Jetting for IAME kart engines

The simplest way to get the most out of your IAME X30 or Leopard kart engine. And a logbook where what worked stays written down. Get it before your next race weekend.

Works out the carburation of IAME kart engines with a diaphragm carburettor, from the real temperature, humidity, atmospheric pressure and altitude.

ENGINES IAME Leopard RL, X30 Senior, X30 Junior and X30 Super 175, with Tryton HB27 and Tillotson HW-27A, HB-10A and HL-334AB carburettors.

RESULT The four numbers you actually adjust on a diaphragm carburettor: HIGH NEEDLE opening, LOW NEEDLE opening, POP-OFF pressure and EXHAUST LENGTH. The needles come both as a fraction of a turn and as turns and minutes, the two ways they are spoken. Plus air density and density altitude. And two fine tunings, one per needle, to match the recommendation to your engine and how it is prepared.

CONDITIONS The weather, two ways: from the nearest public station, with its distance and the time of the reading, or typed in by hand. It works just the same with no signal.

ENGINE Engine type, Junior exhaust restrictor, carburettor, oil mix and track type. The restrictor list includes 22.7 mm, the current X30 Junior specification since the 2021 update and still in the 2024 and 2025 regulations; 22, 26, 29 and 31 mm are kept for engines still on the previous scheme.

LOGBOOK Saves every session with its conditions and its carburation, and then you write down what you actually fitted and how it went: lean, good or rich, separately for the low needle and the high one. Laps, best lap and max RPM too.

Everything stays on your device. The logbook exports to CSV with the difference between what you fitted and what was recommended, session by session, and can be copied to another phone.

TRACKS 112 karting circuits with their altitude and track length. Picking the track sets the altitude — the circuit's, not the town's — and works out the track type. Works with no signal.

SHARE A card with the four numbers, the engine and the conditions, to send to your mechanic. A session's card also carries what you fitted and how it went.

UNITS °C and °F, metres and feet, mb, hPa, mmHg and inHg, BAR and PSI, millimetres and inches.

The values are a guide and a starting point. Every engine, every build and every fuel is different.