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Official BTK Forum Pot Stirrer
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I have been looking to upgrade the "sound" of my vulcan 1500 and have discovered that most folks reccommend to install a jet kit along with new pipes. What is the purpose of the jet kit and is it completely necessary. Also, with the increase of air out, does it make sense to have a high flow air filter added to allow more air in? Thanks for your support
 

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Engine needs air, fuel and spark im proper ratios.

Assuming your engine is correctly calibrated for the optimum mix of air and fuel ( it probably isn't, they usually run a little lean, by that I mean the minimum amount of fuel for the air available ).

A less restrictive exhaust and/or air intake would increase the air in the combustion chamber but the amount of fuel would remain the same increasing the leaness of the engine.

Ideally you must increase the fuel with the increase in air, this is where rejetting comes into play, using larger jets increases the fuel delivered and balances out the extra air for more power.
 

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Official BTK Forum Pot Stirrer
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Discussion Starter #3
Thanks Bob,

So basically, the on going cost of the upgrade is reduced fuel mileage. Oh well, who cares if it sounds better and runs better. I'll be needing to feed my baby.
 

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Actually, you may use more fuel, but you get MORE POWER from the fuel you use. You'll notice the the bike just rides better after you put the new pipes on and get it tuned correctly. You're just improving the breathing of the whole system. As far as what a jet "KIT" is, it's less than what it sounds like. For around $70, you'll get a smaller needle, a larger main jet, and some instructions you can get for free at dynojet.com. You can do this mod yourself if you know a little about carbs. You can just buy a smaller needle and the larger main jet. I just bought an 800 Classic, and all I did was remove the idle/air mixture screw plug under the carb (It comes plugged it so you can't change it). I backed it out a few more turns (gives it more fuel at and around idle). Then I removed the jet needle and shimmed it up about 1/16" to get more fuel in (this controls fuel flow in the mid-throttle range). You may also want to look into a higher flowing air filter, such as the K&N. I also found some instructions on how to remove the baffles from my stock exhaust. The bike sounds awesome now, and runs like a top! Let me know if you want any more info.
 
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