Tuning a SERT with the WEGO2??

[AirGlider]

GP:
Will the cable reach the 88+ unit or do you have an extension? Need to know if I need to order an extension cable with my + kit.

Thanks,

Karl

[GPO03FatBoy]

Originally Posted by AirGlider

GP:
Will the cable reach the 88+ unit or do you have an extension? Need to know if I need to order an extension cable with my + kit.

Thanks,

Karl

Karl - No extension cable is required to use the 88+ on the bike. (I'll try to post a pic later.) The 88+ setup has both the Twinscan interface box (similar in appearance to the SERT key) and the WEGO. The Twinscan 88+ interface has a Deutsch plug to connect to the bike. The WEGO II has a sensor output wire to connect to the Twinscan 88+ interface, power leads, and an input cable to connect to the O2 sensor. The stock leads look long enough to allow O2 sensor positioning anywhere from the front of the bike (bung on pipe) to the rear of the tailpipe (probe). Aside from special installs trying to do real fancy cable routing, there should be enough cable with the kit.

The one cable length issue could be connecting the Twinscan 88+ interface to your PC. If you can set a laptop on the bike or a table right next to it, you can plug the 88+ interface right into your serial port. Otherwise, you may want a serial cable to let you move the PC around a bit near the bike.

[GPO03FatBoy]

Originally Posted by fl_799

This is real good info. I've been considering taking the 88+ plunge for sert tuning. You are the only guys who can talk the 'jive' so I'll get to the point.

My dilemma is the 06 Dyna closed loop setting. I'm planning on getting all the VE data adjustment through the SERT 13.2:1 method and use the factory o2 sensor exhaust bungs for the wide band O2 doing each cylinder one at a time. From there, I'm going to copy/paste back my tweeked current A/F table (closed loop portion is scaled back to actual cruise portion of the map) and tune in the closed loop mode with the homemade exhaust sniffer. There is a setting (closed loop O2 Bias) that has limited adjustment to richen up the closed loop cells lower then 14.6:1. I'd be gunning for 14.2:1 in all closed loop areas. I have been tinkering with this but have no idea what the bias settings are doing. My homebrew map is pretty good but this would put it in the bullseye. How does this 'plan' sound to those who have used the twin scan 88+. Sounds like a dream come true for the home tuner!

I'm working with a SERT on an 03, but in concept your approach sounds right. The closed loop system will only handle small changes around the base map. If you optimize your tuning open loop, and then kick back in the closed loop mode you should be there. Correcting the VE tables is the easy part though. Setting up a good base A/F table without the ability to analyze the gas burn to optimize efficiency is the hard part. Short of a lot of time on the street or dyno, or the ability to do a full exhaust gas analysis, I'd plan on tweaking the VE tables and then using one of the canned A/F tables. FWIW.

You might want to take a look at how the others are tuning the TCFI systems.

[fl_799]

Thanks for the affermation GP,

Yeah, from the looks of it, populating the VE tables should be a piece of cake. Just drive the bike and log then edit via the SERT. Hard part done! My current modded maps A/F and closed loop ratio looks very sane and solid all through the map. My current map's closed loop is scaled back to a smaller portion where the stock map covers about 85 percent of the map up to 90 MAP (crazy I know). When the VE's line up, I'd probably lean out the 100 map a few percent but otherwise, it would be all set. Otherwise, this whole thing is a blast from the past. I thought I was done with Speed Density systems in the 80's.....

Overall, I would be gunning for 14.2-14.3 in the scaled back closed loop mode for cruise economy right where is makes sense. It's just that we just don't know what the settings on the closed loop bias table is doing 'on the street'. I know that control is extremely limited but it would be nice to know for sure.

Originally Posted by GPO03FatBoy

I'm working with a SERT on an 03, but in concept your approach sounds right. The closed loop system will only handle small changes around the base map. If you optimize your tuning open loop, and then kick back in the closed loop mode you should be there. Correcting the VE tables is the easy part though. Setting up a good base A/F table without the ability to analyze the gas burn to optimize efficiency is the hard part. Short of a lot of time on the street or dyno, or the ability to do a full exhaust gas anlysis, I'd plan on tweaking the VE tables and then using one of the canned A/F tables. FWIW.

You might want to take a look at how the others are tuning the TCFI systems.

[BVBOB]

Originally Posted by fl_799

This is real good info. I've been considering taking the 88+ plunge for sert tuning. You are the only guys who can talk the 'jive' so I'll get to the point.

My dilemma is the 06 Dyna closed loop setting. I'm planning on getting all the VE data adjustment through the SERT 13.2:1 method and use the factory o2 sensor exhaust bungs for the wide band O2 doing each cylinder one at a time. From there, I'm going to copy/paste back my tweeked current A/F table (closed loop portion is scaled back to actual cruise portion of the map) and tune in the closed loop mode with the homemade exhaust sniffer. There is a setting (closed loop O2 Bias) that has limited adjustment to richen up the closed loop cells lower then 14.6:1. I'd be gunning for 14.2:1 in all closed loop areas. I have been tinkering with this but have no idea what the bias settings are doing. My homebrew map is pretty good but this would put it in the bullseye. How does this 'plan' sound to those who have used the twin scan 88+. Sounds like a dream come true for the home tuner!

I see you are planning the very same thing as I am, just wondering if you researched the if the threads are the same on the wide band WEGO 02sensor compared to the stock 06 Dyna 02 sensor.I have been studying some of the closed loop maps on my SERT G disc and see what you are talking about when you say they run the 02 sensors on a good portion of the map on some files. I think this system with the stock 02 sensors could ultimately be better when incorporated instead of just disabled.

[fl_799]

Thanks for the reply. I'm researching if the bosch wideband will work in the factory bungs but I've been told by a few people that the threads are the same. I guess I'll find out! Not worried, I'm pretty creative!

Here is an image of my modded A/F table. As you can see, I scaled back the closed loop operation to cruise only areas. In addition, I have added some fuel to the closed loop bias table. I have zero drivability issues, no popping, no lean surging, excellent economy, and excellent WOT performace. Bike is running pretty good! But In the interest of tinkering, I think I could do some clean up, match up those VE's a bit tighter and dial in the 100 map a bit leaner to 13-13.2 for max HP and Torque with the WEGO/TC88+. I not going to go any furthur without having the VE's as accurate as it can be. Some of the guys running the SERT can play russian roulette and flag their tables to 13.7 across the board but I won't be buying any of those bikes anytime soon.

Take a look at this. Through alot of trial and error on the road (NOT on a dyno), I managed to find very happy compromise for the closed loop operation. Unless you are cruising, you 'aint using it just as it should be. The transistions between open loop and closed loop are seamless. To the lurkers reading this, here's the future for all closed loop HD's in '07. This is why to tune your bike properly, the sert is the only game in town unless you go with an entirely new wideband system.

[BVBOB]

Originally Posted by fl_799

Thanks for the reply. I'm researching if the bosch wideband will work in the factory bungs but I've been told by a few people that the threads are the same. I guess I'll find out! Not worried, I'm pretty creative!

Here is an image of my modded A/F table. As you can see, I scaled back the closed loop operation to cruise only areas. In addition, I have added some fuel to the closed loop bias table. I have zero drivability issues, no popping, no lean surging, excellent economy, and excellent WOT performace. Bike is running pretty good! But In the interest of tinkering, I think I could do some clean up, match up those VE's a bit tighter and dial in the 100 map a bit leaner to 13-13.2 for max HP and Torque with the WEGO/TC88+. I not going to go any furthur without having the VE's as accurate as it can be. Some of the guys running the SERT can play russian roulette and flag their tables to 13.7 across the board but I won't be buying any of those bikes anytime soon.

Take a look at this. Through alot of trial and error on the road (NOT on a dyno), I managed to find very happy compromise for the closed loop operation. Unless you are cruising, you 'aint using it just as it should be. The transistions between open loop and closed loop are seamless. To the lurkers reading this, here's the future for all closed loop HD's in '07. This is why to tune your bike properly, the sert is the only game in town unless you go with an entirely new wideband system.

couldn't get the pic of your map to come up, but anyways I ordered my twin scan 88 Wego II package yesterday, they said a short delay in backorder, a few days. They do discount to V-twin forum menbers, Mine cost $345.00 Cheaper than a good dyno tune and can be used on several bikes plus the ability to scan for codes etc. Forgot to order an extra bung for the sniffer setup. I would like to try the sniffer on my 05 Ultra with the existing dfo tune and see how close it really is.

[LAF]

Guys I have asked this before and don't think I got an answer but WHAT does VE represent on the SERT?

I run the TCFI but I think with a good sert tuner, and knowing what VE correlates to on the TCFI will help me in getting a better understanding from the more experienced SERT tuners on this forum.

One time someone converted some TCFI data to SERT VE data but I don't remember (half-heimers) who it was.

Am I off base in this thought process?

[GPO03FatBoy]

Originally Posted by LAF

Guys I have asked this before and don't think I got an answer but WHAT does VE represent on the SERT?

I run the TCFI but I think with a good sert tuner, and knowing what VE correlates to on the TCFI will help me in getting a better understanding from the more experienced SERT tuners on this forum.

One time someone converted some TCFI data to SERT VE data but I don't remember (half-heimers) who it was.

Am I off base in this thought process?

To quote HD -

"VE represents Volumetric Efficiency. VE is the percentage rating of how much air is flowing through the engine while running as compared to its theoretical capacity. For example, an engine with a displacement of 88-cubic inches running at 5600 rpm at full throttle has a theoretical airflow capacity of 100% when it flows about 143-cubic feet of air per minute, (cfm). If the same engine flows 107cfm at 5600 rpm it would have a VE of about 75%. The ECM of the ESPFI system uses the VE values to calculate the amount of fuel that it delivers."

Effectively, it is the individual fuel adjustment for each cylinder, based on the A/F table.

[GPO03FatBoy]

I think of the 13.2 VE adjustment, based on the WEGO, as the individual calibration of the A/F map to an individual engine. Once the 13.2 tune is done, the numbers in the A/F map should be close to absolute, vice relative, changes. Also, once the 13.2 tune is done for both cylinders, adjustments to the A/F table should affect the two cylinders more equally (at least in theory).

[GPO03FatBoy]

Well I just did a half dozen runs on the bike with the WEGO II/88+ setup (three per cyl). I have to say that the Twinscan software makes tuning the VE tables a snap. The HD Data mode should have the Twinscan functionality for reading the AFR and calculating the VE corrections.

All my runs were with varying throttle and rpm. I didn't do any WOT or rapid accel runs. What that gave me was a nicely corrected 13.2 table for everything under 30% throttle.

I had started with SERT Cal 17 (which is for a HTCC 95). My bike is a 98 build with Andrews 37G cams, mildly ported heads, a Stage I intake, and SE II slip ons.

What I found interesting was that while all the lower RPM cells for throttle below 10%, were quite lean; the mid RPM cells for throttle from 20-30% were actually rich.

The other thing I found - no surprise, is that you can burn a lot of gas running a flat 13.2 AFR! I think gas mileage at 13.2 must be about 25 mpg.

Also, I guess I won't be afraid to hit redline any more! Running fully through the tables I spent more time at 6k RPM in the past two days, than the previous two years. LOL

At the moment I have a nicely corrected SERT map for all working RPMs at 30% throttle and below. I guess the next step is to do some WOT runs from 2k RPM. It'll be interesting to see what the A/F ration looks like for those.

[AirGlider]

Keep us informed. I am awaiting delivery of my 88+. Hopefully sometime this coming week.

[GPO03FatBoy]

Some thoughts on tuning the SERT with a WEGO/88+ setup and Twinscan software.

First, the Twinscan software is great for tuning the O2. Used with the WEGO/88+ hardware you do not have to lug around a laptop like with the SE Data package (though you may want to), and the Twinscan software produces a nice clean O2 correction table for the VE adjustment.

Second, if you don’t want to install bungs on your exhaust, you’ll want to make/buy a exhaust probe for the O2 sensor. Everything you do to tune, has to be done twice, since you tune the cylinders separately. Also, the probe requires about a 7/16” opening straight through your exhaust baffle, to get it inserted deep enough to avoid significant reversion problems.

Also, when logging engine data and A/F data from the WEGO, the 88+ will hold about 12-13 minutes of data at one sample/0.5 sec. When doing WOT runs to adjust the VE at say 50%, 75%, and 100% throttle I found that a sampling rate of 0.25 sec worked well. A 3rd gear run from 2k rpm to 6200 rpm at 100% throttle took me about 9 seconds. Sampling at 0.25 sec gave me sufficient data to make corrections to the fuel mixture and spark. At 0.25 sec you can hold about 6 minutes of data in the 88+. Since I did not have a track to use, I carried a laptop in a backpack with the Twinscan software up and running. I would do a 2k to redline run, then wind it down and download the data. Then I’d name and store the file, clear the 88+ buffer and do another run changing either gear or throttle position, until I had collected all the data that I wanted. If you have a track, you could get by without carrying the PC. I used a straight interstate stretch. Also, keep in mind that 6200 rpm on stock gearing for an 03 is just over 90 mph. You may only hit that for a few seconds, but you don’t want the local constabulary around during those few sec.

I used either a 0.75 or 1.0 sampling rate to do low manifold air pressure (Map), varying rpm runs. At 1.0 sec I had about 25 minutes of data time. That meant I rolled out and held a rpm for about 6 seconds (to get 5 consecutive data points), then bumped up the rpm by 500 and held for 6 more seconds. I worked from 1k to redline in 1st, 2nd, 3rd, most of 4th, and part of 5th. Top end speeds prevented me from getting high rpm data in these low Map runs. Since I live just off an inter-state, in 25 minutes I could collect a full run of data, and get home to download it before the buffer was over-written. The long sampling period ensured multiple consecutive data points, and enough time to get home without having to carry a PC. Getting multiple consecutive data points ensures you don’t have problems with spurious data in building the VE corrections.

Once I had collected all of my data I found that I had built kind of a football shaped correction table for the low Map cells. At low Map you won’t get data at high rpm and the lowest Map readings, or below about 3k rpm at about 30 Map. You’ll get a nice cluster of data through typical riding ranges across the gears. For the higher Map readings, you will pretty much have straight line vertical correction strips at whatever throttle position you hold. EG, a 100% throttle run will build a straight line VE correction down the 100 column. If you wanted to correct all of the VE or spark data above say a Map of 40, you would have to do a full range rpm run at the corresponding throttle position. For me, a 50%, 75%, and 100% throttle run was more than sufficient.

Also for me, building the VE corrections against a 13.2 A/F table made the most sense. With the Twinscan software you can set the 13.2 value and turn the screen on to the display correction setting, and than just adjust the VE per the correction numbers. Trying to correct a full VE table with varying A/F settings would be a pita. After you’ve normalize the VEs, you can just plug you’re A/F table settings back in and tweak them as you like for economy or acceleration.

What worked for me was to build the corrected VE tables against a 13.2 A/F table. Then, I restored my A/F table to a realistic one and collected more data (particularly WOT data) to correct the spark tables and tweak the A/F. I collected the 13.2 data with anti-knock off. I did my re-check with the actual A/F table, with anti-knock on. I used the knock readings to determine where to adjust spark or tweak fuel. Also, I used the spurious data filtering and 4-5 samples per cell for establishing correction factors for the VE in the low Map region. I turned off the spurious data filtering off, and used either 1-2 samples per cell, or just the graph of the WEGO A/F data, to do the VE corrections in the heavy throttle regions.

I did the tuning in steps. I made a data collection run, analyzed the data, adjusted the SERT map on my laptop using the Twinscan info, loaded the new SERT map back into the ECM, then made another run. I figure, between learning the oddities of the software, being a first -timer, and having to work around family schedules, that I put about 16 hours into riding, analyzing, and reloading the data into the SERT.

So, at the end of all this, what do you have? A strong running, pretty well-tuned bike. Let me caveat all this by saying – I wanted to do this! It was therapy and a learning process. But…….. If you want to know your Tq/HP, you still need a trip to the dyno. And……… based on what you see on the dyno you may want to do more corrections of the ECM Map.

If you figure the time, the cost of the 88+ setup and misc parts/software, the problem with finding good roads to tune on (considering traffic), and the liklihood of bumping in to a trooper right as you redline in 3rd gear, - a few hours on the dyno are a bargain. Also, no matter what, and even if you tuned on a dyno, it’s still just an O2 tuned bike. You would probably really want find a guy who tunes with a Multi-gas dyno to get an optimal tune. And then - my pet peeve - you’ll want to find a tuner who will also give you your SERT map at the end of the tuning session.

So take this for what it’s worth. It was fun and educational. I’m glad I did it. But, tuning yourself is certainly neither the easiest, nor the cheapest, way to get your bike tuned.

[AirGlider]

Great post! I'll be using your guidance to tune my bike once the 88+ arrives. Did you install the O2 bungs or make a sniffer?

[GPO03FatBoy]

Originally Posted by AirGlider

Great post! I'll be using your guidance to tune my bike once the 88+ arrives. Did you install the O2 bungs or make a sniffer?

I put together a sniffer. I'll see if I can pull up a snap of it mounted on the bike, but here is the sniffer just after I put it together.
http://65.38.172.84/forums/showthrea...967#post789967

http://65.38.172.84/forums/showthrea...436#post786436