55MM Cylinder Piston Assembly with Spark Plug Pressure Reducing Valve for Husqvarna 385 390 for Jonsered 2186 2188Nikasil

The Husqvarna 385 and 390 and the Jonsered 2186 and 2188 are the same big-bore platform under two badges, which is why one 55 mm top-end kit is listed across all four. If your saw is on that list and the bore has picked up, this is the set that replaces it.

55 mm at the cylinder base

Fifty-five millimetres measured at the cylinder bottom is the number that governs fitment, and it is the only dimension the supplier puts in print. Stroke, gudgeon pin diameter and ring count are all missing — the pin size especially, since that is what decides whether a new piston will sit on your existing rod. The machines named are the Husqvarna 385 and 390 and the Jonsered 2186 and 2188. Nothing outside that list is offered as a fit.

Two things in the source that do not add up

Worth knowing before ordering. The supplier's fourth bullet claims the kit suits the Husqvarna K650 and K700, which are cut-off saws from a different engine family, and that line contradicts both the title and the supplier's own application field. The title's list is the one reproduced above. Materials are given twice and differently as well: iron and aluminium in one place, nichrome in another. Neither conflict has been resolved, so both are set out here as printed rather than smoothed over.

Key features

• 55 mm cylinder: the single published dimension and the basis of every fitment decision.
• Two badges, one kit: Husqvarna 385 and 390, Jonsered 2186 and 2188.
• Pressure reducing valve included: the decompression fitting a big saw needs to pull over by hand.
• Spark plug supplied: ready for the first start once everything is back together.
• 940 g: the shipping weight given for the complete kit.

Specifications

• Cylinder bottom diameter: approx. 55 mm (2.2 in)
• Stated fitment: Husqvarna 385, 390; Jonsered 2186, 2188
• Materials: nichrome in the specification field, iron and aluminium in the feature list — the two disagree
• Weight: approx. 940 g
• Colour: as pictured
• Bore plating: the title runs "2188Nikasil" together; whether that names a bore plating on this cylinder or is a typing slip is never clarified
• Stroke, gudgeon pin diameter and ring count: not published

What's in the box

• 1 x cylinder
• 6 x piston assembly
• 1 x spark plug
• 1 x pressure reducing valve

Working notes for the rebuild

• Assembly follows the saw maker's published sequence, using their figures for every fastener that gets torqued. None of that arrives with the kit.
• Pressure-test the crankcase before the new cylinder goes on. A leaking seal is what took out the last piston and will do the same to this one.
• Two-stroke engines run on petrol premixed with oil. Take the ratio and oil grade from your machine's manual; nothing on this page states one, and none should be inferred.
• An aftermarket kit. The source never calls it genuine, and the Husqvarna and Jonsered names appear to identify the saws only.
• Confirm bore and pin sizes against the parts coming off, and study the photographs, before ordering.

Listed for the four machines named above and no others.

Returns, Refunds and Replacements

Products received faulty, damaged, or not as described are eligible for a return, refund, or replacement in accordance with local consumer laws. We are committed to ensuring all products meet the standards of quality and reliability expected by our customers. Please note that we do not accept returns or provide refunds for change of mind. We encourage you to carefully consider your purchase to ensure it meets your needs and expectations.