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;!pstwhore Why would the VE for the front cylinder be different at the same time verses the rear cylinder. Wouldn't that in effect make the two cylinders work against each other?

On the SERT Calibration tables for the E version it lists for example:
Front Cylinder VE 59.0 from 500 rpm to 2000 rpm and 53.5 to 3000.
Rear Cylinder VE 75.0 from 500 to 1250 rpm and 79.0 from 1500 to 2000?
I understand that this is in percent but 20% is what I would refer to as a large difference.

Spark advance shows 30* front with rpm of 2000 and Map of 15, while the rear cylinder is showing 23* under same rpm and Map.

It's giving the rear cylinder with a higher VE more spark advance than the front cylinder showing the 20% less VE less spark advance????

Wouldn't it be more productive of the power output of the engine if the numbers were more inclined to be equal of each other, whereas the engine would not be working against itself or am I looking too deep?
 

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It has to do with the 45 degree configuration of the engine. The timing between the cylinder firings is 315 degrees and 405 degrees. At lower rpm's there is a longer delay on the 405 degree difference and this can effect the VE.
 

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Like what Springer says, plus the induction system isn't perfectly cleaved, the rear cylinder tends to run at a higher temp than the front, pipes can have an effect on one cylinder more than the other and you just plain need to trim the 2 cylinders independently by using an AFR sniffer in each pipe to trim the cylinders to each other on a dyno.
 

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For you guys with SERT knowledge

The VE printout on my bike shows both cylingers exactly the same. I was thinking this must be wrong since the rear cylinder will have different tuning due to the heat. I have slight sputter at steady throttle @2500 rpm feels like it is in one cylinder . When I changed pipes I noticed the front exhaust port was light grey, no carbon residue at all. The SERT tuner @ the dealership said nothing wrong. I think there is. If I understand about the SERT correctly, the AFR setting does both cylinders, then they are individually tuned using the VE settings. Help.
 

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Mile Hi said:
The VE printout on my bike shows both cylingers exactly the same. I was thinking this must be wrong since the rear cylinder will have different tuning due to the heat. I have slight sputter at steady throttle @2500 rpm feels like it is in one cylinder . When I changed pipes I noticed the front exhaust port was light grey, no carbon residue at all. The SERT tuner @ the dealership said nothing wrong. I think there is. If I understand about the SERT correctly, the AFR setting does both cylinders, then they are individually tuned using the VE settings. Help.
You are correct in assuming that the chances of the 2 cylinders needing exactly the same VE tables is ZERO! If I had to guess, your slight sputter is probably the front cylinder going too lean at cruise load. This is what we found in my setup during load brake tuning on the dyno last week.

Generally speaking(and I'm sure there will be exceptions) and this depends on pipes(amount of scavenging) and other variables but the front cylinder tends to run lean and the rear tends to run rich. The only way to really fix this is by trimming the cylinders to each other by individually adjusting the VE tables to the correct AFR under load and WOT on the dyno. The spark advance is then done also while noting knock and adjusting fuel and spark accordingly. It is quite an involved process to "really" tune the motor and do it correctly. I've noticed that when the cylinders are tuned correctly, my motor runs noticeably smoother, even though there is a set of 37G cams and 1.67 ratio rockers inside. The balance or equilibrium of power is unmistakeable.

If you really interested in getting the most out of your motor, the best thing you can do is to find a engine specialist that really knows how to use a dyno and tune it correctly for you. And don't expect this to be cheap to do! It takes time to methodically optimize everything.

Are you running a non-stock build of some sort?
 

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'05 FXDI, 95 w/6G, J.E.T. heads, hi comp flattops, stock headers w/Rush 2" slip ons. The copies of the VE tables look exactly alike but are labeled front & rear. It ran fine after the initial SERT dyno tune, but started this sputter stuff later. This is my first twin cam and first fuel injection, so trying to learn this stuff. Only place to get SERT tuned is at dealerships in Denver area, so they do the sop of "nothing wrong" and "that's normal".
 

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Who tuned it?

My nephew(VTF user Thunder90) lives in Littleton and just did a build that needs tuning. I think he said he was going to go to Rocky Mountain Harley in Littleton after he interviewed the dyno guy there. But Thunder90 has carbed Twinkie, no SERT, nevertheless he was impressed by the main dyno guy there. Somebody out there has to be SERT competent.
 

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Freedom HD did the build and tune. I have a written warrenty (!) on the mods and tune from them, so I gotta make them live up to it. I have heard good things about Rocky Mt HD. But they are miles away and hard to get to (traffic). So just to clarify: if tuned correctly, the VE tables should be different for the front and rear cyclinder? This makes carb rejetting seem so simple.
 

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Mile Hi said:
So just to clarify: if tuned correctly, the VE tables should be different for the front and rear cyclinder?
yes, if the time is really put into running the AFR sniffer for each cylinder separately. Thats how the cylinders should be trimmed to each other.
 

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Discussion Starter · #11 ·
Sputter

Milehigh,
I believe that I have the same "Sputter". I've got an 06 ultra with 95 bb stg 2 with 203's, SE A/C and Rinehart true duals. My sputter occurs at 1800 to 2000 rpm after reaching a velocity speed and holding that speed either in 3rd or 4th gear. May also do it in 5th but don't notice it and I'm not usually doing that low of an rpm in 5th. Only one skip or sputter and it is not a repetitive skip, just one miss, as if the map is being read in a different fuel or ignition cell. I'm kinda leaning to the injector (8* injector and programming) as the main culprit. Am having the dealer install the 25* units and reprogramming in the next couple of weeks. Will let all know if it helps out. Will be doing some tuning after that with my SERT.
:beatdh:
 

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I can't see any reason why the VE tables would be identical. I've got an 05 SERT disc and all the canned programs have big differences on the Frt and Rr VE tables. I know everyone complains about the canned maps for a custom build, but I would look at them as a starting point. Your build is roughly similiar, I know not real close but in the same general ballpark, as the 1550 stage II build. Flat tops, Perf heads, mild cam... Looking at the canned map for that HD combo, the Frt and Rr VE tables for that are completely different.

I used a very slightly modified Stage 1 canned map, just some minor richening up tweeks and decel enleanment tweeks, and it runs great. The VE tables look completely different, I can't imagine it would be tuned anywhere near as good if I just equaled both of them. I think the HD engineers make those tables unique for a reason, and your tuner has some splainin to do.

For shits and grins, I'd pop in that Stage II canned SERT map and see how it runs. As long as you've got your current map saved so you could put it right back in.
 

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I made a mistake; it's the 3d graph

I said tables, but what I got were the 3d graphs instead, which are identical for both cyclinders. I will hit them up for the tables tomorrow. So, for those who would know, should the 3d graphs be different for front & rear. Appreciate any help.
 

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Mile Hi said:
I said tables, but what I got were the 3d graphs instead, which are identical for both cyclinders. I will hit them up for the tables tomorrow. So, for those who would know, should the 3d graphs be different for front & rear. Appreciate any help.
IMO, yes the graphs should be different with a Dyna's dual exhaust system.

From the SERT's 127HB025-BO.MT6 Softail/Dyna Map:



HTH's

:cheers:
 

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Help me interpret this

Got copies of the actural VE tables from the dealer. These show both cylinders the same until 40% throttle, 1750 rpm. At 15%, 2500 rpm they show 94.5 , at 20% its 101.5, at 30 % its 89.5. It has at the bottom of the page: Ca #10--127EV100-B0.MT6 Application 2005 Touring and FLSTSI Configuration 1550 Stage 2. Did they just put in a canned map and adjust from there? I have a sputter at 2500 steady throttle. Its gotta be the front cyclinder: I looked at the exhaust port when I changed the pipes and the front was light grey, no carbon. Rear looked normal. Plus it doesn't have the hesitation and surging that lean carbed motors do. I need to know if this is a can map before I go back and have a serious heart to heart with the service manager. Any help appreciated.
 

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They started with a canned map and from the cells you described, it appears they modified the map.

Calibration #10: 2002 – 2005 Touring, 2001 – 2003 FLSTSi and 2005 FLSTSCi
Configuration: 1550 Stage 2
File Name: 105EV100-D0.MT6, 127EV100-B0.MT6
Components:
• SE Air Cleaner and Breather Kit P/N 29440-99B
• SE 1550 Big Bore Cylinders P/N 16546-99 or 16549-99
• SE 1550 Flat Top Pistons P/N 22851-99A
• SE 203 Cams P/N 25937-99B
• SE Performance Touring Mufflers P/N 65115-98B or 65116-98A

VE front cylinder

74.0 80.0 78.0 86.0 90.0 92.0 93.0 93.0 93.0
78.0 80.0 78.0 86.0 94.0 94.0 93.0 93.0 93.0
80.0 86.0 92.0 88.0 92.0 99.0 93.0 93.0 93.0
85.0 91.0 92.0 88.0 92.0 99.0 97.0 97.0 97.0
80.0 90.0 90.0 90.0 86.0 85.0 85.0 85.0 85.0
80.0 89.0 90.0 90.0 88.0 82.0 84.0 84.0 84.0
74.0 89.0 90.0 90.0 90.0 84.0 84.0 84.0 84.0
75.0 89.0 96.0 95.0 99.0 96.0 96.0 94.0 94.0
91.0 89.0 99.0 101.0 100.0 100.0 100.0 100.0 100.0
82.0 89.0 106.0 105.0 106.0 106.0 103.0 103.0 103.0
89.0 94.0 114.0 111.0 104.0 99.0 99.0 99.0 99.0
65.0 92.0 102.0 104.0 95.0 92.0 92.0 96.0 96.0
55.0 92.0 105.0 104.0 102.0 90.0 90.0 96.0 96.0
55.0 92.0 107.0 99.0 102.0 92.0 92.0 92.0 92.0
55.0 92.0 107.0 98.0 95.0 92.0 92.0 92.0 92.0
55.0 92.0 107.0 98.0 95.0 96.0 94.0 94.0 94.0
73.5 92.0 107.0 98.0 95.0 96.0 94.0 92.0 92.0
73.5 92.0 107.0 98.0 95.0 96.0 94.0 92.0 92.0
73.5 92.0 107.0 98.0 95.0 96.0 94.0 92.0 92.0


VE rear cylinder

62.0 71.0 85.0 79.0 85.0 90.0 93.0 93.0 93.0
62.0 71.0 85.0 79.0 85.0 90.0 93.0 93.0 93.0
63.0 75.0 85.0 81.0 85.0 90.0 93.0 93.0 93.0
67.0 76.0 87.0 95.0 94.0 87.0 93.0 93.0 93.0
65.0 70.0 84.0 88.0 94.0 85.0 85.0 85.0 85.0
62.0 70.0 80.0 88.0 94.0 84.0 84.0 84.0 84.0
62.0 70.0 80.0 88.0 96.0 88.0 83.0 83.0 83.0
61.0 74.0 82.0 88.0 104.0 102.0 88.0 86.0 86.0
62.0 74.0 82.0 88.0 100.0 102.0 88.0 88.0 88.0
60.0 74.0 82.0 89.0 100.0 100.0 90.0 90.0 88.0
60.0 71.0 85.0 89.0 99.0 100.0 96.0 96.0 96.0
60.0 71.0 85.0 87.0 102.0 115.0 102.0 102.0 102.0
60.0 71.0 85.0 87.0 102.0 105.0 104.0 104.0 104.0
60.0 71.0 85.0 87.0 102.0 105.0 92.0 92.0 98.0
60.0 71.0 85.0 87.0 102.0 105.0 92.0 90.0 90.0
60.0 71.0 85.0 87.0 102.0 105.0 92.0 90.0 90.0
68.0 78.0 85.0 100.0 102.0 105.0 92.0 100.0 100.0
68.0 78.0 85.0 100.0 102.0 105.0 92.0 100.0 100.0
68.0 78.0 85.0 100.0 102.0 105.0 92.0 100.0 100.0
 

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Mile Hi said:
Got copies of the actural VE tables from the dealer. These show both cylinders the same until 40% throttle, 1750 rpm. At 15%, 2500 rpm they show 94.5 , at 20% its 101.5, at 30 % its 89.5. It has at the bottom of the page: Ca #10--127EV100-B0.MT6 Application 2005 Touring and FLSTSI Configuration 1550 Stage 2. Did they just put in a canned map and adjust from there? I have a sputter at 2500 steady throttle. Its gotta be the front cyclinder: I looked at the exhaust port when I changed the pipes and the front was light grey, no carbon. Rear looked normal. Plus it doesn't have the hesitation and surging that lean carbed motors do. I need to know if this is a can map before I go back and have a serious heart to heart with the service manager. Any help appreciated.
Mile Hi:

IMO, if they used the 127EV100-BO.MT6 file as the base for your DYNA, they definitely got off on the wrong foot!

It is a Touring/FLSTSI base map and a very poor one at that when compared to a similar Softail/Dyna Map!

Regardless of what's in the map's File Comments, the Part No is imbedded:



What's the big difference between the Touring line and the Dyna? THE EXHAUST!

Take a look at the VE and Spark Graphs in a comparable canned Dyna Map, and notice how smooth they are.

Just my -2$en#e-
 

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thanks guys. Looks like the service manager and I are going to spend some quality time together. Now, since it's in the mid 50's, I'm going to take my nephew's Victory for a ride.
 

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They should have started with 127HD019 and fine tuned it from there. That's the Softail/Dyna stage II map.

I'd buy a couple sets of spark plugs and do some plug checks before and after they fix their screw up. The pipe/port appearance can be an indicator, but the spark plug, your ear, nose, butt o meter, and dyno are the real tests.

Especially the plugs. Dialed in right, they should look very similiar, and have all the telltales of correct timing, fuel mixture, temp ... That's a whole other story on how to read a plug, there is a ton of good info on the web.

A screwed up map one plug may look ashy whitish, one black, and it runs like crap. Get it right and the insulator will be a little brownish/tannish, the fire ring (end of the threads) will be evenly dark, and the ground strap will be discolored to the right point. That you have to look at example pics to get an idea how to read the ground strap. And it will run smooth, not stink, backfire, or other bad habits. That should be a real good torque set up with that cam, no reason it shouldn't be able to be tuned to run smooth and pull hard.
 
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