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My 2010 1090RR has had a full Arrow system fitted. Max power is now 122 at rear wheel. Don't know what is was before. What's the norm, what should I expect? Seems lower than I would have thought.
 

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Can you post the Dyno results... 122 BHP is low.
 

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And, as an extra special bonus, a pipe moves the peak HP up on the RPM curve and shortens its duration, esp on anything having more than 2 cyls
 

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If the dyno runs at a typical 17% loss from crank to wheel HP, that's about 147HP at the crank. At 13% dyno loss, it's about 140HP. Was the factory spec (HP at crank) 144HP? If so, your bike is right in there.
 

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My 2010 1090RR has had a full Arrow system fitted. Max power is now 122 at rear wheel. Don't know what is was before. What's the norm, what should I expect? Seems lower than I would have thought.
Please update your sig to show the bikes you own, will help with getting the correct advise on tech issues.
 

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My 2010 1090RR has had a full Arrow system fitted. Max power is now 122 at rear wheel. Don't know what is was before. What's the norm, what should I expect? Seems lower than I would have thought.
Seems to be on the low side for that motor, but if it's the bruatle 1090rr, they did have 142bhp motors in the earlier ones.
 

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All dynos read differently...... Fast By Ferraci's dyno was infamously "optimistic".

And rear wheel horsepower (torque) is what you measure. To get to crankshaft HP you must do some mathematical assumptions.

Some dynos have software that does that (makes the mathematical conversion to crank HP from rear wheel), some don't.

The question is: Does it make less power than you can use? and does it make smooth power that allows you to ride quickly with confidence? Is the AF ratio good throughout the engine pull from low to max rpm?

The dyno numbers are otherwise meaningless.
 

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Dyno-BHP - RWHP .. bla.. bla...

If a Dyno is set up correctly, it should not "Measure differently" from another Dyno -- Almost all dynos used for automotive testing are not "Braking Dynamometers" but "Rotational Mass Acceleration Dynamometers"

The way they work is really very simple -- They have a set of heavy mechanically linked "Drums" that the driving wheels are forced against and then you measure how fast the driving wheel(s) can accelerate this rotating mass .. It is then very simple to calculate the amount of energy (In kW/HP/BHP etc.) that your vehicle can deliver to its driving wheels. To allow for a larger span of energy levels most of them also have some sort of dynamic braking system. The delivered energy can be measured and calculated very precisely. (You can calibrate for losses in bearings and other components of the dyno itself.)
In reality you can measure the same thing on a flat level road, by timing a run and knowing the total mass of you and the bike, and by having an accelerometer on board, you can even get the "power curve" - an Iphone has a usable accelerometer built in.. Its no precision instrument, but it will give you an idea-- You need to select a gear where the bike and you can handle a full throttle run without wheelspin or lifting the front wheel too much >:) (A dyno test IS safer .. 0:) )

When testing bikes you have only the rather small area of contact patch between rear wheel and the "drum" so in order to ensure that you get no slipping (i.e. wheelspin) you strap down the bike very hard. This introduces a variable amount of rolling resistance, that will absorb some of the "horsepower" from the measurement, this is hard to quantify, and simply means that you will have a not insignificant error in measured "Rear wheel HP"

The dyno will thus measure how much energy your bike can deliver to the drum(s) - Two different dynos WILL produce different results, and you will also see a variation between multiple "runs" on the same dyno, especially if the bike is taken off the dyno and put back on -- I've personally seen differences of up to 8 kW on a 220 kW Hayabusa dragracer - So, small differences of less than 1-3 kW are only "significant" if they are seen on repeated "runs" - These measurements were done with no "Gearbox and drivetrain compensation" - In its nature the "compensation" will increase the difference seen between for example a "Before and After" dyno test on a "tuning job" -- (By adding 15% to the "difference" for example)

What dynos are really best at is getting the best fuelling tuning and the best smooth power to RPM curves, since they translate directly to smoothness of throttle response and thus the handling of the bike.
We all know that "Top end BHP" and torque numbers are only for bragging rights.. If someone comes along and says: My YamaKaSuki puts down 136 Rear wheel BHP so its more powerfull than your Italian POS with only 128 RW BHP -- Well just ignore it .. A lot of "Horsepower hunting" dyno-tuning really ruins the smoothness of power delivery, usually whti the added "benefit" of a louder aftermarket exhaust system.
 

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My 920 with Arrow decat headers but still using original silencers and Microtec Ecu was set up by Chris at X-Bikes and it did 129 at the rear wheel, I cannot find the original graph to post at the moment.
 

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My 2010 1090RR has had a full Arrow system fitted. Max power is now 122 at rear wheel. Don't know what is was before. What's the norm, what should I expect? Seems lower than I would have thought.
Did you use an aftermarket tuner or reflash the ECU?
 

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Putting any vehicle on a dyno is a waste of time EXCEPT FOR TRUE RACE VEHICLES OR THINGS MAKING STUPID HORSEPOWER
When riding/driving your usual range of throttle is 0-10% if that much
Throttle transitions is what makes riding/driving pleasant
You use a data logger that records A/F, MAP and RPM.....TPS doesn't matter
Delta Alpha does, think of it as accelerator pump measurement
All dynos don't read the same.......ever heard of DynoJet Horsepower?

Want to learn about dynos? From someone that builds them and gas analyzers
Go to FactoryPro.Com
It's Mark Salvisberg
He also has a list of bikes and the power they made
Here's a link
 

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If you can get a cheap "Roll" on a dyno at an event or the like, at a cheap price (Some of the tuning firms here have a "portable" Dyno that they set up as a kind of advertizing) it can be an ok check of how your bike is running. You can ignore the "true HP" or "Dynojet HP" figures and just look at the curve, it will show if you have bad "dips" in power and/or torque. Its not completely useless ...
 

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DKDravis;
Ever notice the number on the upper right on DynoJet dyno charts?
It's called "Smoothing" ......They're hiding all the dips and bumps!
So what's the point of using a dyno???????
Go to FactoryPro.Com and read the explanation
Want more info? go to RBRacing-RSR.com he builds ECUs and add ons
for running nitrous amongst other things......his ECUs write their own base maps and you work in DOS or graphically......just drag the fuel curves with the cursor!
Bob at RBRacing has been a friend for 55 years, he holds all the Bonneville records
for blown liter bikes from '85-'03
Bob used to tune on the 91 Freeway in the middle of the night with a laptop fastened to the tank.......until his wife found out
There's NO MV Agusta on this planet that can stay with his Harley Davidson Bagger
to 140 mph .....after that he says it's too aerodynamicaly unstable to go faster
Well it does have a Garrett ball bearing turbo, that makes boost at idle, water/methanol injection, nitrous and a stereo and saddle bags:ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO:
 

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Noel, will any of those people tune your MV?
 

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Mark Salvisberg at FactoryPro more than likely......if he hasn't done your bike before it's free
Bob at RBRacing-RSR will do mine but probably no one else
I don't need them, I have the full Innovate Data Logger System
and a MicroTec 226
I just need a new SSD laptop and to shorten the cables on the data logger it's made for cars
 

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@Knurl:

Yep, I do know of the Dynojet "Smoothing" It is a "tweakable" setting -- You select over how wide an interval of RPM's you do a rolling average - This is always done on ANY Dyno readout, otherwise you would have a jittery sawtooth "curve" -- Dips or bumps shorter than, say 20 . 50 RPM "wide" you can not distinguish when actually riding your bike .. Its just the way measuring instruments work, when you need a readout that is usefull. I do not know the "Smoothing" intervals that you can set on a Dynojet, but setting it high enough to "hide" real world noticable dips or peaks in HP or torque would produce a curve that you would instantly notice as "fake" -- It IS possible to control fuelling and throttle position so precicely that an engine can play a very nice recognizable melody, just check out the Renault F1 team on youtube -- But you are right in some sense .. If you can tweak your fuelling and ignition on the road or track, that will always be better, since it is "Real world testing"

I know a couple of people who spend almost all of their time (spare or not) tweaking hyper-tuned cars on the road, and ALL of them START out on the Dyno .. Then they go out to do road/track testing
One of them runs a 950bhp+ Audi S2 -- running the classic 5-cylinder block -- I think he is at 2,7 litre stroke and bore kit .. And a rather large turbo ..o_O

The fact that some "oldie" on a bike with an engine construction from a combined harvester :cool: can "do the job" not using a dyno probably just means that it takes him a lot more "trial & error" than the modern upstarts with their "fake" dynos ..

I read all the "FactoryPRo" stuff a long time ago, He is ALSO trying to sell something .. just saying ... Does not mean that he is NOT right, its just an area with a lot of "tweaking"

BHP = Brake horsepower -- an OLD measurement tech from the time of Steam Engines, where you would use a calibrated Brake and torque lever system directly on the flywheel of the engine. ALL HP, True HP or BHP measurements are Calculated and Calibrated, and thus subject to some interpretation.
The ONLY "true" way of measuring an engines output by itself is to attach an AC generator directly to the crank output shaft and see how much energy you can produce in KW
A generator/load set will have a well known efficiency from which you can calculate how much the engine can produce
 

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...and most of this is about "My dick is bigger..." ?

Real world riding simply requires smooth throttle and predictable response. :cool:
 
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