{"product_id":"spark-exhaust-bent-tube-45-degrees-35mm","title":"Spark Exhaust Bent Tube 45° Ø 35 × 1.0 mm Stainless Steel Universal G9130","description":"\u003cp\u003eThirty-five millimetres at forty-five degrees. The working angle in the diameter Spark's small-twin silencers are built around.\u003c\/p\u003e\u003ch2\u003eKey Features\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eMandrel-formed 45° bend, AISI 304 stainless steel.\u003c\/li\u003e\n\u003cli\u003eØ 35 mm outside, 1.0 mm wall thickness.\u003c\/li\u003e\n\u003cli\u003eStraight tangents at both ends.\u003c\/li\u003e\n\u003cli\u003eMatches Spark's 35 mm straight tube, article G9011.\u003c\/li\u003e\n\u003cli\u003eSpark part number G9130, made in Mantova, Italy.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eGetting to the Silencer Position\u003c\/h2\u003e\u003cp\u003eOn a 300 to 500 cc machine the silencer usually sits high and outboard, and the header leaves the cylinder low and central. Forty-five degrees is the angle that climbs and steps across at the same time.\u003c\/p\u003e\u003cp\u003eOne of these off the header, a straight, and a second one into the silencer covers a great many small sports bikes without anything else being needed.\u003c\/p\u003e\u003ch2\u003eTwo Forty-Fives Against One Ninety\u003c\/h2\u003e\u003cp\u003eThey are not equivalent. A right angle at a given radius disturbs the gas once, hard; two forty-fives with a straight between disturb it twice, gently, and let it settle in between.\u003c\/p\u003e\u003cp\u003eAt part throttle the pair usually wins. At full throttle the difference is small. What decides it in practice is space, and the pair is more adjustable.\u003c\/p\u003e\u003ch2\u003eWhat Runs at This Diameter\u003c\/h2\u003e\u003cp\u003eThirty-five is the internal bore of Spark's Force db killer for the Yamaha R3 and Kawasaki Ninja 400, and of its Moto GP inserts. A bend in this size is almost always part of a small-twin build.\u003c\/p\u003e\u003ch2\u003eMarking a Curved Cut\u003c\/h2\u003e\u003cp\u003eWrap a strip of paper round the tube, align the overlapping edges, mark along it. That gives a square line on a curve, which a rule and a marker will not. Freehand marking is why joints arrive with a gap on one side.\u003c\/p\u003e\u003ch2\u003eSupport Near the Bend\u003c\/h2\u003e\u003cp\u003eThe weld at a tangent is a stress concentration and a bend is where a system flexes. Put a mount within a hand's width of any bend that carries weight, and make at least one mount in the run rubber-isolated.\u003c\/p\u003e\u003ch2\u003eWall Thinning on the Heel\u003c\/h2\u003e\u003cp\u003eThe outside of every bend stretches as it forms, and loses wall thickness doing it. On a mandrel-formed piece at a sensible radius the loss is around a tenth; on a badly made bend it can be a third. The outer heel is also where the gas scours hardest, so that is where a system fails first.\u003c\/p\u003e\u003ch2\u003eOrdering\u003c\/h2\u003e\u003cp\u003eOne bend per article. Available in 30°, 45° and 90° at this diameter.\u003c\/p\u003e","brand":"Spark Exhaust","offers":[{"title":"Default Title","offer_id":53618173247754,"sku":"G9130","price":35.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0949\/7831\/0410\/files\/6087d234e1b71_e2a9be99-5c52-47b8-8d98-eff805181bad.png?v=1788347957","url":"https:\/\/inter-pace.com\/en-sv\/products\/spark-exhaust-bent-tube-45-degrees-35mm","provider":"Inter-Pace","version":"1.0","type":"link"}