Tyres

[hatman]

Please tell me the correct working temperature range of tires. For example, kc3?

the most go kart tyres are working best at temp range of 43 - 54 Celsius (110 - 130 F).
Soft compounds favour higher temperatures and hard achieve lower temps. The rule "the softer tire the more grip" doesn't tell always the truth because in some cases the softer compound may go beyond the optimal temp range and the tires will start to lose their grip. A general rule is that you may go as soft as you can go near the above limit (approx 54 C) to get the best from your tires. Another big parameter is the pressure. The higher the pressure the more the temp rises, so if you are in qualifying you put a very soft compound with high pressures and in the race (15-20 laps) you run a harder compound (in order to last longer) with lower pressure. After the race you take the hot pressure of the tires (you must see a difference of 1-2 psi) and the temperature across the pattern. If the inner is about 1-3 degrees higher than the outer then it's ok. Some example to help you..

(Outer-Middle-Inner) : 41-42-43 = too low temps, try a softer compound or increase the pressure
                                    47-51-49 = good overall temp, lower the pressure
                                    46-43-48 = good overall temp, increase the pressure. If the overall temp exceed 54 then try a harder compound
                                    49-51-52 = just about the right compound and pressure

i'll try to make a review for tires in the next days to show the differences in the 12 different compounds in KRP. But i need time by then

[nmpcs]

Another excellent post.
Your tha man, hatman 

[The Iceman Marco]

It's much easier, just look at the pressure on the end of the session. When it's between 0.90 and 0.95 bar, it's good.