Does anyone know how to change Ignition Timing at at specific rpm with ECM Spy ? I need to retard my timing at 2500to3500 rpm , but remain at the stock timing the rest of the map . I am told it can be done , but don't know what page or tab to click on in ECM Spy . Is it in a map some where that I change and then re-burn to Eprom ? I have been working with a guy here in the US that does maps , and my 07 XB9R still has a surging at part throttle at 2500-3500 . I have found if I retard the static Timing a few degrees I can get it to stop , but It looses alot of low end power . I was told to retard it on the timing maps with ECM spy , then return the static timing to stock . I just don't know how to do that . Thankful any help .

Changing the ignition timing is as easy as changing the fuelling...

I was interested that you say the ignition timing needs to be retarded at 2500 to 3500, I think everyone finds it a little fluttery there. I am interested to see if retarding the timing does do that, but I have not had chance to try it...

Anyway, whilst chopping an onion, I was thinking that the optimum ignition timing *could* be estimated from the fuel maps. I think we have gone over this before, but ignition timing is dependant on:

Engine speed (when are we going to start the combustion process to it is most efficient?)
Volumetric efficiency (how much stuff is there to burn / how fast will the flame travel?)
Mixture strength (how fast will the flame travel?)

Of course, we need to add a bit on for knock margin at low speeds and a bit more for the rear cos it is hotter.

Volumetric efficiency is going to be a function of exhaust/intake/valve timing interaction and of course TPS.

In the closed loop area, where you can feel the fluttery effect (mine is not so bad now I have richened up the front cylinder), the mixture strength is fixed (i.e. lambda = 1), so it is down to TPS, exhaust/intake/valve timing interaction and engine speed.

What does this mean? Well, I reckon by drawing a few graphs in Excel from the fuel map data, I reckon you can predict whether the ignition timing is in the right ball park.

Next job is to look at some data....

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08 Specialized Langster

So, looking at the stock ignition map for an 07 XB9R:



The ignition table breakpoints for speed are different to the fuel map, however we are talking about 3000rpm.

Now, I would say, with no further changes:

For increase in speed, you need to increase advance
For increase in TPS, you need more retard
For increase in volumetric efficiency (higher number in fuel map) you need more retard

So, in the 3000rpm column, I think the advance should steadily increase as the TPS decreases, increase as you leave OL WOT (13.2:1) and go into OL (14:1) and then CL (14.7) then reduce (or a reduction in the increase in advance) as you go to OL again (14:1)..

It doesn't do that though... I feel some experiments coming up...

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08 Specialized Langster

A bit more input:

http://www.ecmspy.com/download/gunter/timing.jpg
upper: 2007 XB12, country code 77
lower: 2008 XB12, country code 79, calibration ID: M31EC27Z

http://www.bilder-hochladen.net/files/ccmo-1-jpg.html
unknown country code. calibration ID: M31EC25Y (Source)

http://www.bilder-hochladen.net/files/ccmo-2-jpg.html
unknown country code, calibration ID: M31EC30Z / M31EC311 (currently latest flash) (Source)

Note the new advance in idle section, probably an attempt to fix wandering idle speed.

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"It is often said that before you die your life passes before your eyes. It is in fact true. It's called living."
Terry Pratchett

Yes, we played around with the advance in the olden days, pre-site-crash.

I pushed the advance up until the engine speed stopped increasing and it was a lot more stable. I think I ended up with 10 degrees of advance in the table instead of 0.

Do we know if the 08/09 data has the same idle ignition timing compensation (as a function of engine temp)?

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08 Specialized Langster

Yes:

adv. (°) - TE (°C)
4.0 - 120
6.5 - 60
7.0 - 18
13.0 - 0

But I have never seen that active in any of my logs, althought the system configuration was set up that way. I'm going to give it a try tomorrow.

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"It is often said that before you die your life passes before your eyes. It is in fact true. It's called living."
Terry Pratchett

That would be interesting. I need to resurrect my rig...

I am thinking that I may rescale the ignition timing look-up-table to include the peaks in volumetric efficiency, i.e. on a standard 12, these occur at 1900 and 6000rpm for the front and 2900 and 6000rpm for the rear (if you believe the maps have been set up correctly).

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08 Specialized Langster

This is a small cold start log showing some automatic idle advance adjustment. Looks quite strange to me: http://www.ecmspy.com/download/gunter/2 ... 103200.msl

After a day of modifying and testing these are my changes, which seem to result in a stable idle:
- copied the spark advance from the 2009 map posted above
- equalized fuel cells per row in the idle area

http://www.ecmspy.com/download/gunter/timing.jpg

Idle is still a bit erratic, but much, much better than before.

I also added another modification, that will give a bit smoother ride IMO:
- reduced deceleration correction value from 96% to 70%. Deceleration correction is active between 3000 rpm and 1350 rpm (= max idle rpm), with throttle closed. I can't really describe how riding differs, but it felt a bit better than before.
- reduced AFV increase/decrease factor from 105.3/95 to 102/98. Also reduced the numbers of transitions required from 21 to 10. Thus AFV changes faster, but with a smaller amount (2% instead of 5%). I ran a log, showing an app. 1800 ft. altitude change:

http://www.ecmspy.com/download/gunter/uphill.msl
http://www.ecmspy.com/download/gunter/downhill.msl

These logs are already converted to text format, therefore a bit larger than in binary format, but contain the full set of variables. Bike is stock 2003 XB9 except IB310 ECM and stock XB12 muffler with AMC activated.

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"It is often said that before you die your life passes before your eyes. It is in fact true. It's called living."
Terry Pratchett

Not looked at the attachments yet, but the 10 deg of advance made my idle smoother. I really wanted to get round to optimising the idle ignition timing at different engine temperatures, maybe next week...

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08 Specialized Langster

Hi Pash, how are you

I was wondering if you had any thoughts on this slight problem I have with my Uly. 06 bike, 11K, all new service parts, new battery, R/H scoop, Remus can and Powerizer, Ultimate air-box, etc. Fan and oil cooler working ok. TPS reset done, idle fine, timing done, etc.

What happens is that the engine runs very slightly rough which gives a very slight jerkyness on the road. Now most would say that this is normal but here is the rub.

The engine will, sooner or later, run perfect without the jerkyness. Like almost no vibs. I can read the 5mm high letters on my jacket (via the mirrors) at idle no problem, the front indicators are hardly moving and I can pull away from 20mph, in third, no probs without needing to slip the clutch. The engine becomes almost as smooth as my Aprilia RSV-R and the bike is a joy to ride.

The question is, given that the engine IS able run as good as this, why is it doing this and what is the problem. At the moment I turn the ignition on/off a few times and it sorts itself out after a while but tonight it needed a 20 mile run to do so.

It is most noted at steady throttle positions. Power on is fine but it does not feel like it goes as well as wene the engine has sorted itself out. It feels like it does it through the whole rev range.

It sort of feels like a plug that is missing or a slight imbalance of fueling to the cylinders. Not as I once thought down to ambient air temp, as it seems to do it anytime, or a cold engine as I pre-heated it before tonights run and it was still the same.

At the moment the only thing I can do is re-check plug gaps, timing and see how it goes without the Powerizer. It plainly goes from one state to the other but pining it down could be a problem so any advice would a great help.

Hmm, contentious issue, as you will find they all do it to a degree (except mine). SNB has a similar problem...

Assuming it is running in the closed loop area, I think it is cos the front cylinder is running lean, something Buell have done to give you more mpg. Not sure why turning the ignition on and off makes a difference, maybe the engine just cools sufficently to recover some margin against unstable running.

I have richened my front cylinder up so it runs at 14.7 in closed loop and 13.5ish in open loop. If I ride with another XB12R at steady throttle on the motorway, onanist for example, my bike will use 5% more fuel. But I prefer it like this as anyone who has ridden my bike will tell you it runs well.

I was interested in this thread cos it suggests that retarding the ignition timing will get rid of a similar effect. That got me thinking about whether the ignition timing at part throttle was right or not and if you could guess what it should be.

If it were an S1, you would just raise the needle a notch and you would be away... Cos it is fuel injection, you have to know where you are in the map and which cylinder is misbehaving to fix the issue.

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08 Specialized Langster

Hi Pash thanks for the info.

I have reset the plug gaps as they were to small and the electrode colour looked perfect. The TPS reset was last done 02/05/09 so I have done it again. The AFV was 98% (in the gauge box) so reset that and it now states 100% in the gauge box. Both done with the engine cold and the ambient was 28C. Fan comes on @ 220C.

Cold Start Enrichment went down to 100% @ 180C, 99% @ 200C and 98% @ 220C (bike standing). Is this ok and is 100% zero CSE. It was in closed loop but if you blip the throttle open loop flashes up sometimes. Is that normal.

Went for a run straight away (engine warm) and it was much better but not 100%. Stop, restarted the engine and it was 100%. The engine run perfect. I will try it from cold and see what happens

Update. Run it again after 4hrs standing and the same as before. Throttle control is great again. It will pull away in 5th from 40mph, 3rd from 25mph and hold 30 and 70mph with no juddering.

Sweet. Hope it lasts

Well , I did not know you needed to disable the O2 sensor , as soon as I did that the surging problem went away . The ecm spy manual says only to disable the O2 sensor if tuning on a dyno and then enable at after . It was running lean .
Thanks for the input from all .
Now that I have that fixed and have learned more about the Spy , I can do some more tuning . I love my XB9R even more now !

Just another thought about air cooling of the engine.

Last week I put the OEM plastic bit back on the r/h side to see what would happen and found that even at 80mph the fan was running. It seems to me that if the fan comes on at 220C @ 80mph then the thing is not getting enough cooling and my engine is well run in. With the r/h scoop on the fan only comes on in very heavy traffic or if I thrash the bike.

I sometimes wonder if the r/h scoop is cooling the rear cylinder to much because it is plainly pushing a lot of air over the back cylinder. Could it be, given the engine temp is taken from the rear cyl, over cooling is a problem.

I really wish people would not disable the O2 sensor...

So where does that leave you with your ignition timing sensitivity?

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08 Specialized Langster