Weird problem still with my idle speed

[BamaDrifter64]

Had put a Pingle manual petcock on my Std in order to make a weekend ride b/c my OEM petcock had started leaking.  It was doing fine, but didn't ride any in February and most of March due to weather and obligations.  Started it sometime in March and it was running fine, but was leaking gas again.  Ordered a new OEM petcock, fuel line and petcock vacuum line and installed the new petcock and fuel line this week.  When I started it up, on full choke it would only run 1000 to 1200 rpm and when you took the choke off, it would drop anywhere to around 400 to 600 rpm and continue dropping slowly to where it would die.

Today, I took the tank off again and checked the air box tubes to the carbs to see if I had incorrectly attached them.  The only one close to being suspect was the #6 connection where it looked like the back lip might have rolled under a little bit.  Fixed that, re-tightened everything and changed out the petcock vacuum line while I had it apart.  Put the tank back on, put full choke on and started it up.  Went up to 2000 rpm right off the bat and I shut off real quick b/c I was in an enclosed garage.

Buttoned everything up, got it off the lift and out of the garage.  Started it up and it's doing the SAME THING!  All I did after starting it on the lift was put the side covers and the seat on, which shouldn't have changed anything.

Here's how it runs now.  With full choke, idles around 1000 to 1200 rpm.  Give it gas and it revs right up.  RPMs do not decrease at idle on full choke.  Take the choke off, idle decreases to 400 to 600 rpms.  Give it gas and it stumbles a little and then rpms increase.  If you let it idle with no choke, rpms decrease and will drop to about 200 rpms and after a couple of surges to about 300 rpms, will stall.

Any ideas?

Dave

[Chrisj CMA]

If you can get it to idle w/o the choke try increasing the idle adjustment to 1000 without the choke and see what happenes

[Hoser]

If you can get it to idle w/o the choke try increasing the idle adjustment to 1000 without the choke and see what happenes

+1 800 to 1000 is normal without choke and warmed up.  Hoser

[BamaDrifter64]

Ok, here's what I did.

Increased idle to 800/900 rpm.  It kept that speed, fluctuating back and forth about 100 rpm.

Took it for about a 10 mile ride.  No power.  For lack of a better description, the exhaust sounds "hollow".  When I purchased it a little over a year ago, the carbs had just been cleaned and synced and it ran like a scalded dog.  Ran so hard I wouldn't FOT in the 1st 3 gears because I was afraid the front tire would come up.  Not running anything like that now.  Goose it in 5th and it doesn't move.

Turning around to come back home, the idle speed was 2K rpm and wouldn't come down without me turning down the idle manually.  I'm stumped.   

Dave

[big bear craig]

Do you have vacuum at the petcock?  Tank vent hose kinked?  Intake manifold vacuum caps ok?

[BamaDrifter64]

Brand new OEM petcock, brand new petcock vacuum line, vent line looks ok, haven't messed with any vacuum caps.

[big bear craig]

I just went through a different problem with my bike, so I know how frustrating this can be.  Your problem is probably something simple.  Go back and check everything you did.  Check all connections, make sure there isn't a kink in the tank vent or the vacuum line to the petcock.  Is the fuel line running down to the carbs so gravity can supply them?  Check the fuel line for a kink too.

[ValkFlyer]

Check to see if you exhaust manifold bolts need tightening.  Also, check your intake manifold gaskets for leaking.

[Patrick]

I too would suggest opening the drain screws and check for proper fuel flow.. It also sounds like you have a fuel quality issue,, it sounds as if the fuel has been sitting around for awhile and you now may have some varnished jets..

[BamaDrifter64]

I too would suggest opening the drain screws and check for proper fuel flow.. It also sounds like you have a fuel quality issue,, it sounds as if the fuel has been sitting around for awhile and you now may have some varnished jets..

It only sat for about a month and a half and when I started it back in March and had the fuel leak, it ran fine....

I'm going to put the Pingle back on and see how it does...could be that maybe the new OEM petcock has a problem...at least I can do that before I tear into taking the airbox off again...just plug the vacuum line and hook up the fuel line and vent line....

Dave

[longrider]

I'd be checking you fuel line from the petcock to the carbs.  Most likely is a bit too long and has a kink in it and is starving the bike

[roadmap]

dirty leaking gas i bet you need a complete rebuild. i couldn't get my bike to run either my petcock was leaking cleaned the carbs put float seats on and slow jets mine the slows were not clogged. still could not!!!! get this to run right.  till i broke down and did a complete carb rebuild something was clogged nothing i could see. it was a touph one to figure out. the gas is bad now and in the future it going to get cheap (made) if all else fails let each carb soak 12hours then do another one put a new o-ring kit on

i had to i bet you do too 

[BamaDrifter64]

Here's an update of what I did tonight.  Started it up - full choke = 1000 to 1200 rpm, no choke = 600 rpm.  Increased the rpm to 800 - 900 rpm with no choke.  Got it on the lift and totally disconnected the vent hose.  No change.  Visually checked the vacuum hose to petcock - no kinks.  To be sure, manipulated the hose several times while running = no change.  Took the tank off and removed the new OEM petcock and replaced with manual Pingle.  Golf tee in vacuum hose.  Started bike and stayed about 800 - 900 rpm.  I have a thermometer dipstick and at 120 degrees, the idle increased to 1000.  By 140 degrees, idle was up to 1500 rpm.  Turned it off as I knew there was no improvement.

Any ideas?

Dave

[R J]

Get the bike to full operating temp, set the idle to 800 or 900 and then leave it alone.     You do not have a problem, it is just normal nature for the bike when warmed to full operating temp.

You don't want to mess with that idle adjustment when it is cold or in the middle of a warm up procedure.

[BamaDrifter64]

RJ, if I do that, the rpms at full choke will only be about 1000 - 1200 rpms and at no choke less than 600 rpms and will decrease until it stalls.  There is some kind of problem because it wouldn't do any of that before.

Dave

[Ricky-D]

The question needs to be asked.

What has been done to the carburetors?

Changes, modifications, whatever!

***

[BamaDrifter64]

No mods to carbs.  Carbs had been cleaned and synced a year ago.  Ran like a racehorse.  Guess I will take the airbox back off and re-install everything again.  I have a desmog kit that I was going to put on my I/S when I got this one running, might go ahead and put it on this one.  That should eliminate any vacuum problems if I keep the Pingle on.  Will put a bottle of Techron in it too to be on the safe side.

Dave

[Ricky-D]

With everything stock in the carburetors and no vacuum leaks I feel most idling problems can be attributed to a poorly synchronized carburetor system.

When the problem persists I would then advise a compression check on the motor.

***

[BamaDrifter64]

Interesting note - started the desmog tonight.  Took my chrome spark plug covers off and noticed that it looked like the #6 inake manifold had been leaking on the block.  Have to take the 1, 3, 4 & 6 intake manifolds to do the desmog, so since I had replacement o-rings available, figured I would go ahead and replace them all.  #6 had NO o-ring!  Before I bought the bike a year ago, the carbs had been "professionally" rebuilt and synced by a dealer.  Guess they couldn't count past five.

Dave

[Bone]

Makes you want to check your carbs sync.

[MP]

RJ, if I do that, the rpms at full choke will only be about 1000 - 1200 rpms and at no choke less than 600 rpms and will decrease until it stalls.  There is some kind of problem because it wouldn't do any of that before.

Dave

I am with RJ on this one.  You ARE setting the idle incorrectly.  I do not know if you have another problem.  You HAVE to set the rpm at 800-1000 when the engine in FULLY warmed up.  Do NOT set it when cold. 

DO THIS FIRST!  Then, leave it alone, and work on the other stuff.

Mine will do the same as yours when cold.  With idle set correctly, if I take the choke off when it is still cold, it will slow down and die.  NORMAL!

MP

[BamaDrifter64]

MY BIKE IS BACK!!!!!!!

Spent the day today desmogging the bike, putting new o-rings on the intake manifolds, then putting things back together.  By a fluke, I found the culprit for my earlier problem and still scratching my head over it.

The inside wired connector (closest to the frame) on the #1/#2 coil had come off.  Don't know how, but it had and was hidden by the outside wired connector.  Bike runs really good, just have to tweak the carbs back to what they were.  While I had the manifolds out, I ran the carb adjustment screws from 1.5 turns to 2.25 turns.  Now it's too rich, getting a faint blue smoke out of the exhaust.  Going to adjust back closer to 2 to 1.5 turns.

Thanks for everybody's help!  

Dave

[Patrick]

I'm surprised you weren't complaining before .. You found too many problems,but, I'm glad you figured it out.. Who would have thought you were running on only 3 cylinders, a front coil lead off and no o-ring on #6.. I bet your surprised to see how good these monsters run when everything is as it should be.. If the pilots were set at 1.5 turns and 2.25 is too rich then it sounds as if you have 38 low jets[ if you mentioned this before I don't recall it].. 2.25 for 35s and 1.5-1.75 for 38s seems about right.. Once you reset the pilots consider a carburetor sync, since you've found all these problems who knows were the idle stops are set..

[Ricky-D]

If you're trying to say that it is strange, not recognizing the motor is only running on a few cylinders, I would have to agree.

***

[BamaDrifter64]

The only thing wrong was that a wire was off the coil for the #1 and #2 cylinders...don't know where the "running on only 3 cylinders" came from.

Dave

[Patrick]

Front coil runs Cylinders 1 and 2.. No o-ring on #6 pretty much kills that cylinder with a huge vacuum leak..

[BamaDrifter64]

It was running like a raped ape before the problems...if the vacuum leak on #6 was affecting it before the coil problem, you sure couldn't tell it.  Anyways, got it all fixed now.