Approximate HP increase between stock and full aftermarket exhaust?

[dadofthree]

That's what my problem was!

I've heard claims that an air shifter will allow one to knock off .1-.3 in the 1/4mi on a stock wheelbase bike. I did most of my passes foot shifting but did a comparison at the track with one. I made 2 passes with and then 2 passes without. Did this for 8 passes and saw no gain what so ever in ET or mph. Btw, I was clutch less shifting. All 8 passes were within .07 from best to worst. Air shifter passes were not grouped atone end or the other. I will admit that I had less to pay attention to! I like them...

I'm not a drag racer , but curiosity got the best of me on the '06 and on my first run I couldn't get my foot up to shift into second

Back in the day we would reach down with the left hand and shift, but I can't reach the shifter on the Busa

 

[Birdoprey]

No kidding! Took lots of passes to get the hang of it. Takes more effort nowadays due to the extra "padding" in the ol midsection...

 

[dadofthree]

I know what you mean. No padding required to play Santa

 

[Busashot]

I have seen 1.5-2mph gain by dropping 22-23lbs. Just said "in general" and figured that was close enough for a game of hand grenades
I may not know what I'm talking about though...???
I can barely stay on the bike while going down the track

I hear ya. What's the disclaimer say......"Results may not be typical"?

And as far an air shifter, unless you absolutely suck at drag racing then yea don't expect much from one except for perhaps consistency. I have one and I love it.

 

[Stripes]

I know this may sound like a lame question but you need to understand I don't have access to dynos in my area but here goes. How much rwhp does a stock Gen II have? I am getting confused by all the things I see around. I see guys saying its about 166rwhp, somewhere else I saw 177 rwhp, some place else I saw 179 rwhp. Am confused, which is it? What should the rwhp be. lease:

 

[crusty369]

Depends on the bike, to be honest. Big variance depending on how it's built at the factory. That being said.....
ECU Editor, Brocks AlienHead, and a BMC Race filter:
197 HP, 114 TQ on mine, tuned by Johnny Cheese.
Prior to him tweaking with ECU Editor, stock map, mine showed 191 HP, 106 TQ.
In his experience, 3rd GENII to crack the 190 mark on the stock map, aftermarket pipe, and filter.
Luck of the draw....

 

[Travis England]

I went from two brother slip on exhaust to brocks street meg and picked up 12 hp but i also lost 30 lbs worth almist another 10 hp.....on a stock bike 3.3 lbs of weight loss is worth 1 hp

 

[Bubba Zanetti]

My '06 picked up 14RWHP from a full Yoshi 4-2-1 and a K&N Air Filter. Believe it or not the Air Filter on it's own gave 5 of those ponies as we Dyno'd between changes.

And no the old filter wasn't blocked up

 

[Busashot]

My '06 picked up 14RWHP from a full Yoshi 4-2-1 and a K&N Air Filter. Believe it or not the Air Filter on it's own gave 5 of those ponies as we Dyno'd between changes.

And no the old filter wasn't blocked up

Wow. I have seen as much as 5hp with Airbox mod and BMC Race filter. With most exhaust yea I can believe 14hp from exhaust, airbox mod and filter but just air filter alone seems a bit high IMHO

 

[Bubba Zanetti]

Wow. I have seen as much as 5hp with Airbox mod and BMC Race filter. With most exhaust yea I can believe 14hp from exhaust, airbox mod and filter but just air filter alone seems a bit high IMHO

Honest officer

Air box mod was done prior to the K&N so maybe that had more of an effect after the change.

 

[Lamb busa]

151 before full Brocks and air box mod...162.5 after. sea level '05

 

[jazz234]

it would depend on the exhaust you decide on. either way you would want to get it tuned and do the airbox mod and get rid of the pair valve. if you get a brock exhaust and get a powercommander you can get the map from him. if you get it tuned you can do the ecu editor instead of the pc. its better i think. I got the alien head myself. i would bet somewhere between 5 and 10 with a tune or map from brock. plus you drop a good amount of weight so that helps all by itself. just doing the exhaust without tuning i think is conter productive. jmo

 

[Mythos]

The other thing you gain with a full system is a drop in overall weight which means less hp needed to accelerate the bike.

...not to mention, the bike will feel better cornering. I always felt my Gen2 handled very well even with stock exhaust but dropping the extra weight alone is enough reason to go with a full system. I think Brocks is going to be lightest. Akra might be close. Now you look at lightweight parts and figure $/oz what they cost. A full system is a bargain from a weigh reduction standpoint.