Well It Ran

[mrutah12]

WELL FINISHED INSTALLING NEW COILS TODAY WAS ALL EXCITED TURNED THE KEY ON HIT THE START BUTTON AND IT STARTED WITH JUST A HALF A CRANK OF THE ENGINE LET IT IDLE SO I COULD ADJUSTED THE AIR SCREWS SO I WOULD HAVE A SMOOTHER IDLE WITCH WAS FINE UNTIL I GRABBED THE THROTTLE AND CRAKED IT OPEN JUST A LITTLE NEXT THING I KNEW WAS IT JUMP TO 4 THOUSAND RPM AND I COULND'NT GET IT TO DROP SO I SHUT IT OF CHECKED EVERYTHING OVER AND COULD'NT FIND ANYTHING WRONG SO I OPEN IDLE SREW UP MORE AND STARTED IT UP AGAIN AND IDLE WAS NORMAL AGAIN SO I ADJUSTED THE SCREWS ONCE 1 &2 WHERE FINE WHEN I STARTED TO TURN # 3 THE RPM SHOT RIGHT BACK UP LIKE CRAZY SO I TURNED IT OFF AGAQIN AND PULLED THE TOPS OF THE CARB OFF TO LOOK AND SEE IF MAYBE THE DIAPHRAM ON NUMBER 3 HAD SLIPPED BUT IT HAD NOT SO I THOUGHT I WOULD CHECK THE NEEDLE SETITING AND THEY WERE ON THE 4TH GROOVE SO I PUT THEM ALL BACK ON THE 3RD GROOVE WILL PUT THEM BACK TOGETHER TOMARROW TOOK SOME PICTURES OF THE BIKE TO SHOW YOU ALL BUT I DONT KNOW HOW TO POST THEM ON THE FORUM CANT FIGURE OUT WHY IT DID THAT READ SOME OF THE CARB TIPS HERE GOING TO TO STRECTH THE SPRINGS A LITTLE TO SEE IF THAT HELPS CHECK DIAPHRAMS FOR HOLES DIDNT SEE ANY DONT KNOW WHAT ELSE TO CHECK

[TopCatGr58]

Hey Utah,

Sounds very much like your carbs need to be vacuum synched first! You say you are adjusting the Idle Screws?? There is only 1 idle screw, it's in the middle of the carbs, has a large thumbscrew handle to allow you to adjust the main throttle plate to increase or decrease the idle.

There are 4 pilot circuit screws on the top front of the carbs that are used to fine tune the pilot/idle circuit. There are 3 other screws in between the carb bodies, that are the vacuum synch screws. IF you are turning these, then you are actually possibly unsynchronizing them, causing your runaway idle.

You will probably need to pull the carbs and do a good bench synch first, there is a tech tip about this technique, but a variation instead of using the breadstick tie is to visually gauge the butterfly covering the last of the 3 holes in the upper portion of the engine side of the carb throat. That will get you CLOSE, but then you'll need to vacuum synch them. Then you can fine tune the pilot circuit for throttle response.
T.C.

[mrutah12]

SCREWS

I MENT TO TO PILOT CIRCUT SCREWS ALSO FORGOT TO MENTION WHEN IPULLED NUMBER 3 DIAPHRAM APART IT DIDNT HAVE THENORMAL SPRING THAT BELONGS THERE SOMBODY SUBSTITUTED IT WITH A SPRING FROM A BALL POINT PIN THE CUT THE SPRING IN HALF AS I DIDNT HAVE THE REGULAR SPRING FOR I HAD TO PUT IT BACK IN WILL CHECK MIKES XS SITE TO SEE IF HE SELLS THEM COIL INSTALL WASNT HARD AT ALL TOOK OLD ONES OUT PUT NEWS BACK UP INTO PLACE NO MODIFYING AT ALL EXCEPT FOR THE WIRE ENDS BUT OTHER THAN THAT IT WAS PLUG AND PLAY THANKS TC FOR THE INSITE ON THE COILS AND YOUR HELP

[HobbyMan]

sounds like that is part of your problem. These are constant velocoty carbs and spring pressure will make a difference. The air going in underneath the diaphram must lift the needle by providing enough force to overcome gravity and spring pressure. less spring pressure will change the amount of travel at different rpms. It does sound like your sync adjustments are way off also.

[mrutah12]

well it ran

THANKS FOR CONFRIMING MY SUSPISIONS I WILL ORDER A NEW SPRING IF I CAN FIND IT FROM MIKES XS I WILL SEE WERE I CAN FIND A CARB SYNC TOOL I DONT HAVE ONE OF MY OWN I JUST HAVE TO REMEMBER HOW TO USE THEM ITS BEEN OVER 8 YEARS SINCE I USED ONE CANT BE THAT HARD TO USE WONDER WHAT ONE WOULD COST TO PURCHASE? THANKS

[HobbyMan]

There is a tech tip on how to make your own or you could go and buy one. Does anyone know where Hippy Dave got his? I have a mercury sync but mercury can spill and I think it may even evaporate. Its a relatively easy process.

[cajun31]

Carbtune

Try to win this one on ebay http://cgi.ebay.com/ebaymotors/Morga...spagenameZWDVW or you can go to the web site where they are sold http://www.carbtune.com/ .

I own this one and it is great and you don't have to worry about sucking the mercury out of it as there is none.

[cajun31]

try this one

http://cgi.ebay.com/ebaymotors/Morga...spagenameZWDVW