C12 to U2

[MarkSims]

The shop where I've been getting my C12 for the last couple of years said they're not carrying it anymore. They've replaced it with Ultimate 2.

So what I'm trying to decide now is: Do I start looking for C12 - or do I switch to U2?

How much more power should I expect from U2? And is the power across the board - or only top? I ride an Eric Gorr KX310 and my son rides a stock KX85.

If you recommend the U2, how would you suggest I modify my jetting as a starting point? My bike is currently jetted very crisp - definitely not rich anywhere. My son's bike is close - but is a step rich in the needle or main.

I searched for ultimate and didn't find anything useful. The post I did find addressing switching from C12 to U2 on a CR250 had a reply stating that no jetting change was needed in his case. That doesn't seem right to me since the U2 is oxygenated.

Thanks! Mark

 

[elf]

I just switched from c12 to u2 on my 144. It does run a little leaner than c12. I have been playing around with u4 and mixing it with mr2 also. The bottom line is it runs leaner with the oxy stuff. The power is across the board, it doesent really feel faster, but then when your riding you will find your mixed up as to what gear you are in. You think your in 2nd but your really in third. or think your in 3rd when your in fourth.