock sencors, which force the engine to skip either fuel injected, or cut spark. Nomads don't have that feature.

Nomads don't have O2 senders either, and so IMO devices like the PC III are wasted, since the is no loop to feed back to the ecu.

This is a 1968 Bosche system the old D Jet, once revamped for Nomad anyway..... The system came to the world market first on Volvo in 1970.

Of course the parts won't interchange, so don't run out and buy a 1970 Volvo 140 series car for any parts

[fireman68]

Thanks for all the imput. It sounds like I need to quit worrying about what my settings are compared to others and just set it for what my bike tells me. Like I said, if I turn pot 2 up past 3 I don't get the throttle response I think it should have (bogging down at first). I'll check my plugs after several miles and see if I'm good on my settings.
I am still running premium gas, so I may try to set it to run regular.

[macmac]

Yup, been sayin that for years. No 2 Nomads are the same, no 2 TFI's are the same. Close but not the same, nothing is, and nothing is perfect.

No 2 pistons are the same any where on Earth. After you machine one, there is cutter wear, and so the very next one is going to different. It won't be much different, but it won't be the same.

[dmac]

I just installed Cobra true duals with Chuckster's dual plate kit and Dalbeck fuel processor. So far my numbers are with the suggested numbers on the fuel processor which are: 3, 3, 1, 9. I have an 08 1600 Nomad. I'm still trying to dial it in with the help of everyone on the forum.

[blowndodge]

Since you now have a workable setting dmac, I'd try my setting just for the heck of it. Riding double last weekend and averaging 65-75 actual MPH I averaged 40mpg's. I got stuck in stop and go traffic in Lake Elsinor with the weather in the upper 90's and the fan never came on. Climbing up Ortega highway over the mountains on regular gas the bike didn't ping at all. If my settings don't work, put it back to your settings. This is what I like about the TFI is that you can "experiment" like I did and I only took 3 years to really figure out what my Nomad likes!

[dmac]

Thanks bd for your reply. Since my last post I readjusted my pot 2 to 4 and left pot 1 at 3. Pot 3 at 1 and pot 4 at 9. That improved my initial settings. I will give yours a try and let you know my results. Thanks again, dmac

[blowndodge]

Good deal dmac!..