EFI & Yosh RS4

For those of you with the Yoshimura RS4 exhaust, what EFI mappings are you running? Initially I was running the Jay Marmont mapping but the pipe started to discolor (it's not Ti) so I went back to stock (all zeros). I've played around but haven't found anything I'm really happy with. So... what are you running?

Been using this map for almost the entire time since having the pipe, really pulls harder. Can especially notice the difference when hill climbing.

"Setting for improved response"

"This setting is suited for a linear engine response to throttle work when riding on dirt with good traction or on high-load sand courses. This setting helps to achieve faster engine revving up through the rpm range for owners who want to ride more aggressively."

Fuel Injection (FI)

-2 -4 -4

-2 -4 -4

-2 -2 -2

Ignition (IG)

+3 +2 +2

+3 +3 +2

+3 +3 +3

The first 5 inches or so of my YOSH stainless head pipe changed to purple and the remainder of the head pipe is a very light goldish color, is it not supposed to change color after you ride it? I thought that this was normal even for a stainless pipe. The bike runs perfect..

Of course it will change color. The pipe can heat to over 900 degrees. Stainless will turn dull and brownish with time. Ti will dull near the head, but stay a blue or yellow color for much longer.

For those of you with the Yoshimura RS4 exhaust, what EFI mappings are you running? Initially I was running the Jay Marmont mapping but the pipe started to discolor (it's not Ti) so I went back to stock (all zeros). I've played around but haven't found anything I'm really happy with. So... what are you running?

Less hit or broad map is what I have been using depending on track conditions. The Marmont map is the next one I'll try.

Of course it will change color. The pipe can heat to over 900 degrees. Stainless will turn dull and brownish with time. Ti will dull near the head, but stay a blue or yellow color for much longer.

Thanks Grey, Jeepnjt it sounds like you should just run the Jay Marmot map that you like and not worry about the pipe color, its all natural and normal. :excuseme:

Thanks Grey, Jeepnjt it sounds like you should just run the Jay Marmot map that you like and not worry about the pipe color, its all natural and normal. :excuseme:

I'm not so sure. I have the stainless RS4 and the first twelve inches of the pipe turned bluish - similar to what a Ti pipe looks like when it's hot. It's my understanding this occurs because of a lean condition (when this happens to a stainless pipe).

I'm not so sure. I have the stainless RS4 and the first twelve inches of the pipe turned bluish - similar to what a Ti pipe looks like when it's hot. It's my understanding this occurs because of a lean condition (when this happens to a stainless pipe).

I think this is a myth, my pipe turns blue then brown after its cleaned and polished and my bike is definently not running lean

I'm not so sure. I have the stainless RS4 and the first twelve inches of the pipe turned bluish - similar to what a Ti pipe looks like when it's hot. It's my understanding this occurs because of a lean condition (when this happens to a stainless pipe).
It happens because the exhaust gets hot, stainless or otherwise. The SS pipes on both my '06's are dark all the way to the midpipe.

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