Power Lines

[thirdrock]

Firstly I would like to say that I really enjoy this forum , though I don`t get much time to post things,there is something that needs to be said. Power readings /claims etc .I really would like to know what is thought to be the standard power output (SAE) at the rear wheel.I have read figures like 130 hp and the like .This is really difficult to accept .I remember reading (with initial shock) in a bike mag an output of 119 sae.Our local dealer says the stock (our stock has an empty cat and is about as good as you are gonna get stock)bikes here read 118 -119 sae (std smoothing).I also see that the jardine site shows 119.3 for stock.This of course would be about right considering the estimated powertrain losses(approx 16%).So where do the likes of ,for example ,another exhaust manufacturer get 127 or so as a stock baseline ?? I have even heard it said that are we not perhaps getting bikes with 150 or more at the crank standard (yeah right)and that this explains the higher readings.I think that in the interests of knowing the REAL advantages from whatever mods ,there needs to be more honest (?) or at least more accurate statements of power outputs.Otherwise we are just kidding ourselves.My two cents.

 

[trey]

well, if you trust dyno mappings being what they are, you can check out the output from the dynos Wayne (tuneboy) did on Steve's Bike...That is a measure of power at the rear tire. It just depends if you trust the dyno output.

-trey

 

[trey]

look on page two of the Tuneboy tech geeky list...scroll down to find the message with all the links. You can look over some of the charts made by SteveReds bike.

-trey

 

[MiamiDave]

I have witnessed/known at least 6 Rockets dynoed, all with empty cat's and mild exhausts all running within a few horse of each other 129-132 RWHP. More than likely Standard-but possibly SAE. I would say full cat boxes and stock pipes to be at 125 RWHP.

Modifciations on similar dynos with the "BIG" mods range from 145-150 RWHP SAE. This seems across the boards, and relatively consistent considering different dynos/climates/mods.

To date, no one that I am aware of has dynoed a stock normally aspirated Rocket over 151 RWHP SAE.

 

[thirdrock]

...sooo let me see now.The standard rocket starts with 140 sae at the crank.... through a driveshaft ,and with a cat in the box only manages to lose...only about 11 % of power...bloody amazing ! Sorry..I don`t buy it.Guess it depends on the dynos

 

[Jethro]

I think that in the interests of knowing the REAL advantages from whatever mods ,there needs to be more honest (?) or at least more accurate statements of power outputs.Otherwise we are just kidding ourselves.My two cents.

Well, here you go. I didn't do a dyno when it was stock, but I did one after each mod.
Blue line- TORs stock intake.
Red line- Jardine header, stock intake.
Green line-Jardine header, 3 K&Ns.
If you don't beleive these numbers then your only kidding
yourself. My 2 cents. :wink:




CLICK TO VIEW

 

[thirdrock]

I was hoping for more reasoned debate (dyno charts can vary for many reasons) ...so I will see what we agree on .Fact one : Triumph claim 140 SAE at the crank - true ??? .Fact two : driveshaft bikes suck about 16% or more out of that .MD I refer to your posting "RWHP" mentioning a new bmw and the 16% and the likelyhood that the rocket would have at least that.Do we agree on this ? .Ok now on one hand I am being told that the standard bike only loses 15 hp (10.72% as opposed to the smaller driveline of the bmw ??) driving through a complete drivetrain and with a cat box full (do we agree that a catalytic convertor sucks power to a degree ?),and then conversely with a good exhaust and air filters we gain in the region of 30 hp .Or is triumph really only saying 140 hp to keep the pc brigade happy or something ... don`t think so. Anyway ,hey it`s no big deal , we don`t ride graphs and figures,we ride a history making legend ,and love every minute of it

 

[thirdrock]

..oh yeah...and hey Jethro , for what it`s worth , I actually think that your figures sound pretty well right (though the triple filter increase is a bit of a surprise ).Think about it though...the tors and jardines really do add a cosiderable amount (I`m sure we all agree on that )..I would say they added quite a bit more than the step from a 125 baseline,if 125 was the actual base to begin with.(in other words I`ll bet you started with a 118 -119 region).

 

[Indyrocket3]

Your 15% est. is not a "must" it's a "rule of thumb" because different drivetrains lose different amounts of power (even vehicles that are the "same" --due to manufacturing variances).

 

[thirdrock]

geeez louise ...to that degree ??? Of course there are differences ,even a Cossack Ural wouldn`t have that much variation Consider this : the new 675 loses 16.5% of it`s ponies through it`s chain drive...anyway the real neat part about the rocket is it`s torque and how little it loses of that compared to others .