{"product_id":"spark-exhaust-stainless-tube-40mm-500mm","title":"Spark Exhaust Stainless Steel Tube Ø 40 × 1.0 mm 500 mm Universal G9001","description":"\u003cp\u003eForty millimetres is the size most aftermarket link pipes turn out to be. If you are guessing at a diameter for a one-off system on a mid to large machine, this is the one to guess.\u003c\/p\u003e\u003ch2\u003eKey Features\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eStraight exhaust tube, AISI 304 stainless steel.\u003c\/li\u003e\n\u003cli\u003eØ 40 mm outside, 1.0 mm wall thickness.\u003c\/li\u003e\n\u003cli\u003e500 mm long.\u003c\/li\u003e\n\u003cli\u003eThe most commonly used diameter in Spark's straight-tube range.\u003c\/li\u003e\n\u003cli\u003eSpark part number G9001, made in Mantova, Italy.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eWhy This Size Turns Up Everywhere\u003c\/h2\u003e\u003cp\u003eBecause it suits a wide band of engines. Forty millimetres carries the output of a large twin or a middleweight four without slowing the gas down, and it is small enough to route around a shock and a swingarm without fouling.\u003c\/p\u003e\u003cp\u003eIt is also the internal bore of several Spark db killers — the wide Force insert, the wide Moto GP one, the 40 mm Grid-O and the Force Evo and Konix Evo plug. Those parts and this tube are sized for the same class of machine.\u003c\/p\u003e\u003ch2\u003eBending It Yourself\u003c\/h2\u003e\u003cp\u003eForty millimetres in one millimetre wall will bend on a mandrel bender and will kink on a cheap hydraulic one. If you do not have access to a mandrel, buy Spark's ready-made bends — the 30°, 45° and 90° articles exist precisely so a builder without a bender can still make a system.\u003c\/p\u003e\u003cp\u003eSpringback is real: stainless returns four to eight degrees after the bender is released, so a 45° bend needs to be pulled past 50.\u003c\/p\u003e\u003ch2\u003eWall Thinning\u003c\/h2\u003e\u003cp\u003eThe outside of any bend stretches and thins. On a mandrel bend at a sensible radius the loss is small; on a tight bend it can take a third of the wall away. That is the argument for a factory bend on the tight radii and home fabrication on the gentle ones.\u003c\/p\u003e\u003ch2\u003eThe Inside of the Cut\u003c\/h2\u003e\u003cp\u003eDeburr every cut on the inside as well as the outside. At forty millimetres a burr left on the bore sits directly in the gas path, collects carbon and stops a slip joint seating. A round file and half a minute is the whole job, and it is the step most often skipped.\u003c\/p\u003e\u003ch2\u003eOrdering\u003c\/h2\u003e\u003cp\u003e500 mm per article. A full system on a twin typically eats two to three lengths at this diameter once offcuts and mistakes are counted.\u003c\/p\u003e","brand":"Spark Exhaust","offers":[{"title":"Default Title","offer_id":53617860477194,"sku":"G9001","price":587.0,"currency_code":"HNL","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0949\/7831\/0410\/files\/5c0fcb1c3680e_57d9e3a6-dc49-456e-b0ae-1928f2c807cd.png?v=1788362696","url":"https:\/\/inter-pace.com\/en-hn\/products\/spark-exhaust-stainless-tube-40mm-500mm","provider":"Inter-Pace","version":"1.0","type":"link"}