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power increase and jetting question
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Posted by: 07250ex

I just bought a hmf sport series and a k&n air filter when i rejet how much of a power gain should i notice with these ? also what should i rejet to if i run airbox lid off k&n with outerwears and a hmf with quiet core ... also what should it be jetted to without the quiet core?

Posted by: dirtdawg

in the performance thread it says 110. i run a 102 with a twinair filter and hmf full but not the quiet core. i putting a k&n in soon w/ outerwears so i'll let you know what i come up with to help you out.

Posted by: hondariderdylan

yea

read the first thread on here
then if it doesnt answer your question, post a thread

but i dont think it gives horsepower #'s
not sure maybe 20-25?

Posted by: 86250rrider

quote:
Originally posted by hondariderdylan
yea

read the first thread on here
then if it doesnt answer your question, post a thread

but i dont think it gives horsepower #'s
not sure maybe 20-25?

maybe 20 TOPS...........these are no firebreathers here ! but still fun

Posted by: hondariderdylan

i figured 25 if he added all the stuff people normally get along with exhuast
jets
filter
rev box maybe
etc.

the motor already puts down 17 horses
not sure

wish i had a dyno in my back yard

Posted by: FlewByU352

quote:
Originally posted by hondariderdylan
i figured 25 if he added all the stuff people normally get along with exhuast
jets
filter
rev box maybe
etc.

the motor already puts down 17 horses
not sure

wish i had a dyno in my back yard

That must take a huge bore to get a 250ex to 25HP. Dont think you realize a stock 400ex puts down 27HP and it would beat any modded 250ex motor. Not trying to put it down just throwing around some facts.

Posted by: 07250ex

quote:
Originally posted by hondariderdylan
i figured 25 if he added all the stuff people normally get along with exhuast
jets
filter
rev box maybe
etc.

the motor already puts down 17 horses
not sure

wish i had a dyno in my back yard

you'd have trouble getting me to believe a 250ex puts out 17 without a dyno ... yes i know the sticky at the top exists also anyone with hmfs is it truely necessary to rejet if ur switching to quiet core or removing the quiet core?

Posted by: hondariderdylan

quote:
Originally posted by 07250ex
you'd have trouble getting me to believe a 250ex puts out 17 without a dyno ... yes i know the sticky at the top exists also anyone with hmfs is it truely necessary to rejet if ur switching to quiet core or removing the quiet core?

true
i was overstating when i said 25, my bad

the sticker on the front of the 250's frame has net HP #'s and its 16.8

look for your self

Posted by: 07250ex

quote:
Originally posted by hondariderdylan
true
i was overstating when i said 25, my bad

the sticker on the front of the 250's frame has net HP #'s and its 16.8

look for your self

wow i honestly never knew that ... you dont happen to know what the 300ex pushes out do you?

Posted by: hondariderdylan

yep, its pretty cool

no but i can find out

i will post up in a minute
hold on

Posted by: hondariderdylan

well heres a shocker:

250EX:16.8 Hp
300EX:17-18Hp

wow
big jump.......

Posted by: 07250ex

quote:
Originally posted by hondariderdylan
well heres a shocker:

250EX:16.8 Hp
300EX:17-18Hp

wow
big jump.......

yeah how do you find all this out i would love to get my hands on a link to a website with such knowledge ... and man im tellin ya if they would cut out this shaft drive **** our 250s would be damn near equal the 300 (even though it pretty much is) with all the weight it would save.

Posted by: hondariderdylan

you just took the words from me
i hate the driveshaft even though you dont ever have to worry about it

thats the 2 things i dont like about it, weight and shaft

oh yea, i just typed in "300ex stock horsepower" on google and the first 2 results said 17-18

Posted by: FlewByU352

17HP on a 250ex might be at the crank. 300ex being 17-18 sounds more like at the wheels. Its a bigger motor and all.

Posted by: hondariderdylan

quote:
Originally posted by FlewByU352
17HP on a 250ex might be at the crank. 300ex being 17-18 sounds more like at the wheels. Its a bigger motor and all.

either way, they arent firebreathers but i expected a bit of a jump besides 1 or 2 hp

crank or back tires