General Bike Maintenance

i bought a 1986 gsxr750 to replace my poor lost TL (i know some of you may think thats a step backwards but its 190kg with 100bhp at the back wheel, i'm not complaining), and its been going great till just a couple days ago. well pretty much yesterday though sunday was a little glitchy. feels like its running on 3 cylinders, maybe even two sometimes, pulled out sparkplugs yesterday, they're brand new. mechanic mate said, might be distributor leads but i'm hoping its not cos it turns out they're ...

i assume its some kind of breather but i really don't know..any TLS riders, i'd love some help!

my battery keeps crapping itself..like, it'll go great for a while, but it'll wear down and then die completely. i'm currently running my brother's chopper battery in it and he wants it back..
i've been told perhaps i'm running the wrong ampere/hour (old battery was 10amp/hr and current one is 7 amp/hr) but what i know about electronics is smaller than an ant shit..
anyone else experience this problem? i have spoken to a few that say it's just what TLs do..any ideas of how to remedy ...