I ride in the mountains around Denver, CO at around 7 - 9,000 feet. The dealer I bought it from changed the main jet from stock 158 to 152.5. It actually seemed to run worse.... I talked to another dealer in town & he told me the Rubicon is the one model they don't rejet. I installed the original jet in it & that helped alot. Anybody have any experience with this, or any ideas. Also has anybody installed a K & N jet kit? & did it make as much difference as they claim? Thank for your help.

 

I don't ride a Rubicon, so can't say much about the jetting, but I do live in Colorado Springs, and for where I ride (local and higher elev.), it helped a fair amount. My Rancher originally had the plugs pretty dark; not fouled, but definitely rich. I had tried the a smaller OEM jet as well, ran well, but not the mid-range as with the dynojet and K&N combo (this is what is included in the K&N Kit).

Also, some may say it is cheaper to just buy jets, but jetting at altitude is a trial and effort exercise. The kits come with several main jets, so I feel it is easier to have them available in case it takes you 3-4 evolutions. The Kits get you pretty close with the instructions, but you may need to do some testing.

 

Fey Meyers told me not to rejet the ruby,but after riding at 8000' I decided to rejet it and the thing runs alot better, no lag time and it now does a little better on fuel. Can't wait to ride in the high country the winters are way to long sometimes. Happy Trails!!!!

 

The Rubicon runs rich at 0-3000 with a 158 main. Get the jet kit and a filter when it comes out. If your dealer does not rejet Rubicons then they should not be rejetting anything with a carb. There is no difference in rejetting a Rubicon.

 

Hey mtnman, what did you rejet it to?

 

Hey tex, I am at 2,000 feet and my rubicons plug is a dark brown, It also doesnt like to fire up when warm, should I drop the needle, smaller Pliot jet or both? Mine seems to run clean wide open and I also do alot of sea level full throttle dunes would it hurt to drop the main to a 156?