throttle hang-ups and nonstarts

Barnfind

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colorado
I have never owned a motorcycle or worked on small engines, so I figured rebuilding a non-running 1982 Yamaha maxim 400xs would be a great place to start. According to the previous owner this bike sat in a garage for six years but before it sat it ran great. I went through the carb twice and have gotten the bike to run and ride. After my first time through the carb I noticed that the carb was flooding into the engine. I replaced the float needle and that seemed to solve that problem although it is a bit hard to tell since the oil already smells like gas, but the spark plugs are no longer wet after trying to start the bike. The bike is super hard to start and I often have to resort to roll starting it. If I can get it started I usually need to crack the throttle a bit and let it warm up, and i can't reve the bike or back off the choke without it dying. Once it is warm it runs okay but the throttle tends to hang-up and have a bit of a slow response. I am looking for advice on what to do my third time going through the carb. I have not checked the float level, balanced the carb, checked the timing or done a compression test on this bike. I am hoping someone can point me in the right direction of carb tuning or general engine advice.
 
I am wondering if I have not been starting the bike correctly. I have been avoiding the prime setting and starting it on run. Today I started it on prime and after minimal trys it started up. I put new plugs in it today and after running it for a little bit I noticed that the left plug had a lot of carbon build up while the right plug was totally clean. it seems as though the idle is still not there but over 3,000 rpms the bike runs great.
 
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