The tables in question are under the "spark" tab. There are three tables...you will chose two of them.

From DJ..."The air cooled engines use the “spark adjust vs. head temp” table., where the liquid cooled engines (think V-rod) use the “spark adjust by engine temp” table.


So, on the PV gauges “Engine Temp” is really “Head Temp” on an air cooled engine, and “Engine Temp” is “Engine Temp” on liquid cooled engines. In either case, this channel is representing how hot the engine is."


So, on my FLHTC, I use the Adjust By Air Temp and Adjust by Head Temp.

 

Thanks... much appreciated.

 

Thanks guys! I'll start at 300.

 

I changed my rear wheel and tire combo from the stock 16" wheel with MU80B16 rear to a 150/70B18 rear. Since the new setup is a little taller I was wondering if anyone could suggest where I should start at with the Speedometer Calibration value to get it back in line. I haven't checked it with a GPS or anything, just figure with the taller tire the speedometer would be off.

 

So explain to us exactly what you have been doing. From step 1 to step X. How have you been making changes to BOTH tables? Start from the minute you fire up the bike, how you identified the knock, at exactly which temp, what change you made to table X and what change you made to table Y. Tell us what the air temp was (how did you determine this), tell us what the engine temp was (how did you determine this), tell us how you determined it was temp related and the exact change you made. How did you determine the knock was from air temp versus engine temp? Was it from both? Did you make changes to both tables? Why? Why not? One liners don't tell us much. So please, explain exactly what you have been doing...and just as important....why. You said..."So, on my FLHTC, I use the Adjust By Air Temp and Adjust by Head Temp". I, as I'm sure others as well, want to hear the entire story. You walked into this one dude....step up to plate. Tell us your secret.....no guessing either, lol.

 

Until you know how far off it is it's gonna be a guess. GPS would be your best bet, and then play with the pulse value. I have to admit I don't have a clue where to start. Would be nice to hear what you figure out for those that are in the same boat. Every little bit we can learn from each other is cool.

 

If you get jammed up come back and ask. Between all of us I'm sure, well maybe not lol, we can help you out. Just ask. Every question helps ALL of us in one way or another.

 

Wrong answer to the question for sure. Lemme look and I will give the correct answer. Here's the deal, so you know. It IS best to tune in spring and fall. Nothing wrong with Summer tuning, but this will work backwards.

In the cooler months, and engine can use more timing and one gets to enjoy a bit more pep and the engine LIKES that timing.

When the weather heats up, it becomes too much timing, the engine pings. One would THINK... go pull timing back out... THAT will screw the tune for two seasons if one does that. Instead, there is a Spark Temp Correction table somewhere. It will look like a spark table but have a bunch of zeros and a few negative numbers the closer to the bottom and right side. The upside axis will be in degrees of temp. Upper is lower outside temp, lower is high outside temp.

Most NEVER fool with this table as it usually is decent or folks shouldn't change crap they don't know about, but here's the deal.

At higher temps (lower on the chart) and more to the left (Higher MAP or AFR)... those negative numbers say to the ECM how much timing to pull out of the ambient temp is such-and-such.

Tune when it is cool. Then in summer, if it pings, go chase that ping down. Say... you find it pinging at 3500rpms and 60 MAP. See how MUCH it is pulling timing wise when you find it, too. Then, instead of going to the spark tables and start removing timing, go to spark tables and increase that negative number around your 3500/60 by like a degree of timing. Work THAT until it quits pinging and then summer AND spring/fall the timing will be in a way better spot than having quick retard or learned timing pulling a whole bunch of timing.

Besides the obvious on summer/ spring timing... the temp table works better when really hot because timing can end up being a bitch. The ECM will pull some fast retard... it doesn't go away, so then it starts keeping the timing pull in learned timing. Once the timing IS pulled, now the engine will run hotter and hotter because TOO much timing is being pulled. Fast retards job is to pull WAY more timing than needed to protect the engine, NOT to make it run correctly.

I will now go try to find that table in PV.

 

Waiting on Wurk...

 

I think you will need an external check on your bike speed, like a GPS. When you do some runs, and observe your speedometer at 60 while the GPS reads something else, then you have a starting point. If speedometer reads 60 and GPS reads 57, you have a 5.26% variance. The table value in the PV is something like 2100 (yours may be different), so take that value and change it by 5.26% or 110 and that should put you right on. I left my speedometer about 1% high (when speedometer reads 60 I am really going 58-59), but that's just my preference.