wemoto
you can choose what year then the sprocket sizes. the standard SVs 15/44 is 108 links and 15/45 is 110 links. if you go down 1 tooth on the front (not recommended as it eats the chain block) its like going 3 teeth up on the rear and its a 108 link chain. going up 1 tooth on the front (recommended as it takes the chain further away from the chain block) is like going down 3 teeth on the rear and you need a 110 link chain.
going down 1 tooth on the front will give the bike a lot more pep but its recommended to go up 2 on the rear for almost the same effect at the expense of having to be a bit more gentle on down shifts.
going up one tooth on the front will make the bike a bit lazy but it feels a bit more 'grown up' at the expense of carrying a we bit too much speed into corners and i find having to do another downshift on tight corners just before corner entry.
the standard gearing 15/44 i would say is a perfect combination adding a 45 rear gives the bike a little more pep and gets you there faster.
gold chains help with keeping the plates from rusting and thats about it.
chain life is only as good as the person maintaining them so if your lazy like me get a scottoiler.