T-MAX - surging, backfiring, and ping ping ping

[mayor]

Just so we are on the same page - The map rpm is the activation point for the map.  If you fall below the rpm on the map - you revert to the lower rpm map page.  Consenquently as soon as you reach an rpm of the next map higher you start using that map.

yes, I think you and I are reading it the same way. 

[genedjr]

OK - here is the current status:

• I have put on 200+ miles since moving to this map (attched)
• I applied the learned offsets 5 times after various rides
• The surging is very very minor now.  I have a monitor file for this mornings IAD run to 275*
• I still have backfiring, but its very limited and I think Autotune is fixing most of it.  (Though I am not sure what it is doing.)
• I still have pinging noise at about 2400 RPM.  Its still annoying.

Overall I am very pleased with the T-MAX.  I was anticipating serveral "do overs" requiring me to start from scratch.  So far only one "do over" and it was not a complete waste.

My next step is to apply the tuning to the AFR correction vs engine temp as described by Jim in another thread.  I am also thinking about changing the my adjustable pushrods to increase the extension from zero lash from 4 turns to 5 turns (being .178 if the TPI is 28 and .156 if the TPI is 32).  The pinging noise is still there, but much quiter and only when the engine is completely warmed up.

Unfortunately its's supposed to snow today, but hey it will be warm again...

...gene

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[genedjr]

I have about 1000 miles on this map now and applied the learned offsets many times.  I also (about 20 min ago) upgraded the smartlink software.

I still have a few issues:

• I still have the clacking at 2200-2400 rpm in any gear
• I still have massive backfiring under hard deceleration
• MPG is not as good as it could be, but then I am running 13.6 AFR in cruise.

For me I think the next step is to advance the timing more than what Jim provided at low RPM.  I think i can get alot more out of the low end.  Then I think I will up the AFR to get better MPG.

All-in-all its working well.  I really think it can be better and I hope I can rid myself of the backfiring.

...gene

[genedjr]

OK, so I upgraded smart link to 2009.0.5.
Since I do have "Frequent Deceleration Pop" I decided to check that box and auto update the module.

WOW WOW WOW  - very impressive.

While I was only able to get out for about 20 min, I now have ZERO pop or backfire on deceleration.  Even at rev-limit in 1st.
An added benefit is that what very little surging I had seems to now also be gone.

Hopefully the weather out here in Colorado will coorporate tomorrow and I will get a bit of riding in.  But so far I am ecstatic! 

Now I need to look at all the maps and see what changed.
...gene

[tommy g]

Interesting thread, I for one am waiting for your results as I have a Tmax in my back pocket waiting to put on my new scoot come summer time. I took it off my 07 E Glide and am wondering if there are recomendations on when to change out the 02 sensors for new ones. These have about 13,000 miles on the oriiginal wide  bands that came with the Tmax.
Thanks, Thomas

[sprocket99]

On page 148 of the TMax tuning manual it describes how to check the O2 sensors. You can buy new wide band sensors at auto supply stores for much less than from Zippers, and IMO it wouldn't hurt to change them out.

[glens]

That test is only to determine if the sensor/controller can indicate the "free" oxygen in our atmosphere.  It doesn't correlate in any meaningful way to what true 14:1 (or 14.8:1, or 12.8:1, all using unadulterated unleaded gasoline) will actually get reported as while in service.

Bosch themselves are preaching "replace often" regarding all their O2 sensors.  Of course, they do have various intervals for the different types.

The WEGO 4 instructions from DTT say on page three, immediately after instruction to free-air calibrate the sensor while it's hanging in "free" (preferably outside) "air":

"The free air calibration procedure should be performed at reasonable intervals (every 250-500 hours) or whenever the sensor is replaced.  If you cannot get the display to indicate "FA" when the  trimpot is turned full clockwise (sensor in free air), you either have a damaged sensor or very high hydrocarbon levels in your environment."

I had a few manufacturer's documents around here but can't find one in particular now.  It basically said to replace O2 sensors whenever you change your spark plugs.  Also, one in particular said that the Bosch LSU 4.2 would retire at a much quicker pace when subjected to prolonged usage at <0.95 lambda.  Using "straight" gasoline at 14.7:1 for lambda=1, that threshold comes to <13.96:1 AFR (gasoline).  So if you're "cruising" at <14:1, check and/or replace your sensors oftener.

In terms of "when you change your sparkplugs" I'm pretty sure they were talking about automobile, not motorcycle.  Usually, in an automobile the sensors will/can be located in a more relaxed environment regarding temperature and pressure.  Incidentally, these sensors will only be as accurate as they can be when temperature and pressure readings at the sensor are taken into account while in service.

If I were to use these "wide-band" sensors on a Harley, I'd likely consider 18k miles to be "used up".  Especially so if I was contemplating just putting them into service at that "age".

[genedjr]

OK, just cus this is my thread, I am jumping back in.  I will comment on the above later, right now I have a question.

I have updated my map several times and I am working on a map that has GREAT cruise MPG while having lotsa rip for my van-winkle.

While I have riddin this map alot, I was lax on updating.  Right now the map runs fantastic - until about 90mph in 4th - then there is a noticable loss of power.  I used to be able to blast past 120 on flat straight roads, now I cant get to 110.

I know I need to ride it more and update more, but I am interested in genreal thoughts.
(maybe I just need to start over 

...gene

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