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kx125 and kx250/f horsepower

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is there any possible way that a kx125 could have 39 horsepower? is there anyway a kx250 could have 43 horsepower??? please correct me or tell me if i'm wrong

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a stock 2004 kx250 has 56 hp

LOL! That's a good one.

I've heard figures that some of the top factory built 250f's have 43 hp. I would think a 125cc 2 stroke would need a big bore kit to make 39 hp.

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a stock 2004 kx250 has 56 hp

haha..

the new 05-09 yz250 makes 46 on the dyno..

the new 450s arent even at 56 hp.. more like 51-53 hp

stock 125's are around 33 hp with upgrades and a 144 kit 39hp is average

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LOL! That's a good one.

I've heard figures that some of the top factory built 250f's have 43 hp. I would think a 125cc 2 stroke would need a big bore kit to make 39 hp.

RV's 250f made a measurable 45-46hp during the outdoor season..

most modded bikes (close to factory level without the factory parts) can make 43-44 hp, pretty amazing that thats coming out of such a small bore..

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I have always though that most competition (and I don't mean just top level) 2 stroke 125 MX bikes would have had near 40hp. After all the GP 125s are nudging 55hp, so what is difficult about 40hp? 2 stroke tuning is no secret, nor is it expensive like 4 stroke technology.

As for 250 2 strokes, 70hp should be achievable, as the 10 year old Honda NSR500 twin had 140hp. makes 56hp sound feeble.

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At some point what is practical , usable and ridable dictates how far you can push it with a single cylinder. What is also important when comparing hp, is size of your horses? for example my little crfx make 32hp, my klr650 makes 32hp. Ride both and they are nothing the same and no way should be compared, The 32hp in the crfx feels like toy hp. the 32hp in the 650 feels like tractor hp.

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yep, with single cylinders, stroke length, low weight engine parts and what there made of, compression, cams, ect all take a play in how the motor will be used..

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I have always though that most competition (and I don't mean just top level) 2 stroke 125 MX bikes would have had near 40hp. After all the GP 125s are nudging 55hp, so what is difficult about 40hp? 2 stroke tuning is no secret, nor is it expensive like 4 stroke technology.

As for 250 2 strokes, 70hp should be achievable, as the 10 year old Honda NSR500 twin had 140hp. makes 56hp sound feeble.

are thegp 125s twins? is 55 a crank number? id have to say yes to both

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are the gp 125s twins? is 55 a crank number? id have to say yes to both. 250s do make mid 50s...at the crank. the guy got that number from a service manual i bet

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are thegp 125s twins? is 55 a crank number? id have to say yes to both

125 GP bikes are all singles. 55HP at the crankshaft seems resonable on a GP machine, definitely not a MX machine.

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come on guys, motogp 125's are meant to run one race and are tuned by some of the best mechanics in the biz.

Maybe talk to one of those local go cart racers guys, i know they tweak the he## out of those two strokes. But i think they are 250's in most cases. I do know that when they want more power they drop another 250cc engine on the back of their cart...now that is a cool sound seeing those things go down a straightaway with the two engines resonating off of each other.

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At some point what is practical , usable and ridable dictates how far you can push it with a single cylinder. What is also important when comparing hp, is size of your horses? for example my little crfx make 32hp, my klr650 makes 32hp. Ride both and they are nothing the same and no way should be compared, The 32hp in the crfx feels like toy hp. the 32hp in the 650 feels like tractor hp.

have you even even driven a tractor before?

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