Can't keep 550T running

[Guest]

I have an 80 550T that I can't keep running. I did a valve adjustment, cleaned the carbs (the proper way) cycleorings, bench synched (haven't been able to vaccum sync yet), floats set properly to 22.4, the whole 9. It has pod filters on it with stock exhaust so I got a dynojet kit, installed it, bumped the main jets up from 92.5 to 102.5. Bike will crank and crank but not start. When I choke it, it will crank for a bit, then it'll fire up. I'll back off the choke, it'll run anywhere from a few seconds to a few minutes, and die. I bumped the pilots up from 40 to 42.5 to see if it would change but to no avail. It sounds like a classic clogged pilot circuit but I don't believe it is. Here's where things get interesting.

If I try to turn it over with the choke off the first time it hits it sounds like it wants to start (starts for a split second and then dies) and then just puts as the starter turns over. When I choke it again to start it up when the bike is warmed up, it doesn't start instantly and takes a few cranks to go. Now a warm bike I would assume would start instantly on choke if it was a pilot circuit problem. This is what's making me think it's an electrical issue. I tried to pull a plug wire off while it was running to check to see if it made a difference and I got a pretty big shock; bigger than I got from any of my other bikes. I cut a 1/4" off the plug wire, reset the spark plug caps to see if it made a difference but nothing changed. I tested the voltage at the coils: one as 12 and one is closer to 11. I'm thinking a coil relay mod but I wanted to double check to see if the low voltage to the coil would cause the hard starting or should I look elsewhere. Thanks in advance.

[tom203]

Try dropping idle stop screw as low as it can go- just so you think that it's barely "holding" throttle plates at all.

[overboostin]

Try dropping idle stop screw as low as it can go- just so you think that it's barely "holding" throttle plates at all.

Hey Tom, long time no talk. Hope all is well. I've tried messing with the idle screw as well with no success.

[tkent02]

I'm thinking a coil relay mod but I wanted to double check to see if the low voltage to the coil would cause the hard starting or should I look elsewhere.

To test it, just put a big fat jumper wire from the battery + to the coil. If that doesn't do anything don't waste you time on the relay mod, that ain't it.

Sure sounds like a clog in the carburetors to me.

[overboostin]

To test it, just put a big fat jumper wire from the battery + to the coil. If that doesn't do anything don't waste you time on the relay mod, that ain't it.

Sure sounds like a clog in the carburetors to me.

thanks ill try that tonight

[tom203]

Happy 4th ! Nice growing stable you got there. If wiring coils direct doesn't do anything, must be gunked up pilot circuits. If it sorta runs above idle, have you tried the Italian tune up? Find some long steep downhills, get it up to speed and shut throttle to raise intake vacuum on those nasty little pilot holes.

[ukjules]

I am sure this is not gonna help but I'll say it anyway. On my GS 550 after a head or carb removal for some work I can "never" , "never" start my bike without spraying easy start into the airbox without the filter in. It does exactly as you state ! Spraying easy start in gets it going within a minute and then never an issue until I pull it all to bits again. Also vacuum pipe to the carbs ? Is that in place , intact ? Probably no help but these two things almost made me pick up the sledge hammer.