Tune it up.................seriously, with no other facts than that you get really nothing else. Does it have gas in tank? What about your petcock work? What if the caliper work has now got the caliper locking up the wheel to drag the motor down? How about oil in motor? Battery lost power? Don't expect an almost 40 year old bike to run perfect, it could be totally wore out.................could be 50 things easily wrong there.
You don't mention at all how it ran before the work, asking us to figure that out = kinda silly actually. Not helping yourself at all there.
Bike that runs like crap helped along to then run worse? Easily possible with thinking so basic it cannot work.
No insult intended at all with what I say next but there is a difference in intelligently asking for suggestions by your pre-weeding out common issues and simply asking us to dress children in the morning by asking for literally everything that can possibly go wrong. After all YOU are the one doing the work there. Asking the way you did begs us to choke you with a million different things that could easily waste every bit of your time. Not to mention a good chunk of hard-earned cash. Remember that you still have to think enough to weed out all the things we could possibly suggest, and I myself could come up with literally a hundred or so.
Having said all that, look at the plugs, they could easily all be fouled out from crap engine condition which was left unstated.
Compression check on motor, there is nothing so stupid as wasting time and money on something that is NEVER going to run correctly. I saw it all day long with cars when I used to be in parts. People do it on used bikes all day long and even worse and how it never enters the mind that it just may not run right regardless of what you do is way beyond me.
