Carb %#&@*&^ adjustment $%@#^% what the hell did I do!!

[Guest]

So .. I am sure that there are others here like me that have a hard time leaving well enough alone. oh it can always be one minuscule bit better ... yes let me mess with it some more .. yea that's it its almost there ..... until I screw it up!

I decided a couple of weeks ago to reclean my carbs since I was having trouble getting the bike to idle well and I knew I could do a better job than I did the first time 3 months ago. I ordered a new throttle cable and new airbox to carb clamps.

Put it all together and except for a little adjustment of the idle screw underneath it was pretty good. I broke out my nifty new carbtune and did the sync and happy day. Took it out for a 55 mile ride .. no worries idled great and pulled right up to 7500 rpm with no hiccups.

Took the wife out couple of days after that on a super hot day and went about 40 miles. All good. I changed my oil to 20w50 and my idle dropped a little but actually brought it more inline with what it should have been. Still fine.

Then I got an email from Dynatek suggesting a gap of .32 for my setup and decided for 10 bucks I would buy brand new plugs. I put in new plugs when I started three months ago with this adventure but they have been run rich, lean and everywhere in between and adjusted 8 ways to sunday since then so I figured why not splurge.

Gapped my new plugs .. did nothing else. Bike has been sitting for 2 days. Went to take it out this morning. Stall. I adjust the idle screw under the carbs as its idling to low and get to the first corner and its at 3000 rpm. At the light it will drop down to 1800 on my tach but if I blip the throttle it hangs then slowly drops. I changed NOTHING else but the plugs.

Get home and pull the plugs and they are dead man bones WHITE and ashy. Alrighty .. to lean. I figure since I increased the gap I must have needed to readjust the carbs to allow for more gas ... Right??

No way to get the bike to idle without hanging up or stalling so I pull the plugs and regap them to .27/.28 ish. I start the carb mixture screws at 2.5 turns out and hooked up my carbtune again and made the slightest adjustment but they are in sync. I burned the flesh off my hand trying to adjust the idle screw under the carbs because no matter how I adjust the mixture screw I either get stalling or hanging up when I blip.

5 hours later .. and I have to stop.

To get consistent high rpm my 1 carb likes 3 turns my 2 likes a heavy hand with almost 3.5 and my 3 likes 2 3/4 the 4 doesnt seem to effect the machine much in either direction so I leave it at 2.5.

Should I make all these settings and then adjust the idle screw under the carbs? I should add that when I pulled the old plugs .. you know the ones that were in the bike when it was working great .. they were all a beautiful dry tan .. sigh .. why couldnt I have just left them alone!
Alex

[hannibal]

Put the old plugs back in...

You sure you tightened all the airbox to carb boots?

[BigD_83]

Put the old plugs back in, reset the A/F mix and the idle control to as close as what you had it before, and see if it runs better. When it does, have a beer.

On #4 A/F mix, the tips can break off and lodge in the circuit, but you'd probably have noticed something amiss, like a broken tip when you cleaned the carbs.

[TxGSrider]

The plug gap should have no effect on the mixture. Now it they were opened up too far they could foul and appear to be rich, but that's not what seems to be happening.

It sounds like maybe you got some crud settling in your carbs and may need to clean them.

[Boriqua]

Maybe a crazy thought .. the mixture screws have the spring followed by the metal washer and then closest to the tip a rubber washer. when I pulled the carbs apart a couple of weeks ago the screw, spring and metal washer came out lickety split but I had to fish the rubber washer out with a thin wire. Is it possible that by backing out the screws several times while adjusting that the rubber washer is partially blocking the hole? Guess I might be removing the carbs again .. I am like an EXPERT now.

[Boriqua]

The plug gap should have no effect on the mixture. Now it they were opened up too far they could foul and appear to be rich, but that's not what seems to be happening.

It sounds like maybe you got some crud settling in your carbs and may need to clean them.

No quite the opposite .. the new plugs were ashen white so some how something got way leaned out.

[Nessism]

It's normal for the plugs to look white until you get some mileage on them.

[hikermikem]

Are you certain the vac sync ports are sealed & not leaking? Vacuum line isn't cracked or disconnected? Choke isn't hung up?

Very odd it was running well, then not.

[Steve]

In the midst of doing all this work and removing the carbs multiple times, have you ever inspected/replaced the o-rings on the intake boots?

If you haven't, you should know that is a very common cause of the exact symptoms you are experiencing. A simple message to cycleorings.com and the transfer of just a few dollars will fix that quickly.

While you are ordering the o-rings, be sure to also get the stainless bolts that hold the boots in place. The stock screws will probably be damaged when they are removed, so install new, better hardware.

.

[hikermikem]

In the midst of doing all this work and removing the carbs multiple times, have you ever inspected/replaced the o-rings on the intake boots?.

This is one of the models that doesn't use o-rings at the head... the intake ports are cast into the head. The rubber boots use clamps on both sides to seal.

To Steve's point though, make sure those boots are not rock hard or split, and the clamps are tight.

It does sound like you have an air leak somewhere

[mmattockx]

Went to take it out this morning. Stall. I adjust the idle screw under the carbs as its idling to low and get to the first corner and its at 3000 rpm. At the light it will drop down to 1800 on my tach but if I blip the throttle it hangs then slowly drops.

That is an air leak about 98 times out of 100.


Mark

[JJ]

That is an air leak about 98 times out of 100.


Mark

At least 110 times out of 100.

[TxGSrider]

I actually think its more odd that it waited until AFTER you took your wife out for a ride. That kinda thing usually happens to me after I convince my wife to go for a ride. So in some way, consider yourself fortunate. lol

[Deuce]

No help here, but your story-and the way you wrote it-made me chuckle. It sounds like me. Great attitude for what I'm sure is a very frustrating situation. Good luck!

[Nessism]

Another bit of maintenance you can perform is to remove all the plug caps and check the resistance. They unscrew from the wires. Standard resistance is 5k ohms. If the caps check out snip off 1/2" of wire from the leads and screw the caps back on. I mention this because it almost sounds like your bike is randomly dropping a cylinder.