Rejet after adding discs??

[Glamis400ex]

I have a full Rossier exhaust on my crf hybrid. It's super loud so I bought some Supertrapp discs and end cap and installed it on the end...hoping to quiet it down a little. I have 8 discs on there now.

Do you think I'll need to rejet my main?

[deathman53]

by adding discs you made it louder and less backpressure, thus leaner jetting. Deleting discs will make more backpressure and richer and quieter. I have 2 supertrapp exhausts, I'd think it would work very similar. You had a open end cap(kinda like TC shorties). If you did and installed the supertrapp discs and solid end cap. You richened it, increased back pressure, added a spark arrester and added low end power. The more discs the more top end power, less backpressure and leaner jetting. On my crf hybrid, I have a TC shorty, very loud. I removed the TC end cap and put in 12 discs and supertrapp end cap, it reads 96.3 dec.

[Glamis400ex]

yup, my exhaust is straight thru to the end cap. My jetting is spot on with the Rossier. So, adding 8 discs will richen it up a bit...I understand that. I'd rather be a tad rich than lean. BUT.....even if I throw 12 or more discs on, I've still added some restriction and back pressure and I believe it would still be rich.

If my jetting is spot on, with the straight thru Rossier, I don't believe I can get and leaner by adding discs.