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ktm125sx how fast can a ktm 125 sx 2013 go stock and with mods

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hi, how fast do you think a ktm 125 sx 2013 can go in stock condition and with some mods

Edited by Johnno Callea

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Stock probably about 75 mph, change the gearing for ~$50 and with a long flat straight you could maybe do 110 mph but it would take a long time to get there.

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2 hours ago, Johnno Callea said:

hi, how fast do you think a ktm 125 sx 2013 can go in stock condition and with some mods

Really? Why ? My guess is 134 mph

 

Joe

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Mod are irrelevant unless rpm can be increased. Top speed with stock gearing is a little over 70mph. I know i had a 13 125sx and i did a top speed check on GPS. The mathematical calculated top speed at 12000rpm in 6th gear is 73mph. 

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I have a 2000 125 EXC. The only engine mod is slightly reduced compression to be able to run on regular pump fuel. Not a typical performance mod. Top speed with a 45t sprocket and a street tire on back is about 87mph but it can vary. It will do 80mph at any time unless there is a significant hill. Weather and road surface (ie; gravel) are significant factors in reducing the speed back to 80mph. RPM is screaming, even with the 45t sprocket. Wind resistance gets plenty heavy at these speeds and I doubt I could break 100mph even with sprocketing without doing some streamlining. Powerband kicks in at about 60mph and I have driven many miles at 60-70mph. engine is buzzing pretty good. pipes will crack. I don't think she would last too long at over 80mph.

My 2004 Husaberg 450 would do 95mph and my 1986 XT600 would do 111mph for comparisons.

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Why is everybody fascinated with how fast their bike can go. It's not how fast you go but how you ride it, IMO just saying. I always tell people it's faster than you need to be going on a dirtbike

Little Jeff

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On ‎11‎/‎21‎/‎2017 at 8:01 PM, Little Jeff said:

Why is everybody fascinated with how fast their bike can go. It's not how fast you go but how you ride it, IMO just saying. I always tell people it's faster than you need to be going on a dirtbike

Little Jeff

Just kids usually want to know this and ask on here ALL the time Jeff :smirk::excuseme:

 

Joe

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Terminal velocity is an interesting subject Jimmy. Basically your motorcycle would accelerate at  g = -9.81 m/s^2. This means the speed is the square of acceleration, given the initial acceleration of 9.81 m/s, until stasis is reached as a function of aerodynamic resistance. Given that the c.d. of most bikes is around .55 or so (very dirty) with sufficient altitude when initially pushed out of a plane, your sx could near 200mph. Definitely film it when you push it out of the plane.

 

 

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Terminal velocity is an interesting subject Jimmy. Basically your motorcycle would accelerate at  g = -9.81 m/s^2. This means the speed is the square of acceleration, given the initial acceleration of 9.81 m/s, until stasis is reached as a function of aerodynamic resistance. Given that the c.d. of most bikes is around .55 or so (very dirty) with sufficient altitude when initially pushed out of a plane, your sx could near 200mph. Definitely film it when you push it out of the plane.   

 

 

We could all chip in for Felix Baumgartner to ride it. Then your 125 could hit in excess of 800 mph and finish in a fireball.

 

It is comical that these kids post these questions. I'm guessing they're the same ones still trying to remember the clutch is on the right, brake on the left... Wait a minute, or is the clutch on the left??

 

 

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We could all chip in for Felix Baumgartner to ride it. Then your 125 could hit in excess of 800 mph and finish in a fireball.  
It is comical that these kids post these questions. I'm guessing they're the same ones still trying to remember the clutch is on the right, brake on the left... Wait a minute, or is the clutch on the left??
 
 

clutch lever broke off when I let Billy ride it, I just bang the shifter extra hard now
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