I have a full 2 brothers exhaust on my f4i but I hear/read that a lot of people have slip ons, can you guys educate me on the differences please, I know the difference that one is a full and the other isnt but i'm talking performance wise and/or which is better? Do people choose slip ons because they are easier to install? Thanks in advance

 

Well the biggest difference is in the performance. You will get more performance out of a full exhaust than you would a slip-on. I think people choose slip-ons based off a couple things. The first is cost. A full exhaust tends to cost a couple hundred more than a slip-on. Second personal preference. What is the bike going to be used for? For me, I opted for the slip-on since I won't be taking my bike to the track which leads into needs vs wants. Do I need a full exhaust....nope. So based off of that I went for the alternative. Could I have gotten a full, yep. I talked myself out of it though because it wasn't something I needed. I don't think people base the choice off of ease of installation, but you never know.

 

When you do the full exhaust, you really should do the air filter. When you make that many modifications or that much of a change in the way the engine breathes it is proper to get it tuned so it runs well. Do you have to get a tune? No. Will it sound like ****? Maybe. Will it get bad gas mileage? Maybe.

If you do a slip on and the air filter you should still probably get it tuned, it will get more mileage, power, or life out of the engine by making sure you aren't wasting gas, don't have a proper fuel curve or destroying the engine by having it run too lean or rich. You don't have to have it tuned though. After getting a tune you will notice that it pulls smooth slowly through the RPM range (or it should). Tuning gets rid of hiccups at certain RPM ranges and makes the throttle response crisper and smoother. Like the previous poster said, its all on want VS need. Did I need a full system on my Ninja 250? No. and because it didn't run right and I did not check the engine it bent a valve. So if you don't get a tune, keep on on the maintenance, check the valves and just pay attention. Check the plugs for color (White means lean, Black means rich)

But pretty much if you want to get the most out of the system, even if you get a full system for 5 or 6 hundred, you still have the ~200 on the power commander and a bit less than that to tune. It adds up quick to do it right. If you don't need to squeeze every ounce of power out with the least weight, go for it. Maybe you don't have to and you just like making it go faster and have the money. Go for it. Its just all a matter of your situation.

 

Now compared to stock what would be an estimate gain for a full exhaust? Sorry if this was already answered somewhere, I searched but no luck.

 

It probably tells you on the 2bros website. I would geuss 12hp or so. Do the bmc filter and custom tune.

 

your probably looking at 2-4 hp with a slip on. With a full system, its a little more complicated. You have the full system, the air cleaner mod and the tuning that goes along with it to net the full 10hp or so.

As already stated, a slip on is a simple bolt on mod that doesnt require any more modifications or money.

A full system has the additional cost of the system, plus the powercommander, plus the air box.. plus the tuning. All for a few extra hp. to most, its not important enough or a big enough gain to warrant the extra cost.

Plus, if your riding on the street. A full system tends to put the power higher in the rpm range. Not good for street driving when you want power sooner and down lower.

 

dont want to hijack the thread, but after reading this thread i'm thinking about just getting a slip on over a full system... What is the best Slip on for the money? Yoshi Rs-5, Akrapovic, or Leo Vince Sbk? but are there performance gains with slip ons? which one of those listed has the best performance/sound combination and would a power commander be reccomended? i'm also planning on getting the bmc air filter