Spark Exhaust Bent Tube 30° Ø 76 × 1.5 mm Stainless Steel Universal G9159

Seventy-six millimetres at thirty degrees, in a millimetre and a half of wall. The biggest thing Spark bends, and a part most catalogues stop short of.

Key Features

• Mandrel-formed 30° bend, AISI 304 stainless steel.
• Ø 76 mm outside, 1.5 mm wall thickness.
• The largest diameter in Spark's bend range.
• Matches Spark's 76 mm straight tube, article G9014.
• Spark part number G9159, made in Mantova, Italy.

The Top of the Range

Above this size Spark does not go, and the reason is that motorcycles do not need it. A bend at seventy-six millimetres exists for shells and chambers — the parts of a custom system that hold volume rather than move gas.

If your design calls for a gas path this wide, the design is probably wrong before the parts list is.

A Gentle Curve in a Big Shell

Thirty degrees over a seventy-six millimetre section produces a long, slow sweep. On a bench it looks like almost nothing; on a finished silencer body it is the difference between a case that follows the motorcycle and one that sits across it.

Handling

It is large, it is thin relative to its diameter, and it will take a dent from a dropped spanner that no amount of work will remove. Two hands, a clear bench, and nothing else on the bench.

Cutting the Ends Square

Squareness matters more as diameter grows: half a degree of error over seventy-six millimetres is nearly a millimetre of gap at the far side of the joint. A pipe cutter or a bandsaw with a proper vee support beats an angle grinder here by a wide margin.

Filler and Gap

At 1.5 mm a small root gap is not a problem — there is enough parent metal to bridge it without the edge falling away. That makes this the most forgiving diameter in the range to weld, which is fortunate, because it is also the most expensive to get wrong.

Price Against Risk

Thirty-five euro. Attempting this diameter without mandrel tooling reliably produces a collapsed inner heel and an oval section, usually twice before anyone gives up — and a length of 76 mm straight costs more than the bend does.

Ordering

One bend per article. Spark builds 30°, 45° and 90° at this diameter.