dhz bikes do 120kmph?

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^^^^^ describe what POWERBAND actually is and where it comes from...

every engine has a powerband and all engines are designed different so the powerband is different...(narrower or longer)
 
im not finished, forgot the main character.


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Well a Honda cub 50 cc 3 speed auto step-thru weighs [ Dry Weight 75 kg (170 lb) ] and can do 80 kph (50 mph) with 3.9 hp ... so if a 140 cc 4 speed manual pit bike can't do that speed then they're pretty gutless ... LOL ...

Honda Super Cub - Wikipedia, the free encyclopedia

cheers cactus, also i was trying to work out the speed for a 140 using the HP calc u posted earlier, basically if the 140 has around 10hp, i got 92mph for a bike/rider combined weight of 160 but i couldnt see anywhere if the weight is in kg or lbs.. any idea?
 
im not finished, forgot the main character.


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hahahaha i dont think you understand everyone is laughing at you not with you... you are just some ****** who has nothing better to do with hes time

everyone knows cactus knows more than anyone else on this site about engines so your flaming the wrong person lol
 
LOL!!! (again)
I'm not laughing at anyone in particular just the whole thread is a pissa :D
 
hahahaha i dont think you understand everyone is laughing at you not with you... you are just some ****** who has nothing better to do with hes time

everyone knows cactus knows more than anyone else on this site about engines so your flaming the wrong person lol


Bruuuvvvvv, have a whinge, i don't care if people laugh at me or with me..as long as there laughing, i cant here them so what you gunna do, fool?

Just because your incompetent doesn't mean u can "flame" at me.

wake up.
 
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Bruuuvvvvv, have a whinge, i don't care if people laugh at me or with me....i cant here them so what you gunna do, fool?

Just because your incompetent doesn't mean u can "flame" at me.

wake up.

wtf are you talking about lol

incompetent??? you dont even know me haha
 
can anyone picture it? A xr250 going 110 km/h and a stock 125 pitty PASSING IT!!! BAHAHAH!!!
 
It's in lbs so you have to convert kgs to lbs ... 1 kg = 2.2 lbs ...

Convert kg to lb - Conversion of Measurement Units

What you'd have to do is take your bike somewhere where you could mess with the sprockets until you achieved the highest possible top speed ... then put the rider and bike weight into a power/speed calculator to see how much the estimated HP is ...

Drag racers use them (Poor mans dyno's) all the time ... You can buy a Moroso power/speed calculator slide rule ...
 
It's in lbs so you have to convert kgs to lbs ... 1 kg = 2.2 lbs ...

Convert kg to lb - Conversion of Measurement Units

What you'd have to do is take your bike somewhere where you could mess with the sprockets until you achieved the highest possible top speed ... then put the rider and bike weight into a power/speed calculator to see how much the estimated HP is ...

Drag racers use them (Poor mans dyno's) all the time ... You can buy a Moroso power/speed calculator slide rule ...

cool, i get it now :)
cheers
 
can anyone picture it? A xr250 going 110 km/h and a stock 125 pitty PASSING IT!!! BAHAHAH!!!

lol dont you mean... can anyone picture an xr250 doin 110km/h... man that would be screaming its tits off

but as for the pitty over taking it.... sorry MV24..... but sadly not true
 
I'm not feelin it either .... I've ridden a 125 with a lumpy cam and it sure as **** didn't go 110

I'm callin defective speedo on the xr ... probably changed the wheel size without adjusting the speedo :D.... that's the story I'd stick to ;)
 
my yx150 all stock except for a 28mm oko, shade more comp and 14/37 gears was flat out keeping up with cars on the highway in a 110 zone. i weight about 90kg's
i recon the closest i got was about 100/105 as there were just leaving me..
 
Hello. i was wondering if anyone that has a dhz 125, 140 or a 160 can get up to 120kmph.. from what my mates have told me.. myself being 60kg said its bull crap that the site say the 140 would do 120kmph. can any please let me know if this is true.. cheers!
Mine does a bee's dick/poofteenth of a shade over 120... but then it isnt really a DHZ, and it isnt really a standard 140...
^^^^^ describe what POWERBAND actually is and where it comes from...

every engine has a powerband and all engines are designed different so the powerband is different...(narrower or longer)
for the uneducated, ''powerband" merely describes the range of revs any particular motor has, between the minimum and maximum revs, that the engine makes it's strongest spread of power... once upon a time, four stroke motorcycle engines had very broad powerbands, ie they made power down low in the revs, through to high in the revs. (however, they *were* once low-revving engines.)
Old school two strokes were generally considered to have narrow powerbands, where the engine started making peak power high in the revs, until it stopped making power even higher in the rev range.

As technology advanced, four strokes became more peaky, with narrower power bands, and two strokes became less peaky, with broader powerbands. Expansion chambers (exhausts) on two strokes were better designed with the aid of computers and flow programs, to better aid the "supercharging" effect Cactus alluded to... and transfer ports had better flow designs, which means the transfer ports flowed better, and earlier in the rev range, broadening the available spread of power...
Powervalves were added to mx bikes in the early 80's to assist in spreading and smoothing the power delivery, basically they smoothed the transition where the gases flowing through the expansion chamber started to re-enter the transfer ports at velocity, by altering the exhaust port height, which altered the time, or rev range, at which the "supercharging" gases coming back into the motor started to take effect.. putting it simpler, pre-powervalve engines were peaky *****es with narrow power bands... powervalve equipped engines were smoother, with broader powerbands... riding the early pre-powervalve bikes was like being spanked on the back of the thighs unexpectedly with a steel ruler... you knew it was coming, but it always hurt anyway... ;)
Modern Four strokes were lightened, cam profiles were changed, carbies that naturally produce power higher in the revs, strokes were shortened, flywheels lightened and their characteristics were altered to mimic the power delivery of a two stroke.. they became fast-revving, high-revving peaky engines, with far greater outright power, but lesser levels of torque, and that torque is made higher up in the revs...
Meaning a narrower powerband...
so over the years, the powerband of the two stroke mx engine, has become smoother and broader... like a four stroke...
the powerband of a four stroke has become narrower and more aggressive... like a two stroke...

if you still dont get it, the "powerband" is simply two words the wrong way round... it means "Band of Power"... but powerband sounds heaps more awesomer than "Range of revs in which your engine is making it's peak power Vs torque spread"....

im not finished, forgot the main character.


2stroke2.gif

^^^ ha ha ha ha hah a
 
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