Good afternoon my friends. I just installed the CV Performance Carburetor Tuners kit on my 06 XL1200. Changed out the idle and main jets to a 46/185, along with the EZ_Just idle mixture screw, and when trying to adjust the idle mixture per the instructions, as in turning the screw in untill the engine starts to stumble, mine never does start to stumble. Can someone shed some light on this for me please. Gonna go for a test ride now and see how it behaves otherwise. Thanks in advance for your replies.

 

Just got back, and it sure woke the bike up as far as running the crap out of it goes. Mid to WOT all I can say is wow! It seems to load up just a little coming off idle when I start out in first, and I think I can detect a little stumbling in the seat of my pants when I'm just cruising around the 45 mph area. Your thoughts fellas?

 

You need to lower the idle when you do the procedure. It should be below 800rpm for it to work. Even then, the engine may still run with the mixture screw all the way in or out, what you are looking for is the point where the engine runs the highest rpm. A little in or out and it will drop.

 

Back to the garage now. I'll post my results shortly. Thanks.

 

Sounds like it's running really rich. Was the original idle/low jet a 45? Usually one step up is what you'd do with a change to less restrictive exhausts. Have you changed the exhausts? But even if you have stock, it should adjust ok with one size larger jet; they're pretty lean from the factory; I'm running a size larger in both of mine with stock mufflers. That 185 jet should only make a difference at fairly high rpm, nothing to do with idle. That kit has a different needle, but I'm not familiar with it's installation; if for some reason it's too high, it'll mess up the idle mix that way, too. I'd check the plug color to see if they're indicating a rich mixture, and you could try putting a size smaller idle jet back in - that kit is supposed to come with a selection, or used to.

 

Seemed as though that helped somewhat. I'm gonna call it a day for now, and ride it some more later on. Thanks for the help. If I have any more trouble, I'll revive this thread. Thanks again.

 

It's basically a Stage 1, with SE mufflers, and a Hypercharger. It was running a 42/180, and a N4NN needle. It always smelled unbelievably rich, and it still does in my opinion.

 

One other question. That carb kit came with a drill bit to enlarge the hole in the slider. What does that accomplish?

 

I have the CV kit, and love it. So please take my experience as helpful, as I've used it on my own bike and many customer's bikes.

Do NOT drill the slide! It affects the rise/drop rate of the slide. The standard hole that H-D has is plenty. That's something you really don't want to mess with unless you understand the physics behind it and are really aiming to change that affect. I would say 99.9% of builds have no use to modify that.

My CVP kit recommend at 44/175 combo on the jets for my 883. The main was fine, but the pilot was wayyyy too rich. This is typical in many applications. I'll tell you what I would do.

Since you have a stage 1 1200 Sporty, start with a 45/180 combo and 2 turns out on the mixture screw. This covers 99% of builds. The main jet only comes in play if you are above 3/4 throttle. Most of your riding does not include this. I only hit that if I'm really going at it and consciously know I'm ripping hard.

The mixture screw is finicky. It's based upon orifice flow, which means that the adjustment to it is not linear (it's exponential). That means, that 1/4 turn out - 1 turn out may have a much larger effect than 2-3 turns out.

As I mentioned before, the 2-turns out is a pretty good starting point. From there, you want to ride it and adjust 1/4 turn increments based upon how it feels. If it seems weak and pops, turn it up a 1/4 and try again. If it feels great until you turn the throttle and then bogs down, turn it down 1/4 and re-try. It's a tedious process to get it truly dialed in, but when you do it's nice.

The needle in the kit is a good one. CVP has really done a great job on that. No need to shim it or mess with that in any way. Again, do not mess with the slide vacuum hole, because that will mess the needle up as it affects transition points.

I also don't really like the Hypercharger. It doesn't have near as much airflow as they advertise, or compared to other kits, but if that's your style it's not a big deal. It just means you may not need as much jetting as some lead you to believe.

A lot of guys overjet and never truly get things right. Hopefully this isn't too much information. Let me know if you have any other questions and I'll try to answer them.

 

Should I go back to the 42 idle jet perhaps? I really like that 185 main! That thing ain't ever been that much fun to ride?