Spark Exhaust Grid-O Silencer with Heat Shield Yamaha R9 (2025-2026) G00SI42T

The loudest thing Spark will sell you for an R9. The Grid-O is the muffler that runs on Moto2 and Superbike World Championship grids, where nobody measures decibels, and this is that silencer supplied as a group with its heat shield for Spark's Yamaha R9 collectors.

Key Features

• Grid-O titanium silencer, supplied complete with its heat shield.
• The design Spark runs in Moto2 and Superbike, in series with no noise ceiling.
• Visible TIG weld seams — Spark leaves the welding on show rather than polishing it out.
• Full titanium construction.
• Mounts to Spark's R9 collectors GYA8801 and GYA8802.
• Made by Spark in Mantova, Italy.

Build Quality & Materials

Grid-O is the least compromised silencer in Spark's range because it was never asked to compromise. Where the Force Evo trades some flow for a lower reading and the Konix Evo is sized for European circuit limits, the Grid-O exists for grids that do not impose any. Titanium throughout, hand-welded, with the seams left visible — on a case rolled and welded by hand, the seam is the evidence of the work.

The heat shield in this group is the reason the part number ends in a group code rather than a bare silencer number. Fit a race silencer without one and the first casualty is a boot.

Performance & Sound

This is the option to choose when there is no decibel limit to respect and every reason to reduce restriction. Spark publishes no measured figure for the Grid-O on the R9 specifically; on other platforms where it does publish one, the Grid-O consistently sits at the top of the range. Treat it as a track-day-and-race-only proposition and check your circuit's noise policy before you commit — many European circuits will turn a Grid-O away.

Fitment & Compatibility

Fits Spark's R9 collectors GYA8801 (Supersport chassis) and GYA8802 (standard chassis). It will not fit the standard Yamaha exhaust — the inlet is sized for Spark pipework. If your circuit enforces a limit, look at G00SI44T instead: the Force Evo in a 400 mm case, built specifically to bring the number down.

Road Approval

None, and this one is not marginal. The Grid-O is a competition silencer, it carries no EC approval, and it is loud enough that fitting it to a road bike would be obvious to anyone standing nearby.

Specifications

• Part number: G00SI42T
• Type: Silencer group with heat shield
• Design: Grid-O
• Material: Titanium, visible TIG welds
• Heat shield: included
• Fits: Spark R9 collectors GYA8801 / GYA8802
• Fitment: Yamaha R9 (2025-2026)
• Road approval: None — track use only
• Manufacturer: Spark Exhaust Technology, Mantova, Italy