450 HP Numbers

[zane5219]

I think stock is like 48-49 horse, all you did was put on a pipe, run u4 and jet it properly? Gainnig 7 to 8hp is a nice pick up.

stock is 58 hp @ 9000 rpm, according to the factory specs...

[zane5219]

I think stock is like 48-49 horse, all you did was put on a pipe, run u4 and jet it properly? Gainnig 7 to 8hp is a nice pick up.

stock is 58 hp @ 9000 rpm, according to the factory specs...

[OHVrider]

I had my 03 YZ450F dyno'd twice to jet it and it got 48 both times and both times the guys dong it said that they were seeing about 46-48 on the YZF's. My KTM 525EXC got 46 on one of dyno's and my old 2000 Husky TE610 got 34 stock and 70 after $2,500 in engine mods. Too much power for me, and the guy I sold it too shattered the rear hub practicing for the V2R in sixth. The compression on that beast was around 12.5:1, I think stock was 9.?:1 and at about 240 pounds I could stand on it and it would not budge. Started great with a big hill.

I think most of you guys worrty too much about HP. Spend the money on some Enzo or RG3 suspension and I bet your faster than adding HP.

It took me a long time to learn that lesson, now suspension is first, second and maybe third on the list.

Cheers,

[OHVrider]

I had my 03 YZ450F dyno'd twice to jet it and it got 48 both times and both times the guys dong it said that they were seeing about 46-48 on the YZF's. My KTM 525EXC got 46 on one of dyno's and my old 2000 Husky TE610 got 34 stock and 70 after $2,500 in engine mods. Too much power for me, and the guy I sold it too shattered the rear hub practicing for the V2R in sixth. The compression on that beast was around 12.5:1, I think stock was 9.?:1 and at about 240 pounds I could stand on it and it would not budge. Started great with a big hill.

I think most of you guys worrty too much about HP. Spend the money on some Enzo or RG3 suspension and I bet your faster than adding HP.

It took me a long time to learn that lesson, now suspension is first, second and maybe third on the list.

Cheers,

[grayracer513]

stock is 58 hp @ 9000 rpm, according to the factory specs...

That is crank horsepower, not rear wheel. A good stocker is 47-48.5. Most AM pipes are good for .5-1.5 hp, and U4 can get you another 1-1.5, maybe 2. 51 would be believable.

[zane5219]

what's the diff in power between a 400 and 426 and 450?

[grayracer513]

Roughly 2 for each step. 44, 46, & 48 more or less approximately estimating.

[phat_450f]

damn man who cares its fast and thats all that matter's...

[GENE426]

a aftermarket pipe made all the diff in the world on my yz450-04

i mean it was slow as far as a 450 goes until i put the fmf ti muffler and powerbomb header

huge diff

[FFRacing79]

a aftermarket pipe made all the diff in the world on my yz450-04

i mean it was slow as far as a 450 goes until i put the fmf ti muffler and powerbomb header

huge diff

I wouldn't consider 1 to 1.5 hp difference huge. Tdub

[GENE426]

I wouldn't consider 1 to 1.5 hp difference huge. Tdub

ITS NOT THE HP ITS HOW IT MAKES THE BIKE RUN

ALL THE BIKES POWER IS SMOOTHED OUT AND ALWAYS THERE

YA GET RID OF THE DEAD AREAS AND IT CAN RUN MUCH BETTER

PLUS I THINK ITS LIKE 3 HP JUST TRY IT..............................

??

[grayracer513]

The FMF system is excellent, and it does take the sag/hit thing out of the middle of the curve compared to stock, and flattens the curve out, extending both ends a little, giving much wider, smoother power delivery, but it's still only good for 1 over stock at peak.

The way the big gains that FMF shows on their web site are achieved is by making no effort whatever to optimize the stocker, while the bike is thoroughly rejetted to run the new exhaust.

The better mag "shootouts" try to get the bike running right for both readings.

[GENE426]

The FMF system is excellent, and it does take the sag/hit thing out of the middle of the curve compared to stock, and flattens the curve out, extending both ends a little, giving much wider, smoother power delivery, but it's still only good for 1 over stock at peak.

The way the big gains that FMF shows on their web site are achieved is by making no effort whatever to optimize the stocker, while the bike is thoroughly rejetted to run the new exhaust.

The better mag "shootouts" try to get the bike running right for both readings.

never said how much hp but it did manke a big diff in preformance!

got it cheap too so i have no complaints with no jetting change

Would jetting make a big diff?

[grayracer513]

never said how much hp but it did manke a big diff in preformance!

Sorry,

PLUS I THINK ITS LIKE 3 HP JUST TRY IT................

I guess I misunderstood.

Would jetting make a big diff?

It can, yes, depending on how close to right the stock jetting is for that pipe where you ride.

[GENE426]

Sorry,

I guess I misunderstood.

It can, yes, depending on how close to right the stock jetting is for that pipe where you ride.

well 1.5 -3 whats the diff

i saw the 3hp on fmf web and another guy had said that all i know is the bike runs much better with it new pipe

[YZDAD1]

2003 YZ450F:

High Compression JE Piston

Ported Head

Hot Cams

Jardine Ti System

Tuned Carb

Modified Airbox

This MX bike put out slightly over 53 RWHP, does'nt sound like much ? But, you know what? It was usually the first bike to the first turn and was never passed on a straitaway with a 300+ lb. rider! ?

btw: The complete bike or motor is for sale!

[B86_Racer]

Burned-

Did you ever get the dyno file that I sent you? I sent a 2nd one that wasn't zipped.

[ttr125smms120]

i HEARD that last year tim ferry had a 70 HP 3 speed yz450f, but it could be a lie

[grayracer513]

well 1.5 -3 whats the diff

Roughly 100%

i HEARD that last year tim ferry had a 70 HP 3 speed yz450f, but it could be a lie

Yes, I suppose it could at that.

It was a 3 speed, though.

[ttr125smms120]

Roughly 100%

Yes, I suppose it could at that.

It was a 3 speed, though.

i dont see the problem with a 3 speed for racing. with 70 horsepower i think you could start in 3rd, and keep it there for the race. unless im missing something