I'm planing on putting in a sweet pick-up into my starter guitar(Yamaha erg 121c), along with some thicker strings and using it to play in C-standard. It's not built for that, so I'm just wondering if that's gonna warp the neck or something like that?
what gauge are the strings? it should be able to stand anything up to 11 gauge strings without any neck warping issues. just remember to readjust your action and intonation
it shouldn't, as long as the strings aren't to thick try 11-56 or so
thx for the help guys btw i was thinking of putting on some Ernie Ball "Heavy bottom" string 10-52
It'll be fine, you'll just need to set up the guitar properly for it. This may include a tiny tweak to the truss rod and will definitely involve re-intonating the guitar (you just need a tuner and a screwdriver - should take about twenty minutes to get it exactly in tune). If your guitar has a vibrato bridge (Strat style trem, Floyd Rose style double locking, whatever) then that will need adjusting as the increased string tension will be throwing the bridge out; you'll need to tighten the springs a bit in the back of the guitar to even out the tension. You may find you'll have to raise your action a little bit too.
You should be able to put any commercially available strings on. If you're making a big change it would be good to have the guitar set up.