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Tue Nov 07, 2006 8:25 am

Mick C wrote:
Wattie wrote:
Mick C wrote:
NortikittyKat wrote:
BladeBoy wrote:
Pontikat wrote:Kelly Will ya Marry Me :wink: I'm a TOP Polisher


Careful Kelly you might bite off more than you can chew.


Yes well... my eyes were always bigger than my belly... :shock:


Don't worry, Ponti's only a little fella


dont wwanna know how you found that out :lol:

could be the cause of your rash?? might be moustache rash...


What happens on the road trip, stays on the road trip...


Nothing like a midnight Game of "Hide the HELMET" eh "DingoMick"

Tue Nov 07, 2006 8:29 am

Pontikat wrote:
Mick C wrote:
Wattie wrote:
Mick C wrote:
NortikittyKat wrote:
BladeBoy wrote:
Pontikat wrote:Kelly Will ya Marry Me :wink: I'm a TOP Polisher


Careful Kelly you might bite off more than you can chew.


Yes well... my eyes were always bigger than my belly... :shock:


Don't worry, Ponti's only a little fella


dont wwanna know how you found that out :lol:

could be the cause of your rash?? might be moustache rash...


What happens on the road trip, stays on the road trip...


Nothing like a midnight Game of "Hide the HELMET" eh "DingoMick"


and you still haven't given me my twenty cents :cry:


just don't show the photos OK?

Tue Nov 07, 2006 11:08 am

Stereo wrote:
I-K wrote:
mitch179 wrote:my old cbr250rr used to kick out something like 42hp (i had it dyno'd lol)

even had 80,000 k's on it!


I rather suspect the dyno operator might've selected "Ego boost" for the correction factor on that run.

Four-cylinder four-stroke 250's kick out between 36 and 39hp on the dyno.


Surely 42hp is not such an out there figure that it cannot be done.....


Well, do the maths... the difference between 39hp and 42hp is 3hp, or ~8% of the lower figure. So, to get the extra 3hp, you need one stock engine to pump that much more fuel/air mixture and to run that much more efficiently that it ends up making 8% more power than another stock engine.

To put that in perspective, fitting a full system to, say, a 600, and tuning the EFI to suit will lift its power from 100hp-and-a-bit to 110hp-and-a-bit, say from 106hp to 115hp; an increase of 9hp, or just over 8%.

See why I'm being skeptical?

Tue Nov 07, 2006 5:46 pm

i dont understand why you cant believe it, a mate of mine had his bike there the same week and his put out 43 (cbr250rr aswell) i cant find the print out right now but im looking for it ......

the claimed power of a cbr250 is 45ps

so its not impossible by any means, and ive seen heaps of 250's putting out around 40 - 45 hp.

like i said i dont care for defending them cause they are a nugget anyways and i have a better bike now.. but i dont want u to be going "OMG LIES MAN!@#!"

Thu Nov 09, 2006 9:56 am

mitch179 wrote:i dont understand why you cant believe it,


Well, read over my previous post again. It's all there in numbers.

a mate of mine had his bike there the same week and his put out 43 (cbr250rr aswell) i cant find the print out right now but im looking for it ......


Well, there you go. We now have two BabyBlades making more power than expected on the same dyno. More evidence that the dyno in question reads high.

the claimed power of a cbr250 is 45ps


At the crank. Knock the expected ~15% drivetrain power loss off that (which is 6.75hp), and you have 38.25hp at the rear wheel, which is what BabyBlades record on a stringent dyno.

so its not impossible by any means, and ive seen heaps of 250's putting out around 40 - 45 hp.


All on that one dyno?
If the operator is applying correction factors to extrapolate the rear-wheel reading back to the crank (which he shouldn't be), that would explain the high readings.

like i said i dont care for defending them cause they are a nugget anyways and i have a better bike now.. but i dont want u to be going "OMG LIES MAN!@#!"


Again, read back over everything I've said... who, except the dyno, am I accusing of being wrong?

Thu Nov 09, 2006 1:03 pm

mitch179 wrote:my old cbr250rr used to kick out something like 42hp (i had it dyno'd lol)

even had 80,000 k's on it!


My peewee 50 kicks out over 200hp on the dyno :roll:

Thu Nov 09, 2006 6:09 pm

ive seen read outs from different dyno's giving similar figures ... i could probably find them if you really want me to ?

whatever tho, you are seriously a typical know it all.

Thu Nov 09, 2006 6:43 pm

mitch179 wrote:ive seen read outs from different dyno's giving similar figures ... i could probably find them if you really want me to ?

whatever tho, you are seriously a typical know it all.


:lol: He's our favourite pedant !!! But he is pretty bike-savvy...and loves a stouch ..... :lol:

8)

Thu Nov 09, 2006 7:20 pm

mitch179 wrote:ive seen read outs from different dyno's giving similar figures ... i could probably find them if you really want me to ?

whatever tho, you are seriously a typical know it all.


I'm with you mate. I also had a cbr250rr (full race system). Although I never got around to chucking in on a dyno, it felt shitloads faster than any other 250 I've ridden.

Thu Nov 09, 2006 11:18 pm

ross79 wrote:I also had a cbr250rr (full race system). Although I never got around to chucking in on a dyno, it felt shitloads faster than any other 250 I've ridden.


For that statement to carry any weight, you'll need to tell us what those other 250's were.

Thu Nov 09, 2006 11:25 pm

mitch179 wrote:ive seen read outs from different dyno's giving similar figures ... i could probably find them if you really want me to ?


You could, but, once again, without knowing the correction factor applied to the dyno run, the peak power figure is largely meaningless.

whatever tho, you are seriously a typical know it all.


Well, one thing I don't know is how a bike which claims 45hp at the crank can lay down 42hp on a dyno without that second number being treated with suspicion.

Fri Nov 10, 2006 6:29 am

sorry honey all i can here is blah blah blah blah.

Fri Nov 10, 2006 8:59 am

ok, dont flame me please :oops:

but i been thinkin...
if a zx12 can pump out 200hp on a dyno, (not attaking the 12 owner 8) )
if you divide, 200 by 1200cc
and multiply that figure by 250cc
you get about 42hp.

meaning a scaled down 1200 can get 42hp at the wheel.

why cant a cbr do the same??
with a few little mods, and remembering a cbr is reving to 18,000rpm
(imaging what a zx12 would be pumping out if it could rev to that!! :shock: )

anyways, thats my numbers... carry on..

Fri Nov 10, 2006 10:07 am

its only a 4hph power increase from the standard bike... I dont see any reason at all why this isnt probably with minor modifications to the bike....

Fri Nov 10, 2006 11:19 am

The mighty 636 a few years ago when they had the dyno in the main street of Cowes for the GP.

Stock jetting with a Yoshi bolt on.
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