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I had 70hp at the wheel. I'm going back later to get the torque. He didn't have the dyno set up for torque yet. Is that good, bad, or average. All i've done to the engine is full yosh exhaust and power commander.
 

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stock for a FI model is around 73. Should be more with the mods. But dyno's differ from one to another.
 

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Jimmie said:
stock for a FI model is around 73. Should be more with the mods. But dyno's differ from one to another.
I have yet to see a sv650 make 73hp stock, just a number the company likes to proclaim, applies to all bikes.
 

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actual HP may be 73. HP at dynos is measured at the wheel, which means that if you have 70 HP at the wheel your actual horsepower is much higher (i cant remember how much percent, or if it varies from vehicle to vehicle). i think an exhaust and power commander could add up to 10% horsepower, so maybe you gained like 7 HP
 

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evilbologna said:
I have yet to see a sv650 make 73hp stock, just a number the company likes to proclaim, applies to all bikes.
73.5hp and 47.1lbs ft of torque. Motorcyclist Magazine measured on a SuperFlow rear wheel dyno. NOT claimed but fact. FYI. ::)
 

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Jimmie said:
73.5hp and 47.1lbs ft of torque. Motorcyclist Magazine measured on a SuperFlow rear wheel dyno. NOT claimed but fact. FYI. ::)
Magazines dont post real numbers. Fact = majority agreed opinion. Of all the dynos posted here and people posting their results, none have reflected magazine numbers, same goes for 1/4 times and whatnot. Magazines are not to be trusted, their facts are claimed facts.
 

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evilbologna said:
Magazines dont post real numbers. Fact = majority agreed opinion. Of all the dynos posted here and people posting their results, none have reflected magazine numbers, same goes for 1/4 times and whatnot. Magazines are not to be trusted, their facts are claimed facts.
 

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If you have the HP curve and know how to use Microsoft Excel (or any other program that can do curve matching) you can make the torque curve. http://auto.howstuffworks.com/question622.htm will show you how.

In the old days they measured torque with a device called a Prony brake and calculated the horsepower. Torque can be measured directly, horsepower always involves some calculation, even with another old way to measure called a pumping dynamometer. The most common machines today measure the rate of acceleration of a rotating mass and convert the results into horsepower. Many older mechanics and engineers (like me for one) feel this is a less precise method than the Prony brake. The Prony brake is much more accurate and repeatable for a given engine, but it has a big disadvantage. It's very hard on the engine being tested.
 

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I was under the impression that any dyno testing is hard on an engine
 

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I don't know how capable your dyno guy is but.... I had a friend who had a twin dyno'd at a HD dealership because it was the same place that installed all his engine mods. However, he knew it wasn't setup right and took it to some one else in our area. The 2nd dyno guy tuned the engine throughout the rev range by tweaking each cylinder seperately. He ended up with 10 more hp and 10 more ft/lb's of torque. If a dyno is done right it should take atleast 1-2 hours.
BH
 

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Robotben311 said:
I don't know how capable your dyno guy is but.... I had a friend who had a twin dyno'd at a HD dealership because it was the same place that installed all his engine mods.  However, he knew it wasn't setup right and took it to some one else in our area.  The 2nd dyno guy tuned the engine throughout the rev range by tweaking each cylinder  seperately.  He ended up with 10 more hp and 10 more ft/lb's of torque.  If a dyno is done right it should take atleast 1-2 hours. 
BH
good point, I've had people bring their bikes in to be dyno'd that has had every dang performance part you can buy, and we get it on the dyno and it's making less HP than a stock bike. Also happened when I was road racing. Kid's would buy every speed part they could find, and get out on the track and get passed by stock machines. You gotta make the speed parts work with each other.
 

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Jimmie said:
good point, I've had people bring their bikes in to be dyno'd that has had every dang performance part you can buy, and we get it on the dyno and it's making less HP than a stock bike. Also happened when I was road racing. Kid's would buy every speed part they could find, and get out on the track and get passed by stock machines. You gotta make the speed parts work with each other.
Exactly right, your much better off to go out and select a few carefully chosen parts that you know will complement each other, then to go out and slap on everything that says it will gain you a horse here and another here. My good mechanic buddy has seen this time and time again, guys go out and do that and cant figure out why there machine is running like crap now.
 

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Robotben311 said:
I don't know how capable your dyno guy is but.... I had a friend who had a twin dyno'd at a HD dealership because it was the same place that installed all his engine mods. However, he knew it wasn't setup right and took it to some one else in our area. The 2nd dyno guy tuned the engine throughout the rev range by tweaking each cylinder seperately. He ended up with 10 more hp and 10 more ft/lb's of torque. If a dyno is done right it should take atleast 1-2 hours.
BH
i agree if you are dyno tuning. i dyno'd the bike to get a baseline. before the season starts i'll do an actual session with race fuel and get the whole curve setup. just like any engine, the true power is in the tuning.
 

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LOL, yep most kids and ******** think that the bigger the pipe is and the louder it is the more power they make! Every dyno is different so if you test it on one dyno...continue using that same dyno when you add parts and want to test it again. On a car you loose about 10-15% as a rule of thumb from the motor to the rear wheels. Automatics tend to loose closer to the 15% mark. My 02 TA was rated at 315 but made 298 at the rear wheels with 2500 miles on it...of course everyone knew the LS1 motors were under rated from the factor to please the corvete guys :D. As far as out bikes go, not every bike is going to be the same either so one bike may be as much as 3-5hp more than the other. Eitehr way 70hp at rear sounds pretty decent.

Which yoshi exhaust do you have, RS-3 or TRS? Did you have the PCIII programmed for your bike or did you use a preset curve? If possible could you make a sound clip of the exhaust? I have been debating between a yosh slip on or full system and a M4. Was it a big difference in sound between stock and the yosh?
 

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Ya, dynos are only good if you base line your bike when it's stock. And you need to stick with one dyno. Comparing dyno results from two different dynos is like comparing a bannana grown in south america to a bannana grown in my backyard! :D


RandyO said:
I was under the impression that any dyno testing is hard on an engine
The bike isn't getting any air thru the radiator so the bike would probably run a bit hotter than usual. But other than that, I can't imagine it's any worse than a trackday. ??? Anybody have any other info regarding this question? I'm just sorta speculating.
 

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My experience is that you will lose HP with any pipe or muffler that is less
restrictive than stock. The exhaust change will make the bike run leaner so the
PC III is necessary to allow remapping of the FI to compensate for the new
exhaust.
If you tune the air fuel ratio for about 14:1 on a dyno and remap for that you can
get a 2-3.5 HP gain with most open exhausts. A local performance shop claims
typical for a SV 650 with M4 full exhaust and retuned PC III is 73-75 HP and
about 47 Ft/Lb. torque.

8)
 
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