Im just intrested to know, as its a long time since i bought any plugs for a bike. When i do, will the electrode gap be set already? based on the fact ive bought the right ones (code number)? or do i need to set it myself? may seem stupid but i remeber having to set each gap for my car as all the plugs where at diffrent limits????? just qurious? also what the diffrence between a 8, 9 and 10 plug (NGK)?