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Discussion Starter #1
I have searced all over the Internet with estimated horse power, can't find anything. I have an 05 predator with 560 big bore wiseco 12.5:1, web cams, oversized carb(tuned perfectly) titanium valve springs, timing, chain, and a yosi full exhaust. If anyone know an estimated hp amount that would be great. Also, can I take 450s with this thing, I just got the machine. Thanks
 

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Complete guess from me but here we go 35-40. Now someone can tells how wrong I am
I wouldn't say wrong , maybe generous on your guess. My guess would be lower than yours.
 

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From what I know, they are about 40hp stock. Big bore kit is good for about 5, pipe and cams would be a guess at 4-5 more. So somewhere in the 48-52 range would be my guess.
 

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Discussion Starter #5
They are like 42 to the wheels stock. Which would be closer to 50hp at the flywheel. And I heard all my mods add about 25hp so I was thinking 75hp at the flywheel and also the mechanic in my area said around 80hp at the flywheel
 

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Take it to a dyno. Every big bore kit is different, how it's installed, how it's broken in.
The one thing hat will hurt this in a drag is the crazy weight of the predator, and all the weight is forward, so bad traction out back.
 

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Will have more torque, but still not as fast reving as a 450. Should be able to run with stock and slightly modded 450's. I used to love Preddys, especially the 2005 TLD orange Predator, but yes they are heavy.
 

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25 hp is alot to gain, I woul think 15 would be the most and that would still be a big gain, but I'm no expert. I'd say truthfully its prob 8 to 10 hp gain
 

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Front tires pull off the ground 1st 2nd and 3rd gear. It has power at any rpm, very snappy. I am very happy with the way it runs. And I have read a lot that just a pipe and jetted can get 10 hp. You also have to consider the difference between wheel horse power and block or flywheel horse power. Obviously a lot of people on here do no know the difference
 

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Except the power loss on a machine with a clutch and chain drive is not really a loss if you have your sprockets set right.
 

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A dyno is your best bet to find out the info. your looking for.
 

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Front tires pull off the ground 1st 2nd and 3rd gear. It has power at any rpm, very snappy. I am very happy with the way it runs. And I have read a lot that just a pipe and jetted can get 10 hp. You also have to consider the difference between wheel horse power and block or flywheel horse power. Obviously a lot of people on here do no know the difference
I know the difference in flywheel hp and hp to the rear wheels or to the ground. I've read alot about alot of things that I don't think is possible, for instance muzzy claims there exhaust and programer will give a stock brute force 12-15 hp. But then u hear people saying they put a full muzzy and programer on their brute and they can barley tell a difference in performance. If the exhaust and programer done what it says there would be a very noticible difference with a 15 hp gain. I'm just saying if u gained 25 hp from ur mods that would be a little over half the hp it had before the mods.. Not saying it couldn't be done or that urs isn't what u say it is, just saying that's alot of hp to get from a engine that only makes 50 hp stock. But if ur pleased with the way it performs who cares how many hp it has just ride the hell out of it and enjoy it! That's all tht matters anyway
 

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...I know the difference in flywheel hp and hp to the rear wheels or to the ground. I've read alot about alot of things that I don't think is possible, for instance muzzy claims there exhaust and programer will give a stock brute force 12-15 hp. But then u hear people saying they put a full muzzy and programer on their brute and they can barley tell a difference in performance. If the exhaust and programer done what it says there would be a very noticible difference with a 15 hp gain. I'm just saying if u gained 25 hp from ur mods that would be a little over half the hp it had before the mods.. Not saying it couldn't be done or that urs isn't what u say it is, just saying that's alot of hp to get from a engine that only makes 50 hp stock. But if ur pleased with the way it performs who cares how many hp it has just ride the hell out of it and enjoy it! That's all tht matters anyway
You are correct to question the claims made by many manufacturers of "performance enhancing" devices.

One needs to read the fine print (and read "between the lines" too) as many will use the term "up to..." but not be obvious about it. Generally this means only under ideal circumstances will the claim of "X" be reached. Its extremely rare to find an engine in such a bad state of tune that would actually allow the "up to" claim to be met.

I tune motorcycles and constantly get riders demanding to know why their machine doesn't produce "X" hp as advertised by the maker of their just-installed magical whatever. It's both sad and true that millions of dollars are spent every year on such devices and don't provide the rider with the results "promised" in the ads. IMHO, many of those ads are barely legal just because of the "up to" term.

To the OP's question...I've heard on several occasions that a normally aspirated gas engine (without NO2, heavily restricted intake/exhaust, detuning or such) on a standard atmospheric day could produce approximately 3/4 to 1 hp per cubic inch of displacement.
 
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