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Still Having Surging Issues - HELP !!

Started by Fritzables, September 04, 2019, 03:18:00 AM

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Fritzables

Hi All,

I still continue to have issues with my tunes.
Generally the tune is good and the bike performs very well above 2,000 RPM.

But I continually have problems with 'part' throttle 'little load' around 1,500 RPM where the result is a surging bike in traffic, which makes the bike difficult to ride unless ya keep the gear box on the lower gears.

I have been adjusting the EGR Tables thinking that this may help my problem, but sadly no. In fact I think I may have gone too far on the Front.

I believe the Rear Cylinder is reasonably happy but I don't see that in the Front.
The Idle is Lean, the Mid-Range is lean.

I have gathered soo much data in the hope it will point me in the right direction. I have most of the Map as being Closed Loop.

So, can someone take a look at what I have attached and give me a shove down the right path.

About the bike:

2017 Fat Boy
110 Kit with 10.2 Pistons
Bassani 2-1 Exhaust
SE-CNC Ported Heads
SE-585 Cams
Standard Injectors
TTS Tuner

[attach=0]

https://www.dropbox.com/s/h5d3qci35q2k9xl/CSV%20Files.zip?dl=0
https://www.dropbox.com/s/wb076n9foq21uvu/Data%20Files.zip?dl=0



Pete

kd

1500 rpm is barely above idle.  I don't think it's reasonable to expect it to be smooth and soft with the engine specs you list.  Keep it above 2000.
KD

rbabos

September 04, 2019, 05:51:57 AM #2 Last Edit: September 04, 2019, 06:03:19 AM by rbabos
Drop the timing in that area. -2 for starters or more depending where you are now in the steady state/rpm kpa range. My  113+120 would buck and jump like a bastard until I did that. I think I ended up at a 18-20 in the 1500- idle to make it smooth. Cover the decel kpa area in those rpms also with same settings.  I'm seeing what looks like 27 degrees and that's just plain asking it to surge. Also, the closer the mixture is to perfect as in 14.7 the worse it will behave, so I'd fatten that area a tad as well. Keep in mind, I'm not a tuner other then my personal stuff but usually have decent success. My advice might be questioned, is what I'm saying. :wink:
Ron

remington007

Try taking those areas out of closed loop. Set the main table 13.9 to 14.1 and see if that helps.

BVHOG

Quote from: kd on September 04, 2019, 05:31:40 AM
1500 rpm is barely above idle.  I don't think it's reasonable to expect it to be smooth and soft with the engine specs you list.  Keep it above 2000.

Bingo!!!!  You gave low gears, use them and do your crankshaft a favor
If you don't have a sense of humor you probably have no sense at all.

Fritzables

Thanks Guys,    All noted with respect to the timing. I'll put it back to what it was originally which was about 20 from memory.

It would be nice to run the entire area in Closed Loop, but I guess, to make it behave and bring the riding RPM up a tad.

Thanks again.

jjdalynh

Quote from: Fritzables on September 05, 2019, 12:17:41 AM
Thanks Guys,    All noted with respect to the timing. I'll put it back to what it was originally which was about 20 from memory.

It would be nice to run the entire area in Closed Loop, but I guess, to make it behave and bring the riding RPM up a tad.

Thanks again.

timing increased in that low rpm area by 7-10 degrees from the map yours is based on, which looks pretty much the same as what you've spec'd.....  Why the increase in timing?  I'm also curious why you have nearly all the Lambda table closed loop with the same middle-of-the-road lambda value?  Seems like you would want a bit more cooling effect over 3500rpm....    If you want to return the whole spark table back to it's more retarded original values, just click the upper left corner where it says RPM to highlight the whole table and then click 'set to original'.

Pete_Vit

Quote from: BVHOG on September 04, 2019, 10:03:32 AM
Quote from: kd on September 04, 2019, 05:31:40 AM
1500 rpm is barely above idle.  I don't think it's reasonable to expect it to be smooth and soft with the engine specs you list.  Keep it above 2000.

Bingo!!!!  You gave low gears, use them and do your crankshaft a favor
:agree: my Evo with a mild cam doesn't like 2G let alone 1.5G,  my ride is tuned for cruising not idling  :potstir:
93 XLH1200 - 96 FXSTS - 2010 Ultra Glide Classic
www.facebook.com/harleypartsch

Fritzables

Just a quick update folks....

Bought the timing back what the original DBC600-01-A0 which is 14 BTDC at Idle then use Open Loop around around Idle and up to 1,500 RPM.
The best is a totally different bike indeed.  No more surging is occurring.

But two observations - the bike off the lights is a lot more sluggish and the Engine Temps are a lot higher.

I will give it another 2 Degrees in the hope it sharpens the bike up and cools the engine, without going back to the surging stage.

rbabos

14 is too low. Find a good mid point in the timing that gives both surge reduction and decent pull. Likely 18-20 would be in the ball park. Remember, too rich will make it doggy too and I'd be inclined to close loop and autotune the new timing in those areas as well before going open loop. Might not have too, so only open loop as a last resort. Take my advice with a grain of salt, but I have my v rod in closed loop all the way from idle to 6k. I have one sweet running engine even though the experts say nothing below 3k in closed loop. I did try open at one point but found it not as good overall, every day.
Ron

Fritzables

Thanks Ron, Got the Idle at 0.960 which should be rich enough and don't believe it's too rich to cause the slug it is now.
Interesting why Steve chose 14 as a default in the map ?!?

Pete

rbabos

Quote from: Fritzables on September 07, 2019, 01:20:33 PM
Thanks Ron, Got the Idle at 0.960 which should be rich enough and don't believe it's too rich to cause the slug it is now.
Interesting why Steve chose 14 as a default in the map ?!?

Pete
14 is the unmodified base cal. I'm seeing the tune in that area quite a bit higher. If you have surging in a specific rpm and kpa range, work that area only. This way, any kpa just to the right will remain untouched and have normal throttle response. Logging, is best to find where to adjust. If you make any changes in the idle area of timing, the close throttle tables will need to follow the change. Likely no need as any changes for surging will be at different rpms. Steve would be a better source of info. I'm just passing on what I've found regarding surging.
Ron