Weird shit we don't understand???

Mark has been building a few more GRiSO maps and I've been testing them in tandem. We've both observed various strange behaviours and inconsistencies.

F'rinstance to try and eliminate the popping on the over-run he chopped the fuel completely at 4.7 from redline down to 2.5 grand. Very effective at killing the popping obviously and you could feel when the fuel comes back on but it made the entire rest of the fuelling feel stupidly lean! Lots of vibes, much more noise and a lot less action at pretty much all engine speeds and throttle openings.

So a few tweaks were made to the DE63 map and one was supplied to me with zero fuel on the over-run, (Closed throttle, 4.7 TPS.) and one with 1MS of fuel delivery at that point.

I spent a couple of hours this AM testing them all. Yesterday i'd gone for a flog with the first 'Zero Fuel' map I'd recieved. This is the one I think Raf and Gary are running and while it was OK it was vibratory and lean feeling. Swapping back to the DE63 map showed a great improvement this morning but like some of the very early iterations of the 'Beetlemap' used with the Termi with dB killer there was a noticeable flat spot in the midrange and at the top end at full throttle. This may of been temperature related but by the time I got to Queanbeyan the bike was good and warm and ambient temp was in the mid teens centigrade.

I swapped maps in the car-park of the Queanbeyan KFC watched by bemused, burning fatties eating lard and stuck in the 1MS fuel map and rode back to Bungendore via the Captains Flat road. Huge improvement. Smooth, linear, no flat spots detectable apart from a tiny weakness at 3,250-4,250 rpm which I might just be imagining, I called Mark, he too had noticed this and was adding a weeny bit more fuel in that range.

Back in Bungendore I stopped and uploaded the second 'Zero Fuel' map. While the results were a lot less extreme than the previous iteration with zero fuel there was still a big diminution in overall performance and an unacceptable increase in noise and vibration. While doing this upload I was also hassled by the highway patrol. Apparently staring at a laptop screen at the side of the road makes you the sort of suspicious ne'er do well that attracts the attention of the wallopers! I suppose I'm lucky I wasn't arrested on terrorist charges given the obviously dangerous nature of my activity! Pricks!

A brief ride was all that was needed. I stopped and swapped back to the 1MS map and all was sweet again. Gary and Adrian's brother Ralf, next time you're up here we'll have an upgraded map ready for you.

What I can't understand is how and why the removal of all fuel from those few cells can have such a profound effect on the entirety of the rest of the map when NO other changes are made??? Mark's baffled too.

Pete

That is curious...

I am going to go back to a previous version as the current map I am running isn't quite as "smooth" as the prior map I was running. But that may also have a lot to do with the warmer temperatures and higher altitudes I have been riding around here east of Sacramento towards the Tahoe area.

It's worth some experimentation at least.

I went hooning with the 1mS map (which will be officially known as the C735 map) and I'm somewhat loving it.

As far as performance is concerned I think its pretty much nailed now. The trick is going to be tiny adjustments for different pipes and the like to maintain the smoothness and linear nature of the delivery. The C735 map is very nice with the Mistral and while inoffensive when pobbling around town or cruising at highway speed it has a very pleasant, deep, note when you stick the hammer down. Lean running produces a much harsher note, rich running makes it sound chuffy.

Pete

Mark did you take the fuel out only on lowest two tps columns or more? I tried with 4.6 to 5.8 (4 columns). And yes it stops popping but gives a less fluent ride.

Still puzzles me why we have that at all. it seems to be a lot more with a short open silencer. Not all carc bikes have it. But a 1200 sport stock , does it a lot.

pauldaytona wrote:

Mark did you take the fuel out only on lowest two tps columns or more? I tried with  4.6 to 5.8 (4 columns). And yes it stops popping but gives a less fluent ride.

Still puzzles me why we have that at all. it seems to be a lot more with a short open silencer. Not all carc bikes have it. But a 1200 sport stock , does it a lot.

Paul, I did a few different versions, one with 4 columns lke yours, and one with 17 columns with a curve applied from from 4.6 to 41.0.

The popping occurs on a closed throttle on the overrun because the injector pulse-width is non-zero on a stock map, and even though revs drop quickly, it does take finite time. Some fuel is injected that transitions the combustion chamber to ignite inside the pipe/silencer, thus causing the pop.


I'll send you the test maps and you can have a look yourself.

Testing on that map tomorrow Mark...

Tony. No worries. I'm sending you a Sport map with the same treatment.

Greedy grin here...

I am not a fan of the zero map, I ran the 17 0 coloumn with the curve yesterday and it may work for the high plains flat landers...but the maps that cut fuel are very harsh in response in the tight mtn roads. I had had to stop and re-map at the side of the road as well. the big issue with these zero maps is the abrupt fuel on and off during the middle of long fast turns downhill. Very often I have maybe a mile or two of down hill with a 2000ft elevation change(or more) and you wind up with this map hitting to zero fuel spot cutoff at maint. throttle on the longer sweepers even though you are doing 70-80mph, it is only with the throttle cracked at the end of the long run, just very low load.

I noticed on the 4 coloum zero map my bike was acting lean....vibes were soso not horrible, and actually it must have been lean to a degree as the plug temps had gone up some.

Would you send me a copy of the the c735 , I havee one I will send you that I modded from your four col zero map That I like (but I am running stock exhaust)

Another thing that I suppose might be effecting the results might be the hot/cold upload issue although most recent maps I've tried haven't noticeably been troubled by that....

Pete

Well I love the new Beetle iteration. Loaded it this morning and WOW!

Should I sing mark's praises? Why Not:

Oh Beetle, thou art wondrous,
The Guzzi, she is thunderous,
She pulls like a train,
Right through the rev range,
On/Off throttle is not such a lurch,
How I love my Guzzi perch

Seriously, this is a good map Mark. I had to learn the feel of the throttle but once there thoroughly enjoyed the ride to work today.

Economy: I think we have a global problem with oil/fuel production; if we keep going down this road we will send the oil companies broke. I would be happy with mid 5s/100l. However today, when I would have averaged 5.6 or 5.7l/100km, I saw it dip to 4.9 twice - however I fixed that by pulling up to traffic lights where it went back to a sane 5.0l/100km. What gives here? Great map, great economy. Temperatures never got over 13 degrees C and 11 was the normal temperature

This gives a fuel range of better than 380km before reserve comes on. Effen awesome! Used to be happy if I got to 320km...

Still have the 200rpm difference. Into neutral for 2-3 seconds and all is right in the idle department again. Weird shit indeed - but I can live with it.

Thanks Mark.

Aww, shucks Tony.   

Just to be on the safe side and me pics of your plugs after you've ridden for a while. As far as that 200 rpm thing is concerned, I can explain it for the GRiSO 8V, but not for a 4V Sport.  I'll have to add that to the 'weird shit' list.

Will do Mark              

Took the c735 for commuting this morning. The map feels good. But I have the mtxl now, so could see that over 4200 rpm, it's to lean. lambda going to 1.06 Also when accelerating in that range, lambda stays high. Closing the gas, did lean it out as supposed with the 1000 cells.

I don't think so. If you are relying on lambda readings alone you aren't taking into account the charge transition issue. Run it at the 'Problem' area for a bit and chop the plugs.

Pete