Fuel/Ignition mapping

Firstly, I’m not going to cover work done by others – cleverer than I. Suffice to say, the best chap I know for Capo mapping info in detail is:- ‘Catfish’. Secondly, the only modification from standard on the RR, is the use of Iridium spark plugs. The air box snorkel is NOT removed, nor do I have a K&N air filter in place. Frankly I think both mods are a waste of time and money – this ain’t no race-rep!! Thirdly, I’m not going to endorse ‘Tuneboy’, the ECU software & cable kit …. but without it (as of September 2010) your only hope of remapping the ECU lies in the hands of the ever-expensive dealers – your choice!

What I’m going to do is try to detail my experiences with the RR and how it eventually arrived at the ride quality the manufacturer should have achieved in the first place.

In the beginning…..
From day 1 the RR ran fine over approx. 4K rpm and rather suspect below ….. as it warmed up it would occasionally stutter, cough, misfire, call it what you like. It would then run fine for another 3-5 minutes or so, then do it again. It seemed to do the same thing on the move, always with a light throttle, below 3K rpm … slow steady traffic sort of stuff. I checked all the electrics and fuel system, fitted Iridium plugs (no difference) – nothing made a difference. Some days it seemed worse than others, but ultimately it was only annoying – a trait of a fine Italian steed some might say!

Time for action
Eventually a Tuneboy kit came along. The first thing I found was that the installed map was old (2003) – version 050115 and the last version listed is (2005) – version 050429. Bear in mind these maps are for a bike fitted with an 0² sensor and catalytic converters in the exhausts. So I simply updated the map … nothing else other than checking the Tuneboy diagnostics feature to make sure that everything else looked normal.

I then covered a few hundred miles or so with no drama … in fact the one thing that was noticeable was the lack of idle ‘cough’ and a smoother ride at 2-3K rpm on light throttle. Overall, a nice improvement but not quite right. I asked myself ‘Ok, so what differences are in the map to make the improvement?’

Into the maps……
Finding the differences between 115 and 429 turned out to be quite simple – only the fuel/air map was involved. here they are for comparison:-

The difference was simply sections of the map changed from 14.5:1 down to 14.2:1 …… BUT this has big implications! As ‘Catfish’ tells you, when the map is set to 14.5:1, the system tries to operate in ‘closed loop’ mode, using the oxygen sensor feedback to try to maintain the air/fuel ratio rather than using calculations to try to determine the mix. Two VERY different ways of doing the same job!

The problem is that the 0² sensor ‘hunts’ rhythmically – rich to lean to rich – and so on. It was my guess that the motor just didn’t like being run this lean and occasionally stumbled while running. By changing the 14.5:1 to ANY other number, the closed loop is deactivated and I presumed that was why the bike was happier idling on ‘calculated’ mixture. So, step 2 ….. I changed ALL the 14.5’s to 14.2 thereby removing ‘closed loop’ function completely.

….. deeper still!
Catfish has done hours of dyno time with his Capo and very generously shared the info and files with us all. One option I had was simply to update the RR with one of his maps. I was concerned though that this would make LOTS of changes all at once and without a dyno, I just wouldn’t be able to sort out any running issues. What I opted for in the end was to simply add his modified Futura ignition map into my ‘modified’ 429 map. In it went and again a few hundred miles went under the belt. Once again I could only conclude it was a positive upgrade – so it stayed.

After the dust settles
As I piled on the mileage I noticed that the idle would sit a bit high, 1,450 – 1,500 rpm when the motor was good and hot, compared with the stable 1,350 rpm as it came off the electronic choke from cold. First off, I cleaned out the ‘Idle Stepper Motor’ – a slight improvement. Then I reset the ‘Idle Stepper’ function on the Tuneboy dash from 4 to 0, effectively making the ECU re-learn where idle is. This has cleared the problem, and to date the Capo runs smooth and ‘cough’ free and returns approx. 45mpg. Not bad with 16 tooth gearing, TKC-80 tyres and luggage like barn doors!

This is the map I currently use in the RR:- 050429_modified_KB.dat
1. Modified Futura Ignition map
2. Closed loop removed
3. Fan switching changed from 106/102/106 to 97/93/97