Topic: 550 runs fine in neutral, bogs when in gear?

[Mattzilla]

So, I was thinking that I had a carb problem, but maybe not (though they likely could use a cleaning and some fresh gaskets)... I bought her, rode her home, took care of the paperwork and bombed around town a couple of days, maybe eighty miles or so, hit 90mph a couple of times, she seemed quite willing. I was a happy camper. a week later I ride her to work and she slowly goes down to three cylinders tyen two just as I'm pulling in. When leaving, it takes me about a half hour of kicking to get her to start as the battery had died and she limps home, occasionally feeling like all four have jumped to life. I swap the battery, and same bs. Swap the regulator, same bs. I swap the plugs, same bs. I get new coils and same bs. She revs up heartily in neutral but starts crapping out as soon as I click in to gear. The fuses look good, though a p.o. had stuck a wire spliced from the taillight to one of the fuses clips (eek!).

Does this dieing-only-when-in-gear business have a known regular cause, or is it just time to tear out all of the wires and redo the whole thing with fresh copper and hope for the best?

[flybox1]

First, download the shop manual for your bike and start completing every item in the schedule 3000mi maintenance, including a good carb clean, and a vacuum sync when all listed are done.
Second, go through all your electrical connections. they need attention.

[Duanob]

Also check your fuel flow. Start at the tap and see if you have good flow. Could be a partially clogged fuel tap or line.

[Deltarider]

Do you have a multimeter? Does the bike charge at all?

[ekpent]

Bikes can run and rev when in neutral but the big test is when they run a 'load' which is in gear under way. Sounds like you are swapping in parts and pieces. Best thing is to start with a very clean gas tank and carbs. That's one part of the equation. Next is spark which would be good clean points set right, new plugs, working condensers all timed up, good wires and caps and a good battery. If all those are going good and wiring has no major snafus then you are on the right track. You can check compression but those are the basics to get you to a point you can fine tune. Got a picture of your bike for us to see ? 
   What's stock and what's not ?
PS-Welcome to the forum-- Eric

[Fritz]

Do you have a multimeter? Does the bike charge at all?

+1

To me your symptoms look like a weak battery. The smaller Fours are notorious for their underpowered generators. If you do not keep the revs above 3000 most of the time, the battery will not charge. A weak battery will cause a weak spark - fine for idling but not enough for riding.
So you might be on the right track. But most likely you will not need to rewire the bike - if it's not been hacked into too badly. The connectors corrode and a proper cleaning (including fuse clips) should do the job.
Measure voltage at the battery. Check that no battery cells are dry. If the voltage is below 12.5 Volts you should check the performance of your charging circuit:
Download the service manual in the FAQ section of this forum and test the charging circuit as per the manual. Also search the forum for TT's AKA Lloyd advice on how to diagnose charging problems.

Cheers
Carsten

[phil71]

the symptoms look like a weak battery? I'm with Duanob here. It's fuel.

[Mattzilla]

for the sake of anybody else that gets this problem, I was a genius for not checking the oil (among other things) before kicking her over. I drained out the old stuff, swapped the filter and tried again- VROOOMM! I got to bomb around the cemetary a few times before the snow fell.