So my bike is still in the shop...I guess I should say friend's acquaintance's garage due to the problems it had when I first got it.  I eventually concluded (after cleaning out the carbs 2xs) that it was only running on one cylinder (problems w/acceleration and dying out on me).  The guy who is working on it is thinking valve problems so I gave him the go ahead to check/adjust them...figuring it may be a little too much for me to take on -- i'm new to this motorcycle stuff.  However, after searching through numerous posts it seems the problem could also be electrical (I replaced the spark plugs before I sent her away and still had problems).

My question(s) -- could the valves have caused this lack of power and my bike dying with that chug chug feeling, or is checking/adjusting them simply a waste of time (and money)?  do you think it could it solve the problem?
Also, should I ask him to also check the electrical stuff too or should I just do that myself?  My first thought is ignition coils and I just read something about ignition rotors.  I'm a noob at this and would have to get a multimeter, but want to know if it really is that easy to do electical work on a bike?  Keep in mind that with all your help I did clean my own carbs! 

Any advice would be appreciated, and for the record (and to keep me in your good graces) I didn't take it to the stealership itself...but to someone who works for one and wrenches on bikes in his free time...i.e. cheaper!  But...it's been like 2 1/2 weeks

i havnt read any of your previous posts but it sound like one of your coils is buggered or has a wire loose, the easiest way to check this is change the coils over from left to the right and vise versa
have you checked to see if both plugs are firing by holding them to the side of the engine(make sure you wear gloves or just hold it in place with a stick)
if one isn't firing or the spark isn't a bright blue colour its more than likly that it is that particular coil. i doubt very much it would be the valve clearances.

i did the spark check before i dropped it off, and did see a spark from both sides.  i didn't notice if one was brighter than the other, though.  should i just phone the mechanic and see if he'll check the coils?  or is there something more specific i should say?

Off hand, I'd bet it's electrical, not valves.  Had the same problem earlier this year when it was very, very damp in my garage; dew on everything inside the garage and out. 

No need to switch coils to see if this is the problem when one cylinder is cutting out.  I reached down sitting on the poorly idling bike and pulled off the right plug cap and the engine stopped.  Put cap back on and restarted and pulled off the left plug cap and nothing happened, idle speed didn't even change.

High tension lead was shorting out where it goes into the left coil and I just tightened it up and tightened all other connections and it's been fine all summer since,

I too checked the spark by pulling the plugs and putting them in the caps and grounding them against the engine.  Both plugs showed spark while cranking this way, but running under load the spark took the path of least resistance across the coil to ground.

It could definately be electrical, but if it is valves it seems like doing a compression check would tell you if something is screwy in that department for a lot less time (time=money) than pulling the valve cover to inspect the valves. If the compression is good, the valves can't be too far off.

thanks for the responses.  i checked the compression prior to sending her in and it seemed that the left side was lower (i had to hold the thing on cause i didn't have an adapter to fit).  but...i also tried the 'pull spark plug cap trick' and it cut out when i pulled the left.  do you think this could mean both valves AND electrical?  how rare/lame is that? 

either way, i left a message for him to also check electrical.  you all think there could there be any other reasons?  the mechanic said that he thought it was a 60% chance it was the valves...that doesn't sound very optimistic...