thunderace wrote:You won't need 7s in the UK. Apart from which, have you tried buying any? Rocking horse poo is easier to get.

CR8s you can get all day long but be warned, they're around £6 per plug TRADE price.

For many years, auto makers and mechanics recommended hot spark plugs for vehicles that primarily were driven slowly and for short distances, and cold spark plugs for automobiles driven on long distances and sustaining high speed highway use.

To get a true plug color reading you must run the engine,on a level road, at the throttle setting that you want to test, for about a mile, then kill the ignition, pull the clutch in and coast to a stop. Then pull the plug and look at it. This could be a real thrill on most of the newer street bikes.

As the engine ages and more oil gets past the rings a hotter plug may be in order. If you ride at low speeds all the time a hotter plug will keep the plugs from fouling. If high speeds are your thing, a cooler plug may be just the ticket. Don't be afraid to pull that plug out and give 'er a read!