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just dyno tested my 06 250 and am not to impressed

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so I just got done dyno testing my 06 250 with very mild porting and a stage 2 hotcam and a stock piston and kibblewhite valves and springs running sunoco 110 we got 26 dynojet hp at 5000 feet what is wrong shouldn't it be more than that or is it just me?

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whats wrong with that? it is only a 250 and at higher elevation!! sealevel it may be right around 30

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There should be a correction factor, so elevation isn't relevant.

What did they say other 250f's dyno at on that dyno?

Did you run a slick rear tire?

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I guess I should add that I have not seen any 250f on this dyno I was running a dirt tire and also tried pump gas and vp 110 and I did jet for each and seen the best from sunoco 110 I did see a stock yamaha 450 run 42 on the same dyno I have been thinking of going to a 14 or 14.5 hc piston and a web cam any input

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williamsmotowerx is right when he says what did other bikes do on THAT dyno. Comparing numbers fromn dyno to dyno from place to place is really challenging and can be misleading.

There should be a correction factor, so elevation isn't relevant.

There is a correction factor but elevation is still relevant. Infact corretion factor used wrong can swing numbers greatly. I can make a 400 Supra a 600 hp car by telling the dyno that I am 5000 feet up when sitting in florida. Infact that is a common thing when the Supra club used to roll into town for dyno days sice they like high numbers.

I can also or otherwise "mispalce" the air temp sensor next the to radiator making it think the outside air temp is 110 degrees and throw down another 25whp.

Bottom line, dynos do not lie, people do, and where dynos are concerned here is more bad information than good. If a dyno is used wrong it is just like using anyother instrument wrong. If you WANT a 45hp bike I can make the dyno say that with you watching no problem. Your best be is to compare what other bikes did around the same climate conditions using the same tye of rear tire set up.

Forget what the number says. Compare it to what other bikes do on THAT dyno. If other 250's are doing 35hp you have a problem. Even other brands. Check into it.

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The #s would be better and probably more consistant if you ran a street tire on it. 42 out of a 450 sounds a little on the low side also. Dynos are best using them for before and after comparisons to figure out percentige of gain when tuning and making changes more than the actual hp #s. How the bike feels on the track is what matters most.

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Your are wasting your time testing the bike with a knobby tire on it.

A power increase will cause more wheel spin and even less power according to the dyno with a knobbie.

Many years ago I was sold my first dyno and sales guy promissed the reading wouldn't be much differrent with a knobby the day it was delivered... two hours later we knew this wasn't true anything up to 30o/o power loss throught the Knob's slipping on the drum.

Go buy a cheep road tire or you mite be lucky and find a used one out the back of the local bike shop off a worn out roadie and you mite get closer to the numbers your looking for.

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The #s would be better and probably more consistant if you ran a street tire on it. 42 out of a 450 sounds a little on the low side also. Dynos are best using them for before and after comparisons to figure out percentige of gain when tuning and making changes more than the actual hp #s. How the bike feels on the track is what matters most.

This is so true, ----The dyno is just a test tool, every dyno will read different .

there are so manny different variables, using a dyno for compairson from starting power as a baseline and then doing different builds tunning and many different runs untill you start getting the best gain.

and you work from there.

trying to match numbers to numbers that you may have seen somewhere posted in a magazine or on a web sight is a moot point and should be avoided.

I have an old 150 dynojet, and two of my buddys in town close to me have newer units ( one is a 200 and the other is a 250, one has an eddie current for loading and one has a tuning link for FI work,----( Jerry Hall has an automotive in ground dyno which I want to upgrade to for my shop , ----but the numbers are way way different again )

and you can run one bike on all for units and get very different numbers .

I even see different numbers with the different color 250 make of bikes but they seem to run simular on the racetrack.

so don't get all worked up over nothing

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I use the same wheel on all the bikes i can .Knobbys dont work and soft slicks give inconsistent numbers my wheel has a hard rubber tire that never seems to slip or wear out .i just dynoed bikes here before daytona and they were taken to florida and dynoed with the same tire and produced identical results .i tested an04 crf 250 with a knobby one time it produced around 25 hp with the smooth tire it was @ 32 hp the 06 and newer crfs made around 35 hp i have found it dificult to get beyond a 7 hp increase from a newer honda 250 and still keep a good power curve .

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so today I was running my bike again and we noticed that at around 9000 to 11500 the fuel curve gets way richer it drops down to about an 11.2 afr just out of curiosity another guy told me to unwrap my head pipe and it got about .5 afr leaner throught the whole curve any ideas why it is gouing so rich at 9000

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When you can read the power....jet for power, not AF!

I bet the reading is scewed somehow.

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I have seen this guy make power on alot of machines but my bike is the only one he hasn't been able to make over all hp in at least an hour i really think somthing is wrong

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so today I was running my bike again and we noticed that at around 9000 to 11500 the fuel curve gets way richer it drops down to about an 11.2 afr just out of curiosity another guy told me to unwrap my head pipe and it got about .5 afr leaner throught the whole curve any ideas why it is gouing so rich at 9000

you just have to play with jetting , do not get fooled into thinking you should have a certin afr number that some chart or book shows,

you just jet and see where your bike runs its best at.

trying to go for a certin afr that you think it should have will screw you up again .

I do not wrap headers unless I am at the drags behind the Glamis store in the winter.

I don't know what build you are doing and or what type dicipline of riding you do with your bike , but at the altitude you sure do not want it rich at all

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mine has kibble white valves and stock cam hot rod crank wiesco piston and white brothers pipe and it is around the 35 hp mark so i would imagine you should get more hp than that

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