The Sportster and Buell Motorcycle Forum - The XLFORUM®

The Sportster and Buell Motorcycle Forum - The XLFORUM® (
-   Sportster Motorcycle Electrical and Ignition (
-   -   Rubbermount_EVO Daytona TC88A Do your own Mapping, Tips, Questions (

xena 26th March 2012 00:06

Daytona TC88A Do your own Mapping, Tips, Questions

Ok after looking over the long and outdated TC88A thread created by Turbota several years ago I've decided to leave that mess as is and create a new thread dedicated to continue the learning experience of DIY Mapping where Ron left off. He brought a huge amount of information to the table for us by laying the foundation for custom programming the TC88A to suit our bikes, but unfortunately he disappeared from the Mapping scene and any further revelations on the hows and whys of Mapping the TC88A disappeared with him.

I know that there are many XLF members who have been dabbling behind the scenes creating their own Maps for use in their own bikes, and recently a few more have brought it to my attention that there is a need and desire to compile new info and resources here on the forum to help those interested to learn to create their own Map for their Sporty. This thread will contain questions, (and hopefully answers) and tips to help (those of us who want to learn) more about how to create a good Map for our own ride. I am what I'd consider a complete novice newbie when it comes to this stuff, but I'm a quick learner and I feel it would be a disservice to this forum for me to learn and not share what I've learned here. Especially since I've gotten so much from this forum over the years and continue to learn new things here all the time.

I'd rather not clutter this thread with a lot of the facts and questions/answers that already exist in Turbota's thread, so I'd like to suggest reading at least his intro page even if you've already read it. Here is the link to that page: TC88A Map program

For those who may want to see and experiment with the Mapping software, you can download it for free here. Download the PC Link TC88 version 7.0 It has a built in help menu and works on Windows based computers. You can actually create a Map on your computer. I suggest reading the help menu to get yourself really familiarized with the basics of how the Module and programming works.

I've gathered a little info regarding timing from various places around the web and would like to include them starting with this interesting quote. I cannot verify if this info is accurate but from what I can gather, it seems to be a good baseline in the Sportster community so I thought it would be a worth while addition to this thread:

Solving Detonation on Sportster Engines
The detonation problem with Sportster engines seems to stem from an improper advance curve. In Buzz Buzzelli's book on Sportster Performance, he describes the problem in detail. It seems that the Sportster engine runs best when full advance is reached at 3200 RPMs.
The advance curve in various HD ignition modules gives full advance around 2500 RPMs. This leaves about 700 RPMs where the engine could be over advanced, leading to mild detonation. The recommended ignition settings and advance curve for Stock, Stage I and II engines (883 and 1200) is:
Initial advance 10-12 degrees
22-25 degrees advance at 2000 RPMs
28-30 degrees (full) advance at 3200 RPM (recommend 28)
Not even the Screamin' Eagle ignition modules completely meet these requirements. The only ignitions that are able meet this criteria are some of the new programmable ignition systems like the V-Thunder. It must be noted that the programmable ignitions require a computer in order to modify the advance curve to meet Sportster requirements...
Stock timing specifications for Sportster Evo engines.
The 883 engine is set for 35 degrees of total advance. The 1200 engine is set for 28 degrees of total advance. ~ Maurice Riggins

Pic of advance curve suggested by Buzz (curve #2)

Regarding the above graph Moshe Levy writes:

"For reference, Buzz Buzzelli writes in his "Harley-Davidson Sportster Performance Handbook"
that "Extensive testing has also shown that both Stage I and Stage II motors run best if the
ignition timing at idle is set at about 10-12 degrees before TDC, is advanced to near 22-25
degrees at 2,000 rpm, and reaches full advance (my note: I believe this is ideally 28-30 degrees)
at 3,250 rpm." Back to my Dyna - Per the instructions, you start in the middle (Curve #2) and
see what works. If it pings, select a more moderate curve, and if it doesn't ping, select a more
aggressive curve. It's a trial and error job. In my application, here's what happened: Around
town (speeds generally under 50 mph, gears 1-4), no matter how much I beat on it, I could
run the bike at the most advanced curve (#1) with very minimal pinging, or at curve #2 with
no pinging. The highway was a different story. Running the bike on the highway at Curve
#1 made the engine ping like a Chinese phone book, no matter how much you babied the throttle.
Curve #2 wasn't much better. Curve #3 was tolerable, but no that great (about the same level
of pinging as an absolutely stock bike), and Curve #4 was finally acceptable. Trouble is, the bike's
acceleration, which was ferocious around town in Curve #1, was now hampered by this moderate
Curve #4. But, unless I wanted to pull over and adjust the curves based on where I was riding
that day, that's the tradeoff involved. There's really nothing I could think of to get around this
problem. So, for now, it's at Curve #4 until I find a viable alternative. One solution may be
the return of non-winterized fuel, which may relieve some of the pinging and allow a more
aggressive curve. We'll see... ". ~ Moshe Levy copied from his site here.

I recently have been doing some extensive work on my own custom Map (Xena's Black Panther)
for the TC88A, and have learned a few things about timing and my Sportster that seem to
somewhat contradict the above theory by Buzz and Maurice but more in line w Moshe Levy.

First, I've found that despite the fact that my Sporty has a 1212 conversion and aftermarket SE 497 cams, it is happiest with timing in the 30-31 degree range. In the past I've tried Map after Map and the bike either ran hot or I experienced a loss of power, or both. The thing I recently discovered through testing various Maps with all different ranges of timing was, that a severely retarded timing Map definitely without a doubt made my bike run too hot which I had read that too little timing could cause this but wasn't sure it was fact until I actually began a structured testing process. Switching to a Map that was more in the range where my Sporty felt happy immediately made it run at more normal temps and made everything more normal. Also I forgot to mention that with too little timing the spark plugs would quickly develop a black soot on the base and the porcelain went from a light tan - normal looking - to bone white. If you change to a Map that you think might have too little timing and you experience high oil bag temps (240-250 for me) and your plugs look like I described try adding a couple degrees of timing and see if things don't drastically change.

To create my Map I started with Turbota's Mod Map 1200 Version II as a baseline (Rons Mod Map 1200 V2 pictured below).

You can download any of Ron's Maps here if you'd like to use one of those as a baseline for your testing.
Note, the Map I've posted the pic of above is not included in that link so if you want that you'll have to create it by entering the values yourself.

Hopefully those of you who have created your own Maps will share your knowledge and findings about the process in general, and those who want to try and learn will participate as well. Thanks and I look forward to the learning and sharing that is imo the core of the XL Forum.

xena 26th March 2012 22:59

continuation "timing too retarded"
After I got the timing close, I could tell by not only the
way the bike ran, but also the spark plugs. With it too
retarded the plugs just looked wrong and the oil bag
temps were way higher than I'd ever seen. Here are
the pics to back up my discovery.

The only thing I changed from pic to pic was the timing.
In light of this I'm going to suggest that if your Sporty runs
hot with a Map that you think might have too little timing,
and you haven't changed any other variables, and your
plugs look close to the ones in the first picture, I'd
suggest adding a little timing if you're running a Map that
only has 28 or 29 degrees. Start with fresh plugs for your testing.
I run 10R12A and comparable heat range NGK (I forget the # for those).

Timing too retarded:

Timing closer to correct:

~Grind~ 26th March 2012 23:52

Wow! I haven't put much thought into how timing would effect engine temps. I've seen those dip stick thermometers around. I'm going to have to get one. Digital or analog? The Buell heads I purchased have a tapped hole in the rear head for a heat sensor. I wonder if I may be able to use it too?

xena 26th March 2012 23:57


Originally Posted by ~Grind~ (Post 3865820)
Wow! I haven't put much thought into how timing would effect engine temps. ...

Scott neither had I but I knew one thing. When
I began messing with timing Maps that had the
timing retarded too much, all of a sudden the
bike was running hot out of the blue when it
never did before and I could never get the
plugs to look normal. It's also worth it to note
that even upping the jets and screwing with the
mixture wouldn't change things, IF the timing
was set far back. While I am seeing my
timing needs to be a bit less than a stage 1
stock Sporty, it doesn't need to be retarded as
much as everyone would assume.
Now this is my own bike. Someone else's may
not be the same deal.

~Grind~ 27th March 2012 00:05

I hear ya, If I'm not mistaken your bike is running NHRS 1212 pistons, honed cylinders with stock 883 heads. It seems the further away from home plate you get from the original engine design parameters the more things change... One size does definately not fit all.

xena 27th March 2012 00:11

Yes, 1212 conversion w 10:1 compression pistons
and now the SE 497 Cams too.

Fwiw, Racerwill has a conversion on his Sporty
as well and he said his likes somewhere between
30-33 degrees. I think it's a gray area and what
it ultimately comes down to is that every bike is
going to be different so don't assume just because
one has all this engine work that right off the bat
it's going to require 28 degrees of timing.
I'm just glad to have made the discovery instead
of going around in circles with it. Now I can work
toward fine tuning and getting it perfect. :D

This new information might help Rico and some
of the other guys with their 1212 Conversion Maps.
Rico told me in his opinion he couldn't write a Map
for a 1212 that made it run just right. Probably
because everyone was stuck on thinking "less timing".

jayman79 27th March 2012 00:53

Subscribed, good info, thanks.

xena 27th March 2012 17:18

Thanks Jayman I sure hope all of this compiled
in one place will spark some input from
expert engine builders and also members
who want to learn how to work with this
module on their own.

Gathered more interesting information today.
Don't know what to make of it but I know
someone who has vast knowledge in the
area of timing and Sportster will weigh
in at some point. I do find it puzzling that
some of the experts who build bikes can
recommend and use the TC88A yet not
use a custom written Map.
At least one person who is imo an expert
with Sportster engines and Dyno Tuning had mentioned to
me that "honestly I tried a couple of
custom TC88A Maps but never saw any
better results than using the switches at 0,2
(or was it 2,0?)but didn't want to say anything on the
open forums because people seemed
proud of their Maps". I'm not going to
mention names because he obviously
didn't want it noted publicly
which is his prerogative so I'm going
to respect that.

Back to the meat and potatoes.
Some of the quotes I stumbled on
that I thought belong in this thread: states:
Stock timing specs for Sportster Evo engines:

The 883 engine is set for 35 degrees of total advance.
The 1200 engine is set for 28 degrees of total advance.

From the Harley Davidson XL
Sportster 2004-2006 by Clymer:

"The ignition system fires the spark plugs near
top dead center for starting, then varies the
spark advance from 0° to 58° depending on
engine speed, crankshaft position, and intake
manifold pressure".

And this quote from xlf'er FoxsterUK
claim three years ago in Turbota's thread:
"The max advance on the TC88A is 45°.
At low load & high RPM this isn't enough.
You get detonation on closing the throttle at WOT. You need 50° under these conditions".

Here are a couple of Maps from Sportster timing map tables supplied with a SERT for a '04-'06.
You'll notice the Maps are not from a TC88A .
The reason I wanted to include these is that you'll notice
50° of timing in there. Yes that's right, 50°.
This brings about questions that have never
been answered. Since the TC88A has a 45° limit
among some other limitations, we couldn't even duplicate
those numbers in our Map if we wanted to but still raises some
questions for me.

Stock 1200 Cams for the first chart and 1200 W Cams for the 2nd chart. I believe these Maps
are measuring in Kpa (0-103) where the TC88A measures by in-Hg (16-30).
A couple of members in the past have used Excel to convert that data. One that comes to mind is
Kirk the Jerk.

chrissenator 28th March 2012 12:28

Thanks for a informative thread Xena.

I struggle figuring the timing on my 2007 883 converted to a 1250 - I have the PowerVision thingy and fiddeling with that,, but I have read so much fourth and back on timing for my build that I have lost track of it!..
I can adjust and play around but wheres the limits and where to aim?

Stock cams, stock 883 heads and a NHRS 1250 kit...

xena 28th March 2012 16:20

Yw chrissenator. Only thing is, the TC88A and
your Power Vision are different animals. I know zero
about EFI Mapping but I do know that the
TC88A measures pressure using in-hg and yours measures in kPa.
You might however be able to use the two SERT charts
I posted above as a baseline reference but I gotta believe
that there is an easier way for you. Have you looked
at Sportytraces thread? Maybe it will help I don't know.

All times are GMT +1. The time now is 18:32.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.
XL Forum® - Linson Media LLC