Idles low despite screw @ max

[gnode]

History:
2005 kat. 1700 miles.
Stock
Carbs cleaned @ 350 miles in November (had been in storage since 2005 apparently). Ridden at least once a week since.

Live in Texas

Had the initial service done at ~600 miles. While it was there, I had the dealership remove the brass plugs in the carbs to get to the a/f screw and asked them to give it a 1/4 turn to richen it some. Always use premium gas in case I have to go out of town for work + bad weather may cause me to miss a week here and there on the bike.

Ride was great.. for a while.

Problem:
I have slowly had to increase the idle screw to raise the idle so it would stay running. Now with the screw at max, I only idle at ~900-1k RPM. It takes choke to get the bike started in the morning. Sometimes I have to keep the choke on for ~2-3 minutes while I am putting my gear on. Then I have to keep a tiny bit of choke on for about the first minute I ride before I can turn off the choke.

At this pace, I fear that in the next month it won't be able to idle.



Current plan:
I took off all the body panels tonight. Tomorrow plan to check the spark plugs to see if they are fouled, indicating that the dealership maybe overshot the richness (or that I requested them to overshoot..). Replace plugs if necessary, turn the a/f screws back some if necessary.

Does that sound reasonable? Anything else I should check while in there?

[TRH1]

I think you need to clean your pilot jets. The bike has not got enough fuel flow to idle properly.

[GregS]

Quit using premium fuel. It can foul plugs and build carbon deposits.
It is normal to need fuel enrichment when starting cold. Your usage sounds a little much but not necessarily bad.
You could try a dose of Sea Foam or your favorite fuel system cleaner. Use something made for carburetors. Fuel injector cleaner works better under high pressure and can actually cause carburetors to clog, rare but true.

[steves]

IF you have the idle screw turned all the way up, and it won't idle right than the carbs are dirty beyond what fuel additives can address. you'll likely need to clean, and dis-assemble them to get all the gunk out.

The other possibility is that you've messed with the idle screw and somehow backed it out so that it's no longer adjusting anything. You'll at least need to pull the air box to check.

Ultimately, you should not be making any major changes to the idle adjust screw and you shouldn't need to.

[gnode]

I have put about.. 1 or 1.5 cans of seafoam through during the past 1000 miles. Does not seem to have affected much.

Are you serious about using regular instead of premium, and premium causing deposits? I have not heard of that.

IF you have the idle screw turned all the way up, and it won't idle right than the carbs are dirty beyond what fuel additives can address. you'll likely need to clean, and dis-assemble them to get all the gunk out.

The other possibility is that you've messed with the idle screw and somehow backed it out so that it's no longer adjusting anything. You'll at least need to pull the air box to check.

Ultimately, you should not be making any major changes to the idle adjust screw and you shouldn't need to.

Would it really be possible to get that gummed up since having the carbs cleaned late November? I have been driving it at least a couple times a week since then, through november. That just seems surprising to me.

I do know that the idle screw does seem to feel different. It feels "dead". I have to turn it pretty hard to get it to move. What should I look for in particular? I plan to pull the fuel tank tonight.

I heard the idle screw is supposed to be spring loaded for easy turning, but mine does not feel like it.

[steves]

If it's bound up or not moving, the sheath could be rusted or disconnected.

You should be able to tell if it's still attached or not.

Might be worthwhile to pull the carbs off and do a bench synch.

what was the "full cleaning" last fall? How full was it? Did you use a stabilizer in the gas over the winter?

[05RedKat600]

Are you serious about using regular instead of premium, and premium causing deposits? I have not heard of that.

Doesn't cause deposits per se, but it does foul your plugs. These bikes come from the factory jetted and tuned to run regular. Running premium causes an essentially rich condition, and really is not needed. You can rejet/tune for premium, but they run just fine on regular. Unless you've done the timing advance mod, then that may require premium as well.

Sounds like the cable for your idle adjustment is bound up in the sheath, and may be actually broken. This would cause you to adjust it with no real gain, and may allow vibrations to back off the idle adjustment at the carbs. Sounds to me like you need to investigate this cable.

[gnode]

Thanks for the tips. Will do this tonight when I get home.

[gnode]

If it's bound up or not moving, the sheath could be rusted or disconnected.

You should be able to tell if it's still attached or not.

Might be worthwhile to pull the carbs off and do a bench synch.

what was the "full cleaning" last fall? How full was it? Did you use a stabilizer in the gas over the winter?

I took it to a shop and they pulled the carbs and cleaned them. They fully disassembled them (I saw them on a bench when I stopped by to check in). They were gummed up from fuel sitting in them for 5 years, but otherwise brand new (300 miles). They cleaned it out, put them in, and it drove perfect.

It was never in storage "over the winter". I live in Texas and rode it almost every day. Commute is about 16 miles round trip and I have logged 1400 miles since November/carb clean.

I have always used premium and there has been a steady decline.

Going to double check the idle screw now, and the spark plugs. Will check back in a bit.

[05RedKat600]

Texas? What's the ethanol content down there in the fuel? Worth a shot to add some Sta-Bil to your gas if you don't ride it consistently. Might be a case of evaporation plugging your jets, especially in the heat down there and not being ridden every day.

I was just down there last week at the Federal Reserve bank. 100 degrees, and humid as hell! Don't know how you guys stand it.

[gnode]

It is usually 10% but sometimes I see 15% out there.

Here are my plugs. Poor light. Let me know if you can make anything of them. I always have a hard time reading plugs unless they are just outright trashed.

My wife is taking a pic with her real camera and will email it to me soon of a close up of the worst plug.





Close up of the worst one (#4)





I drained the air drain hose and it had a fair amount of gas. It may have actually been completely full. Hard to gauge volume in a hose like that.

[steves]

They look a little rich.

Never trust a shop. What they 'say' and what they 'do' are often completely different.

I will 100% guarantee that if your bike isn't idling right that either the pilot jets are still clogged or there's trash in the carbs/tank.

[gnode]

Took the air filter out and saw this. Wondering if it matters or indicates something.

Air filter with some gas at the "bottom" of it (if it were in the bike)


The carbs, some gas coming back the wrong way?


Evidence of a pool of gas at the bottom of the airbox. This must be what I drained:



Should I wipe this airbox clean??

[LMT]

Idles low despite screw at max.

Somewhat similar problem that I asked about recently. My idle screw is so tight I cannot turn it in to increase idle (900 rpms). Feels like the spring behind it is ready to snap. Not sure why. Haven't had to adjust it in 3 yrs. Always idled nicely at about 1100-1300 rpms. Might be the fuel left in since Dec. (live in Ohio) even with StaBil and Techron added.

[05RedKat600]

Somewhat similar problem that I asked about recently. My idle screw is so tight I cannot turn it in to increase idle (900 rpms). Feels like the spring behind it is ready to snap. Not sure why. Haven't had to adjust it in 3 yrs. Always idled nicely at about 1100-1300 rpms. Might be the fuel left in since Dec. (live in Ohio) even with StaBil and Techron added.

Fuel left in since Dec? You gots a case of plugged jets too then, most likely. Quick check? Drain old crappy gas, insert fresh new gas. If it still runs bad, clean the carbs.