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Just finished a few mod's on the bike. She runs MUCH better than before, but I now have a couple of odd issues:
(1) Would not start with choke on at 38*. I cut the choke off and it fired right up with a tiny amount of throttle. Normally I would ALWAYS have to use the choke at this temp, so I'm guessing I'm too rich.
(2) When set at an acceptable rpm, the idle is not stable and surges up and down, eventually stalling. If I cut the idle up enough that it doesn't die, I'm idling somewhere around 2000+ rpm's (don't have a tach, but idle is obviously way too high). If I move the idle screw (even a HAIR) to lower it, idle drops way down and starts surging again.

Here's what I've done:
-----valves shimmed back to spec' (didn't need much)
-----pink wire switch (presently still in X mode until I get the jetting correct)
-----top of airbox cut to 4" x 4"
-----No Toil filter kit installed (backfire screen removed)
-----exhaust is stock w/ baffle removed
-----Boysen QS3 installed....per instructions, leak jet screw set at 3/4 turns out for #42 pilot jet
-----installed crfsonly fuel screw
-----JD jet kit installed....per instructions for my temp and altitude, blue needle with clip in middle (4th) position / #160 main jet (compensating for airbox mod' and colder temp) / #42 pilot jet / fuel screw at 1 3/4 out / thin o-ring mod'

Temp at the time of testing was 38*F and altitude was around 800 feet.

Assuming I'm running rich (based on the choke issue), what should I change to correct it?

Is the surging idle issue related to being too rich or a separate problem?

It runs MUCH better than before. More responsive, more power, annoying off idle bog is gone and I'm pretty happy with the results thus far. But I can't live with the idle problem and being so rich that the choke isn't needed for a cold start concerns me.

Any thoughts?

Turns out I had the fuel screw at 2 1/4 turns out. I guess in the process of adding the jet kit (which spec's 1 3/4 out) and adding the QS3 (which said to richen it 1/2 turn out), I must have done both and it didn't like that. So I changed it back to 1 3/4 and that helped the idle issue, although it still isn't "smooth".

That's as far as I made it before having to deal with an oil leak . http://crfsonly.com/forum/viewtopic.php?t=40487

I'll try going in another 1/4 turn after I get the leak fixed.

I had a fit trying to get the '06 to run cleanly off idle.

Both a 42 and 45 pilot could be used to get an A/F ratio of around 12.8-1.
But, it would bog like crazy trying to give it any throttle after that.

I finally found that the stock needle was crazy lean, and even a big fat accel pump squirt couldn't mask the lean spot that occurred when the throttle was opened.

Thank you, California green sticker people, for forcing mother Honda to deliver a bike that doesn't run, so it could be used on public land.

I ended up 2 clip positions richer on the needle just to get the A/F around 13.5-1.
Maybe James' needle has a thinner taper (richer).It almost certainly does.

So, a lean needle was masking what seemed like a lean pilot circuit.

A 155 main jet is plenty rich enough. At higher altitude, 6,000 feet, I use a 148.

a 45 pilot is probably the trick also.

Your bike is never going to start as well at 38 degrees as it does at 80. Fuel doesn't atomize as well at colder temps, the oil is thick as pudding, etc.

I tried another 1/4 turn in (1 1/2 out) on the fuel screw and it didn't seem to help, so I changed it back to 1 3/4 out (JD's recommended setting).

Another guy mentioned checking the hot start valve to make sure it is closing completely, so I'm gonna check that tonight.

You think going down (richer) 1 clip on the needle will help?

From what I've seen about the leak jet function, I can't imagine it's setting would have anything to do with the idle. I haven't adjusted it yet.....trying to just change one thing at a time.

I've always been a 2 stoke guy and this is my first "modern" 4 stroke. The FCR carb is blowing my mind.....but I'm learning.

If you still get a bog when you twist the throttle from idle, then yes, go another clip richer on the needle. It can't hurt to try.

The leak jet is probably overly hyped. I pinch mine shut to deliver maximum squirt. Only on the X's, not the R's. It works great, and I am at high altitude where you would think that the bike would be over-fueled.

No bog at all now. The JD kit cured that completely and it's much more responsive and with more power.

The only remaining issue is the idle....and the fact that it doesn't want to start with the choke on, but starts easily with a touch of the throttle and the choke off. That makes me think something is TOO rich, but I haven't checked the plug yet. I was hoping to get the idle issue straightened out before checking the plug.

The hot start isn't the problem. My buddy said the idle should increase because of the increased air, but he was wrong. RPMs drop when the lever is pulled....and will die if at idle.

It was starting to snow so I didn't have time to adjust the needle.....but the needle doesn't come into play until you start rolling into the throttle, right?

Doesn't the pilot (along with the idle screw) control all idle function? If so, do you think I need to step up to a #45 from the #42 that's in there? A #40 was stock, but it presently has the #42 that came in the JD kit.

I thought I'd post my findings. With Ken's help, I figured out that I had installed the floating valve plate on the slide upside down.

What a bonehead mistake......but in my defense, I've gotta say that it looks like it should go the way I put it in. The top of the slide is flat and the bottom has a "V", so I oriented the plate in the same manner. WRONG!

It now starts properly and idles fine.

Thanks for your help Ken!

You're welcome! Glad to hear that was the issue!

Ken