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cycle zombie
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25 Posts
Discussion Starter #1
I have stock exhaust on my 99 Vulcan. I don't really care for a loud exhaust but I hate the way the heat shield looks so I wanted to use exhaust wrap to give it a more custom look. My plan is to get the scootworks bypass kit and then wrap it from the beginning of the header to the tail end of the bypass kit and using clamps similar to the stock ones instead of the clamps that come with the bypass kit since they'll be visible. Anybody foresee any problems I might have?

I read somewhere on the forum that re-jetting isn't necessary but I may have to adjust the air/fuel ratio?

Thanks in advance!
 

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Premium Member
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3,026 Posts
I wouldn't do it. The stock exhaust is a very precisely engineered system, and you will cause problems by modifying it. The part you want to remove is a tuned crossover designed to balance backpressure from one side to another. If you remove it, you will lose power, make more noise (only it won't be a deep sound like a Harley, it'll sound like a Toyota Corolla with a rusted out muffler) and you'll unbalance the exhaust, making it impossible to tune the carburetors to work properly over the entire operational rpm range of the engine.

Better to get an aftermarket system. You may find one on eBay for a decent price. You can properly rejet for an aftermarket system, but there is no way to compensate for the wide variances in backpressure you will have in a butchered stock system.
 

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cycle zombie
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Discussion Starter #3
Bummer!

So I would still need to leave the pre-muffler on if I got a set of Cobra slashcut slip-ons wouldn't I? And if the pre-muffler stays that would mean unfortunately so does the heat shield.. Are the pipes that Vance & Hines offer the only other route for this bike?
 

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Again.... It's your bike, do what you want to it, don't let Jerry scare you off. Several folks have "non linked" exhausts and like the sound. True, you will lose some low end power, but not everyone cares about horsepower.

I too like the stock exhaust.... Cause I do like horsepower. You can remove the goats belly ( the chamber that connects both headers) and replace it with a simple H pipe. A few muffler shops might even weld one up for you for a few bucks.

You really only need to rejet if you alter the air intake.
 

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cycle zombie
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25 Posts
Discussion Starter #5
Still the bypass kit isn't recommended? Recommended meaning I want to prevent my engine from going kaput a year from now because I messed with the exhaust..

The reason for getting rid of the pre muffler would be so I can wrap from the headers all the way back to the muffler. An H pipe would still leave a gap that I would have to figure out how to get around with the wrap..
 

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You can wrap an H pipe. Not that hard... but, you don't have to have one. Your bike will not blow up or die. They sell seperate exhausts , my project bike has a pair of Cobra? pipes that are not connected. They are loud, but I really doubt they are doing any damage to anything other than ones ears. The bypass kit is fine...why would they sell one if it was a bad?
 

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cycle zombie
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Discussion Starter #7
True that.. Thanks for all the advice. I decided to go ahead and buy the Vance & Hines Cruzers that kennyw had for sale and will give em a try. I do a lot of highway riding and my hearing is already starting to dwindle at 27 so I'm not sure I'll want them if they're screaming at 5000 rpm. If I don't end up liking em I'll probably try this mod on for size..

Thanks again
 

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When I go on a long ride, more than 50 miles or so, I wear ear plugs. Now being an old retired Army Helicopter pilot, I know my hearing is already shot in the hi-freq range and I'd like to keep what I have left on the lower end.
 

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They sell it to make money. They saw a market for it because they saw people doing it on their own. They don't care about your bike, only your money. Scooterworks is not a mainstream parts place, like Dennis Kirk or Motorcycle Superstore, who would never sell something like that. Those places do sell aftermarket exhausts, and tell you right up front that you will probably need to rejet. An aftermarket exhaust is THE way to go, and it will not use the "goats belly" It will not be as efficient as the stock system, but it is not really noticeable. you will lose 2-3 HP. But unless you live at a very high altitude. you WILL need to rejet. I installed V&H Cruzers on mine, and it was too lean. I went up one size on the main jets and pilot jets, and that was perfect. I live at 1200 feet.


If the noise on the road becomes too much, you can wear earplugs to protect your hearing. But 95% of my riding is on the highway, and I chose to go back to the stock system, including the goats belly.

But again, the stock system is precision engineered, and once you butcher it up, it will not work properly, and will also cause engine damage due to an unstable air/fuel mixture at different rpms. Specifically running too lean is what damages engines.

On the other hand, there are many people here perfectly willing to lose tens of thousands of miles of engine life just to get rid of the stock intake system, which requires use of inferior air filters. These filters have been tested many times, and if a stock filter is a 10, one of these things is about a 2, as far as filtering ability goes.

It's your bike, you will have to decide what is more important, engine longevity, looks, or sound. Fortunately, with a name brand exhaust system, with proper jetting, you don't really have to give up anything except a few HP.
 
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