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Discussion Starter #1
Had a fun trackday earlier this week - my fourth with my lovely 1090RR (and for the fourth time I was the only MV on the track that day, which I find a bit sad).
Here's a short video of my last C group session - got bumped to B after an instructor figured I was fast and smooth enough to move up with the next group: https://www.youtube.com/watch?v=c1X-34hssAA

Right after my last session of the day with the B group, two guys who were following me told me that my exhaust was on fire a good 10 seconds and they thought this was an awesome sight. I didn't notice it as it extinguished itself apparently.

See picture attached, the CF tip is clearly on the crispy side. The day wasn't particularly hot, the bike was running well, with standard gas and the only thing different from previous track days is that I now have a Microtec installed with a custom map from Marc Salvisberg.

Any pointer as to what might have caused this? All theories welcome ;)
 

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Heat.

For starters, do you have a dyno print out showing the wideband readings relative to stoichiometric?

Motorcycles spend a great deal of time at less than 100% throttle opening, and if you are a C-group rider, it's quite possible that you're spending less time at open throttle than B-ground, A-group, and licensed racers. If you're running lean at less than 100% throttle, it's not going to show on your dyno print out, but it will definitely do damage.

It would probably be impractical for you to obtain EGT info in real time, but I suspect that this is where your problem is.
 

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Discussion Starter #4 (Edited)
Here's a scan what Marc Salvisberg at Factory Pro gave me. He told me it's the highest gain in torque and horsepower he had ever seen after installing a Microtec ECU (my objective was to make the bike run smoother than it already did and it does now).

I also noticed that the bike runs a bit hotter than before. My dash temp gauge doesn't go down as much as it used to when riding at freeway speed on cold Norcal mornings (cold is 55 degrees where I live). It feels and sounds completely different than before the ECU upgrade that's for sure.

Saw the note about the arms. Gotta a lot of work to do on my form and stiffness ;)
 

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Here's a scan what Marc Salvisberg at Factory Pro gave me. He told me it's the highest gain in torque and horsepower he had ever seen after installing a Microtec ECU (my objective was to make the bike run smoother than it already did and it does now).

I also noticed that the bike runs a bit hotter than before. My dash temp gauge doesn't go down as much as it used to when riding at freeway speed on cold Norcal mornings (cold is 55 degrees where I live). It feels and sounds completely different than before the ECU upgrade that's for sure.

Saw the note about the arms. Gotta a lot of work to do on my form and stiffness ;)
Not trying to be critical of your form- just concerned about your safety. With proper form, speed will come as a result.

Regarding your dyno image, the resolution is not fine enough to be able to help, although is appears that your final air/fuel ratio is richer than your starting air/fuel ratio.

The only meaningful thing I'm gleaning from your print out, is that it appears that the bike was dyno'd with the db killer in place, but I'm not seeing any db killer in place in your photo.

And even then, we're only talking about what happens at 100% throttle. I have a feeling that your issue is happening at less than 100% throttle. Mapping is a 3-dimensional thing.
 

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I think what you'll find, based on my experience with the same exhaust on my 2010 1090RR that has also been mapped, is that the bike will pop on sharp decel due to excess fuel and that will cause the Crispy Critter exhaust. It is probably exacerbated by track riding.
 

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Discussion Starter #8
Yeah I did get a pop or two when closing the throttle from high revs. I used to get a lot more popping and at lower revs with the stock ECU and this exhaust when riding on the street. My main concern is making sure I am not damaging the engine the two or three times a year I ride on a track. Now I need to find a replacement tip for my exhaust or maybe I'll keep it that way as a battle scar ;)
 

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EGTs go up when you're lean, not when you're rich.

Melted pistons, spark plug electrodes, and so on, are from lean mixtures, not rich mixtures.

And if it's even leaner than that, if it's so lean that it's unable to ignite under compression, it probably will ignite after the exhaust valve opens and releases it into contact with the hot exhaust gasses from the other cylinders. Shooting ducks (the popping) is most likely because the mixture was too lean to ignite, not because it was too rich.

Your original trace may be richer than stock at 100% throttle, but like I said, I suspect that your problem is happening at something less than 100% throttle. Remember, mapping is a three-dimensional thing.

If you install an aftermarket exhaust system, have had only the 100% throttle mapping adjusted, and then remove the db killers, I would expect it to torch the tailpipe from being too lean at something less than 100% throttle (where you spend most of your time).

I'm not seeing any black soot on that tailpipe.
 

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Interesting, I'll ask my dyno guy.
 
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