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Hi everyone!
I am putting a 2002 ET4 back on the road for a good friend. It is pretty much in stock condition, other than the TiForce exhaust. Even the jets are original, which must be incorrect. Does anyone know which pilot and main jet sizes would be correct? Also, is there are source for replacement muffler support clamps? This one snapped in two.[/b]
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NO ONE here has rejetted an ET4 to suit an aftermarket exhaust? I am disappointed... Facepalm emoticon
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Why do you think you need to rejet an ET4 after installing an aftermarket exhaust?
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Most performance/aftermarket exhausts flow more exhaust gases than the original mufflers can, so that allows more air to enter through the carburetor, which leans it out (changes the air-to-fuel ratio). The jet sizes usually have to be increased to compensate for the increased air flow entering the engine. The proper air-to-fuel ratio must be maintained to prevent overheating, backfiring, and poor running.
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You will not need to rejet unless you change the intake side. It is not taking in any more air and fuel because you changed the exhaust.
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Then there's the matter of the valves...
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Tierney, I have to disagree with you on that point. Here is a much better explanation than mine of why rejetting is necessary: https://www.cycleworld.com/story/blogs/ask-kevin/why-rejecting-is-necessary-when-exhaust-system-is-changed/
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