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So can i take off the box that connects both pipes? I know it will be loud but will it still run right...i have taken off the tips...92 vn750...Jr.
 

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lol...Alabama WAS such a peacefull place !!..:wow:
 

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So can i take off the box that connects both pipes? I know it will be loud but will it still run right...i have taken off the tips...92 vn750...Jr.
In my opinion no if you're not doing a lot of modifications. The goats belly equalizes the exhaust and creates needed back pressure. My bike has a fabricated system like the added link. It is a little louder,has a deep mellow tone, and runs great. No backfiring, no loss of low end power.
http://www.scootworks.com/shop.cgi/page=partskawexhaust.htm/SID=1328895564.4082
 

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Can I ask what the H-Box is?? Is it a pollution device. I'd really like to take as much of the emission stuff off as I can get away with and still have the bike run properly....

Thanks.
 

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Captive New Yorker....
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AH, ok, thanks, my Goat's belly is already gone......
 

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I'd leave the GB on. Took mine off once for ****s and giggles, and it seemed like it killed a lot of low end power...however, I left the GB on, and took the tips off, and added piping equivalent to aluminum fence post, and it ran fine.
 

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Linkmeister Supreme
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Kawasaki calls the "H" box or "goats belly" the "POWER CHAMBER".
Removing it will cost you some low end torque and power, while allowing more wide open throttle horsepower. Since I don`t ride with a wide open throttle it seems a bad exchange for me.
 

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I agree with Old Hoss. The expansion chamber tunes the exhaust backpressure to improve the low end horsepower. I took mine off to install Vance and Hines cruzers, and there is a mild loss of low end torque. I was never unhappy with the stock exhaust, but my son dumped the bike some time back and the left side exhaust took most of the brunt.

I would put open exhaust tips on after the goat belly to route the exhaust back far enough. Open pipes give a great sound without loss of the goat belly low end boost, and without being obnoxiously loud. If I had to do a change again, that's what I would do.

Anyway, I think the goat belly is a good thing except for the heat being next to the voltage regulator. You can relocate the regulator if you want to keep the goat belly.
Bronson
 

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Can I ask what the H-Box is?? Is it a pollution device. I'd really like to take as much of the emission stuff off as I can get away with and still have the bike run properly....

Thanks.
The "goat's belly" is NOT an emissions device. If it were, I would have removed it. I have removed ALL the emissions crap from my '02 CA model, which is the CA evap system, and the air injection system on all models. This is the only emissions crap on the Vulcan 750.

The "goats belly" is an important part, and should be left in place. Not only will it make a horrible noise (it will NOT sound like a Harley) without it, but it will mess up the exhaust flow, which in turn messes up the intake flow, which will cause the engine to make less power, lean out the air/fuel mixture, and reduce the rpm range that the carbs can be tuned for. Any reduction in backpressure will cause tuning problems.

If you mainly want more noise, then get an aftermarket system, which was designed for the bike. You will need to rejet the carbs, but the aftermarket system is designed to have nearly the same backpressure characteristics as the stock system, but lower over the entire rpm range. You will not be able to achieve this with a cut up stock system.

I had a brand new V&H Cruzers system on my bike, and loved the way it sounded around town. At low rpms, it sounded a lot like a Harley. But a Harley is a larger displacement 45 degree engine, with a long stroke and smaller bore. It always runs at fairly low rpms. The Vulcan is a smaller displacement short stroke large bore engine which runs at high rpms on the highway, and those high rpms totally killed the nice sound it had at low rpms. Since I am mainly a highway rider, that steady drone it made at 5000 rpm became unbearable, and took all the fun out of riding it. I went back to the stock system, and lost a small fortune in the process. But I like the bike again. Expensive lesson learned for me. Stay with the stock exhaust.

I don't recommend the earshave thing either, you are pretty much stuck with K&N pod filters, which are just a little better than no filter at all as far as actual filtering is concerned, and will allow a lot of dirt into the engine that the stock filters would have caught.

The Vulcan 750s stock intake system is IMO way too complicated, and could have been designed much better at the factory. But. It does work. It was properly engineered to work with a stock engine and exhaust system. Change anything, and you mess up everything. Unless you are an engineer, and know what you are doing.

You can remove the CA evap system and the air injection system without hurting anything, they do not directly affect the intake and exhaust systems, and are only there because of the EPA. Had it not been for the EPA, Kawasaki would not have put that garbage on the bike. You can also turn the pilot screws out a little. Kawasaki knew they were turned in too far, but it was necessary, again to satisfy the EPA, not make the bike run right.
 

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romeobravo172
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For the most part---If it aint broke, don't fix it !! If you want it to sound like an over priced, high price maint-machine and have more $s than GOD, Send me a pm, do I have a deal for you. LOL
 

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For the most part---If it aint broke, don't fix it !! If you want it to sound like an over priced, high price maint-machine and have more $s than GOD, Send me a pm, do I have a deal for you. LOL
In other words, if you want a Harley sound, buy a Harley. That is the ONLY way you are going to get it. NO other motorcycle will sound like a Harley, no mater what kind of pipes you put on it.

I don't understand people trying to make their Japanese bike look and sound like a Harley. If you want a Harley, buy one. Used ones are at their lowest prices ever right now.
 
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