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Discussion Starter #1
I was just looking at Ivans performance website. Was surprised that the Slip on muffler and intake made more power than the true duals.

 

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That is pretty much very well known that a 2 into1 develops much more torque and power than duels. The reason, you need back pressure. . Now on racing engines that run at very high RPM, then a much more freer exhaust is desired.

I had a slip on on my V star 950. When I put cobra slashdowns on it, it was very noticeable in the loss of torque and power. So I satayed with a 2 into 1 on my 1300
 

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Discussion Starter #3
That is pretty much very well known that a 2 into1 develops much more torque and power than duels. The reason, you need back pressure. . Now on racing engines that run at very high RPM, then a much more freer exhaust is desired.

I had a slip on on my V star 950. When I put cobra slashdowns on it, it was very noticeable in the loss of torque and power. So I satayed with a 2 into 1 on my 1300
Was really what I was hoping to find. Sure is cheaper than a full on exhaust.
 

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That is pretty much very well known that a 2 into1 develops much more torque and power than duels. The reason, you need back pressure. . Now on racing engines that run at very high RPM, then a much more freer exhaust is desired.

I had a slip on on my V star 950. When I put cobra slashdowns on it, it was very noticeable in the loss of torque and power. So I satayed with a 2 into 1 on my 1300
Was really what I was hoping to find. Sure is cheaper than a full on exhaust.
Please be aware that you will not get those numbers at all with just the exhaust. He did that dyno run with his flash. HIGHLY recommend the flash as the first mod. You do not need intake or exhaust to get it.
 

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Discussion Starter #5
Please be aware that you will not get those numbers at all with just the exhaust. He did that dyno run with his flash. HIGHLY recommend the flash as the first mod. You do not need intake or exhaust to get it.
Thanks for the info. I am not really looking into making it a hotrod, by no means. Was just wondering what a slip on could do compared to a full on exhaust.
 

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Thanks for the info. I am not really looking into making it a hotrod, by no means. Was just wondering what a slip on could do compared to a full on exhaust.
Keep in mind most full exhaust systems are for looks only, yep. They are the same diameter and flow as the stock exhaust does. The main restriction in these systems is the muffler.

I had a 950 and added a slip on and it was great. Then I decided to put a Cobra full exhaust on, Speedster slashdowns, the one that have the supposed power port cross over to act like a 2 into 1. Well wow, I lost ton of torque and power with those, they sure did look great. But was was very interesting the pipes were exactly the same diameter as my old factory pipes. The heat shields make the pipes look bigger than they really are. Aftermarket full exhausts are really for show. a stock bike with a good slip on on will out perform any full exhaust systems.

The only exception is the Cobra full 2 into 1 system, but that is basically the same as a stock exhaust with slip on.

If you look at all the charts Ivan has, the biggest HP gains are from the air intake.

Every aftermarket exhaust company will make pretty wild claims on how much power you will get, but hey have 0 proof or any dyno data to back it up.
 

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Agree that 2 into 1 on metric bikes produce more power, but I do like the looks and sound of the Freedom Performance 4" racing dual exhaust on a bike with hard saddle bags like the Strat Deluxe. I didn't notice any seat of the pants loss of performance either. Never had a dyno run either before or after installing them to verify.

Ivan's flash does more than produce higher torque and horsepower results. It evens out the overall operation of the bike. Less upper rpm back pressure, took away the popping on decel and and between shifts once I added the dual exhaust, runs cooler, and not so much lag when off the throttle at low speed and then back on, and more. I did mine 2 seasons ago and happy ever since.
 

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Discussion Starter #8
Agree that 2 into 1 on metric bikes produce more power, but I do like the looks and sound of the Freedom Performance 4" racing dual exhaust on a bike with hard saddle bags like the Strat Deluxe. I didn't notice any seat of the pants loss of performance either. Never had a dyno run either before or after installing them to verify.

Ivan's flash does more than produce higher torque and horsepower results. It evens out the overall operation of the bike. Less upper rpm back pressure, took away the popping on decel and and between shifts once I added the dual exhaust, runs cooler, and not so much lag when off the throttle at low speed and then back on, and more. I did mine 2 seasons ago and happy ever since.
If I do decide to do and Ivans flash. Will wait till winter, don't want my bike being down when the weather is still nice LOL!
 

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Luckily Ivan's shop is only about 2 hrs from me. On the 2014's he can flash the ECU through the connection port without opening it so I was up there, had it done, and back the same day. :grin:
 
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