Loves the heat.

[Tri2Tri]

Had a long long blast in the 400 this afternoon. Running the best it's ever been including town traffic. Does weather conditions effect the Chims running?

[Milky400]

Without a doubt, use to make a difference to my old one. Although ran best in the autumn when the air was denser

[BabyDriver]

Strange cars usually run better when it's wet or damp

[Dr Mike Oxgreen]

All engines develop more power when it's colder, or when the atmospheric pressure is higher, and are at their best when both conditions are true!

It's all about air density. Denser air contains more molecules for a given volume of air, so each time a cylinder draws in a charge of air it's getting more oxygen molecules. The ECU can therefore inject a tiny bit more fuel to match. It's like having a slightly larger engine.

You should try flying a light aircraft from a low aerodrome on a cold day with high pressure. It's a triple whammy: the engine develops more power; the prop develops more thrust; and the wings develop more lift. The thing practically leaps off the ground!

[Tri2Tri]

Well the explanation makes sense with colder denser air, just wondering if I have something a miss as its running better in hotter less dense air...very odd.