BT ECM on a Sporty

[Screw Loose Dan]

Hey guys, I've been a lurker in the past but now I'm onto a project I could use a hand and advice with.

I am trying to get a BT ECM to work on my 2007 Sportster.  The reason for wanting to do this is to gain the ion knock detection that the BT's have.  I think this would be a really useful tuning tool as well as providing a margin of safety.

I have a BT ECM off a touring bike setup with a SERT.  Most of the wiring is identical as far as the ECM goes and I have all of that sorted out (the system relay pin changes and there needs to be an extra wire for the ion sensing run to the coil).  The bike runs and fires fine.  And I was even able to see knock detection working.  I am using a heavily modified 176PZ005 map file.

The issue I am encountering is that the ECM reports incorrect MAP, ET, and possibly IAT temps.  I am sure I could retrofit the sensors from a BT over to the Sportster (and may ultimately try that).  But, I am guessing that the calculations for the sensors resistance/voltage is all handled by the map files.  I would prefer a software solution (as opposed to swapping the sensors) because during my testing I like to be  able to switch back to the Sporty ECM rather quickly and it keeps the cost down if others want to do the same in the future.

As an example of what I am seeing, I just did some real quick tests without running the bike (and it completely cold):

Ambient temp: ~ 5° C

Sportster ECM

• IAT: 10° C
• ET: 7° C
• MAP: 100.0 kPa

BT ECM

• IAT: 19° C
• ET: -16° C
• MAP: 86.7 kPa

A few real quick tests but not back to back with the bike warmed up show similar results:

Sportster ECM

• IAT: 45° C
• ET: 166° C
• Idle Load MAP: ~ 52 - 55 kPa

BT ECM

• IAT: 50° C
• ET: 87° C
• Idle Load MAP: ~ 48 - 51 kPa

So, I suspect the IAT might be off slightly but clearly the MAP and ET's are way off.  Shifting my maps might be another solution (although much less elegant), I'm not sure how this will mess with warm-up routines and heat managment cycles.

So, I'd like a map with the ion knock detection, O2 sensors, and Sportster sensors.  I don't even know if that's at all possible.  I'm hoping someone might have some answers or be able to offer some guidance.  I'm currently using a SERT, but actually would like to switch to a TTS.  I have the TTS sitting here waiting to be married up the BT ECM.

[FLTRI]

Your best bet is to contact TTS (Mastertune.net) and ask Steve, who did the SERT for the MOCO. He will probably be the best bet for answers to your questions.
HTH,
Bob

[Screw Loose Dan]

Your best bet is to contact TTS (Mastertune.net) and ask Steve, who did the SERT for the MOCO.

I absolutely  agree with you and I actually did start there.  I have exchanged a couple messages with Steve, but I didn't get the feeling from his initial response that he was eager to assist with my pet project and I'm impatient waiting to hear back from him again.  I can't really blame Steve as I understand he has been quite  busy and what I'm trying to do is quite outside the norm.

Steve seemed to indicate (if I got it right), that he was unsure that the ion sensing would work properly or at all on the Sporty.  He also stated that the sensors were not the only problem I would have.

So, I was hoping someone else might have some insight in how all this works.  I did get excited when I saw that the knock detection appeared to work in my initial testing, so I'm holding out hope.

[Hogflash]

One thing to note is that the Sportster uses a different engine temp sensor (its calibration is different) from the BT, as it is located in a hotter location.  You will need to use the BT sensor to work with a standard BT cal - and, it will need to be relocated such that it mimics the BT temperature readings as the engine warms up.  I think the MAP and intake temp sensors are the same, but the ECM may read the MAP a bit differently due to the timing of the MAP reads by the ECM.

Steve could probably build a BT cal that uses the Sportster temperature sensors and map read, but he would need to be convinced there is enough market to warrant the time spent doing this!  --and, this may be the easy part as the ion sense system may need to be recalibrated to work correctly with this engine.  No guarantees!

[FLTRI]

Rufus has some very valid points. Mess with it long enough you may be able to get the bike to run as good as a properly tuned Sportster system.
Good Luck, and keep us informed as to your findings,
Bob

[sportytrace]

I think the MAP and intake temp sensors are the same, but the ECM may read the MAP a bit differently due to the timing of the MAP reads by the ECM.

Hi guys,
Please bear with me, I'm just learning all this.... but I thought the MAP sensor reports 100 back to the ECU when the motor is dead and the pressure in the intake is the same as the ambient air pressure. So in this instance if the sensors were the same between the sportster and the BT wouldn't they both be reading 100?? It would appear from the initial post that is not the case (Sportster = 100 at rest; BT=86.7). I'm not sure how the timing of the MAP reads by the ECM would affect this at-rest reading?

Steve could probably build a BT cal that uses the Sportster temperature sensors and map read, but he would need to be convinced there is enough market to warrant the time spent doing this!  --and, this may be the easy part as the ion sense system may need to be recalibrated to work correctly with this engine.  No guarantees!

It sure would be nice to feel like we had the "security" that the Knock sensing gives- especially given how hot these bikes get down here in summer.

[Scotty]

You would need to check part numbers but the Sportster throttle body, injectors, ETS and a few other bits are different.
I think unless you have access to the program to make the map that it will take a lot of ingenuity to make it work.
I know Steve Cole could make a map as he has access to the templates and could adjust but maybe he doesn't have time or is not interested.

[Screw Loose Dan]

You would need to check part numbers but the Sportster throttle body, injectors, ETS and a few other bits are different.
I think unless you have access to the program to make the map that it will take a lot of ingenuity to make it work.

The part numbers of the MAP, IAT, and ET are all different (at least compared to 2007 Touring bikes).  The BT's have a 1 piece TB and manifold, while the Sporty has a separate TB and manifold (like the older style BT's had I believe).  Also, the Sporty uses a MAP-T sensor (MAP and IAT in one sensor), while the BT has a separate MAP and IAT.  Also the BT has the IAT right next to the air cleaner (the best I can tell from the pictures in the parts book).  The Sportster's MAP-T is where the BT's MAP sensor is behind the throttle plate.

And as Rufus pointed out the ET sensor on the BT's and Sportsters are in different locations.  The BT's is on the side of the front cylinder head, while the Sportsters is buried right on top of the rear combustion chamber.

FWIW, the Crank Position Sensors are identical...and the ECM PN's listed are identical (although it would appear the ones actually going on the bikes differ).

Interestingly, the 2007 Electrical Diagnostic Manual for the Sporty and the EDM for the 2007 Touring bikes show identical resistances/voltages for both the IAT and the ET.  They were identical charts.  I'm guessing one of them is wrong (the Sportsters?).

Ingenuity I got...skills and knowledge seems to be what I'm missing. 

[Scotty]

Even though the senors have the same readout for testing I wonder how differently the maps inteprert the data it  receives.
I know the Thundermax would alway give a temperature warning code on the Sportster until they worked out that they just basically ran hotter where the sensor was positioned.
Good luck with it and keep us up to date with how you are going.

[sportytrace]

Even though the senors have the same readout for testing I wonder how differently the maps inteprert the data it  receives.
I know the Thundermax would alway give a temperature warning code on the Sportster until they worked out that they just basically ran hotter where the sensor was positioned.
Good luck with it and keep us up to date with how you are going.

Scotty, what you are saying seems to make sense with respect the manuals giving the same ohms for the BT and Sporty ET sensors. But I guess from the readings posted I'd expect the trend for the temp to be the other way round. As you said with the Thundermax, it threw an error code as it was interpreting that it was running hotter. Yet the temps reported above with the BT ECM suggests it is interpreting the temps as much cooler.

I have to say after being gung-ho and excited about the TTS and the idea of having a go at tuning my bike myself I'm now becoming rather reluctant to try the V-tune without the safeguard of knock sensing. I guess it comes down to not being willing to put my full trust in my own ears to detect knock. Knowing I don't have the safeguard I'd just end up constructing a very safe map that lacked power and fuel economy.   (Or I could just go with canned or get someone else to tune which defeats the attraction I had for DIY)

[Scotty]

With the TTS it is still going to better than a canned map even if you followed HD's recipe because the fuel we use in OZ is different.
Having said that you will know when it is knocking or pinging because it is a very distinctive sound and you can also look at the plugs as well.
Sometimes increasing the timing till it knocks then backing off 3 degrees is not the answer to a sweet running bike