Lrp sphere help
 

I really have no idea what im doing in terms of gearing and at the moment my esc keeps getting stupidly hot and cuts out after about a minute or so, im running an lrp x11 7.5t with a 21t pinion and an 81t spur, anybody know what it could be?? Thanks.

You/we need to know the internal drive ratio of the car. The fact that it's an LRP is irrelevant.
Post in the manufacturers section (if you're running a popular car) or provide more details here.