dying at idle

borjawil · Posted: July 13, 2009, 12:14 pm Post subject: dying at idle

Ok so i used the following manual to tune my carbs.

www.amckayltd.com/carbguide.pdf

ive set my screws at 2.75 turns out sincve i have non stock jets. tried to hear or see a difference on the tach when changing the mix screw for each individual cylinder. didnt see anything really so i left them there. i suppose ill go with the spark plug readings to figure it out.

i set the right and left cylinders to 1000 rpms and put both plugs back on and it starts at 1500.

when i set these idle speeds am i doing it at full choke or closed? because if i have full choke, bike starts on one kick, and it idles at 3000. im guessing thats high. half choke its at 1.5 as well as no choke.

i did noticed though that ill get a sort of "bump" in power when im going(only run at slow speeds through the neighborhood. quick little bump then back to normal. might get a couple of em.

im guessing due to air leak or maybe an passage in the carbs being blocked.

im guessing my right carb as it backfires sometimes on that side at start up or would. didnt hear it this last time after i retightened the carb manifold on both sides.

Also my bike has recently decided to die at idle. I can start it and itll idle fine. I get on shift down to first and go. then when i come to a stop with clutch pulled in itll just die. doesnt sputter or anything. just stops.

Any help on my baggage would be great. thanks!

xsjohn · Posted: July 13, 2009, 3:04 pm Post subject: Re: dying at idle

If it were mine I would suspect the pilot circuit is not clean........and a road test at operating temps on light cruising throttle is the best way I have found to set the mix screws.....black being 1/3 or so up the side of the electrode ....seting eachside independently...and a very slight hint of soot on the plug....as seen on the finger....tweek the mix screw and recheck after a few miles and reset as necessary........

xsjohn

borjawil · Posted: July 13, 2009, 4:07 pm Post subject: Re: dying at idle

hmmm...i was thinking it was the pilot circuit but it didnt do it before...ill reclean and check. gotta wait for new seals for the camshaft, one ripped.

thanks for the help Smile

xsjohn · Posted: July 13, 2009, 7:14 pm Post subject: Re: dying at idle

The fuel has to come out the 3 tiny holes in the throat.......and carbs that have set for a long time can be pesky....try using a small guitar string bent in an L to gently probe the 3 holes as you spray and cover the other holes with your fingers to increase spray pressure......if the spray is coming out the 3 holes then most likely they are clear...........and I asume you went to a 45 pilot and 2 3/4 turns is about the ballpark......setting each side at cruise (operating temps) for the black at 1/3 the way up the electrode....I use a 46 pilot which seems to be better on high speed decel and cruising....but just a bit of a turn is a lot from being correct which on a larger pilot is also noticed with the 45......

and set each side mix screw independently as to plug color (at cruise)noticing the side of the electrode..that is hard to do without R/L needles which I make.....and..1/3 is good and the right is always a pain in the ass since it runs 25 degrees hotter requiring more fuel...and the temptation to over set the right to make up for the extra right side heat is there..... what would I know.... Laughing

Remembering this was the world of the epa....every stage was leaned to pass the standards of emmision..........not caring about performance or longevity of the engine.....but once overcome what lovely carbs the really are............

BUT...for a cruiser at 250-260 cylinder temps is crap in the summer......and everyone laughs a me for 8-1....actually the lauggh is on them because at those timps the HP is about the same without the heat and racket.... Laughing

.... ...........and no one has spent the time to measure to discover how these dissapate heat..........to bad..... Laughing

xsjohn

borjawil · Posted: July 13, 2009, 9:26 pm Post subject: Re: dying at idle

great. thanks again john. and sometime in the fall ill have to take you up on the needles and 8-1 adjustment.

xsjohn · Posted: July 13, 2009, 9:34 pm Post subject: Re: dying at idle

Well get all the other things together I mentioned.........8-1 really pays off great in the summer........and everyone thinks I'm a nut case too.....could be maybe they can't ride them far enough to find out different...or spending all their time putting them back together...or fixing the last PO's attempt to ride it somewhere..... Laughing

...imagine every 15k if they are real lucky or less and no waranty and pure torture... Laughing

..don't hop it up....then your problems have just begun for double sure....then again Obama will help out..............

Laughing

xsjohn

borjawil · Posted: July 14, 2009, 9:23 pm Post subject: Re: dying at idle

haha...so after i reclean the carbs 5 times today, an old theory i had yesterday came back...what if its the battery? everytime i squeezed the front brake it would die...but the rear brake doesnt have a switch attached yet. and when i hit that it didnt...i feel like i wasted a day, but at least i know my carbs are clean!

So charging the battery tonight. hopefully that was the problem!

wally · Posted: August 30, 2009, 3:39 am Post subject: Re: dying at idle

sorry to jump in BUT On the cafe Im running 46 pilot standard 132.5 mains with foam pods Pilots at the moment are at one & a half turns on both hows that sound should I go to 135 maind as well
After a lot of cleaning & recleaning & one of my problems i had was the three holes on ride side were blocked I may have it running good now
I hope Touch Wood

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