Triumphrat

AndyS4 · 05-12-2009, 01:23 PM

Hi. Iv got a leovince exshaust on my Speed four. With the standard pipe it doesn't lurch
(it may not be noticable) but with the Leo vince the bike lurches between 2-3,000rpm while trying to keep the speed constant. Iv tried to fix this problem on the tuneboy software by increasing the fuel between 2-3,000rpm but this has little affect. Does anyone know of a fix as i know this is a problem on the tt600 and S4.

Cheer's.
Andy.

Will · 05-12-2009, 02:30 PM

Two things will help.

First, if you have TuneEdit, take a look at the timing map. You will see a big hole between about 2000 and 4500 rpm. Fill it in and flatten it out. It's there for emissions reasons as far as I know and it's part of the bike's weirdness in the specific rev range. It's not just a TT600/ S4 problem, for what it's worth. Lots of injected bikes have similar issues, but we have TuneEdit. They don't.

Second, up the fuel idle trim with TuneEdit or TuneBoy. When you put the open can on the bike, it runs leaner. Leaner can be herky jerky, and it's really bad if you lean out the map. I know this from having made my bike idle really poorly and run really bad up to about 5000 rpm. Increasing the fuel idle trim a bit at a time and seeing what happens will likely solve the problem even if you don't mess with the timing map.

AndyS4 · 05-12-2009, 07:00 PM

Maybe ill put a little more fuel in then. Iv got the idle trim set to about 28 i think. stardard on mine was 20.3 ill have a look at the timimg too.

Just had a look at the Tune Edit

I have

Fuel Map. Ignition. Ignition Limit. Idle Ignition. fuel % trim. Ignition Trim. A/F1. A/F2. Idle. warmup.

Im not sure which one to smooth out. I suspect it's the Ignition map as this is flat till 3500 the goes way high.
Could you confirm this for me Will.

Will · 05-13-2009, 04:21 PM

Yes, it's the ignition map. Look at the matrix at small throttle openings and right around 3500 rpm. You will see the numbers drop and then go back up. Edit the numbers to be even with what's around them.

Since you put an open can on your bike, it's running lean, and it will need more fuel to keep the ratio where it should be.

AndyS4 · 05-14-2009, 09:54 AM

Sorry Will im not too clued up on the way the ignition map work's. The figure in the boxes. What does it change. Also what does the Ignition limit do?

Will · 05-14-2009, 08:21 PM

Don't worry about the ignition limit. I don't know what it does. I probably should, but it's a mystery.

Take a look at the matrix representing the ignition map. You will see a column of numbers in a green area on the left. It's the throttle opening. The numbers in the green area across the top are RPM.

If you look at the middle of the matrix, at approximately 42% throttle openings, you will notice the ignition map numbers rise steadily from 900 rpm to 12500. You will also notice the numbers below the row take a funny downward lurch at 2800 rpm and then are back to where they would be at 3500 rpm. I'm looking at map 10115, a map for 2002 and later TT600s, but stock maps will all be similar.

What I always do is increase the value in each of the parts of the matrix in the area where they take their downward lurch. There is nothing good about having the timing retard in this part of the rev range unless you are trying to get past an emissions test. The bike won't be running in the tested rev range 90% of the time, and the retarded timing will just screw up ridability the other 10% of the time when you are in traffic or starting from a dead stop.

I hope this helps.

AndyS4 · 05-15-2009, 09:16 AM

MMM. my ignition map doesn't look like that. My limit map look's like your saying though lol. Maybe we have a different program. My ignition map has calculated load instead of throttle position too.

The ignition map on mine has 20 in all the boxes between 0 load/900rpm and 101 load/3500rpm. at 4500rpm the values double to around 40 and steadinly increase to around 60 at 12500.

maybe ill smooth the ignition limit out.

Andy