Cool running center cylinder, GT550

durgam · Post by **durgam** » Tue Jun 08, 2010 1:25 pm

I need some help from the board. I ve mentioned this problem and before and I thought I had it solved. But its reared its ugly head once again on my 74' GT550

At Idle, and around 2000 revs my center cylinder runs about 150 -175 degrees cooler than the other two. The right and left are with in 5 degrees all the time. Its just the center cylinder

The timing is spot on, and I have cleaned the carbs numerous time after time. Ive got 102.5 mains, and 30 pilots. I did these when I did the pipes. My air screws are all out 1 full turn. This gives me better throttle response. The Bike is a turd till 3000, and hits real hard at 5300 revs all the way to 8000 plus.

Im asking board members if anyone had a set of known good carbs (74 and up Rack style) that I could borrow, to help diagnose my issues. Also maybe a set of coils, if this may be an erratic coil issue. Im at the end of my rope. The bike runs grweat otherwise, and I still ride it daily, but I know it can be improved upon.

Please, any help would be appreciated.

Coyote · Post by **Coyote** » Tue Jun 08, 2010 4:07 pm

Sorry. No spare carbs but I have a known good coil pack you are welcome to borrow.

Coyote · Post by **Coyote** » Tue Jun 08, 2010 4:14 pm

I got to thinking. This COULD be caused by a weak or leaking (internally) condensor. Try swapping them out and see if the 'cool' follows it.

Cliff · Post by **Cliff** » Tue Jun 08, 2010 6:33 pm

Durgam, what do your plugs look like? Are the left and right cyls. running lean or is the center cyl. running rich? Try balancing you carbs. first.
Follow the instructions on pages 38 & 39 in the link below.
http://www.3cyl.com/mraxl/gt/manuals/su ... /cover.htm
Cliff.

durgam · Post by **durgam** » Tue Jun 08, 2010 7:33 pm

I started swapping condensers earlier, but ran out of time, and now my boy is in bed, and im sure the bike will wake him up. Ill have to waitto maybe thursday to test it. If this doesnt work, I my try that set of coils. I appreciate it. Thanks

durgam · Post by **durgam** » Tue Jul 06, 2010 5:25 am

Swapping condensers did not help.