Jet Mikuni Main #150 LGE Round (4/Pkt)

Genuine Mikuni main jets in the large round-head style, supplied as a pack of four in size #150. Main jets meter fuel flow at larger throttle openings, so the size fitted has a direct effect on how a carburettored engine runs through the mid-range and at full throttle.

Suited to riders and workshops re-jetting a Mikuni carburettor after an intake, exhaust or altitude change, or simply replacing worn or damaged jets during a rebuild. Buying a four-pack means multi-cylinder carburettor banks can be jetted as a matched set, with spares on hand for further tuning.

Check the jet style and size your carburettor requires before ordering — Mikuni uses several different main jet head types that are not interchangeable.

• Genuine Mikuni replacement main jet
• Jet size #150
• Large round head style
• Supplied in a pack of four
• Suits re-jetting after intake, exhaust or altitude changes
• Allows a multi-cylinder carburettor bank to be jetted as a matched set

• 4 x Mikuni #150 large round main jets

Confirm the head style and thread of your existing main jet before fitting — Mikuni large round jets are not interchangeable with hex or small round types.
Remove the float bowl on a cool engine with the fuel tap turned off, and drain residual fuel before unscrewing the jet.
Use a correctly fitting jet driver or flat-blade tool that fills the slot; screwdrivers that are too small will round out the soft brass head.
Tighten by hand only, snug against the seat — over-tightening can distort the jet or damage the emulsion tube thread.
Clean jets with carburettor cleaner and low-pressure compressed air only. Never pass wire, drill bits or picks through the orifice, as this permanently alters the calibrated flow and makes the marked size meaningless.
Inspect the sealing face and threads for damage each time the carburettor is opened, and replace any jet that is scored, discoloured or has a distorted head.
On multi-cylinder carburettor banks, fit the same jet size across all bodies unless a tuning specification says otherwise.
Re-check the jetting whenever intake, exhaust, fuel or operating altitude changes, and verify the result by reading the spark plugs after a controlled run.
Store spare jets in a labelled container away from moisture and swarf so the stamped size stays legible.