Why is a stock kx250 so much more powerful than our klx250s or even 350s?
#11
If you look at the 2 stroke you will see that the "TUNED" pipe is resonating the back pressure and forcing all of the unburned fuel back into the cylinder (supercharging) the cylinder. the length of the pipe has alot to do with the rpm that the motor makes power in. typically the shorter the pipe the higher the power band. AND the fatter the pipe the wider the power band (to an extent).
#12
The picture shows the entire tuned pipe, not just a header. the 2 stroke needs a pipe shaped like this to create the harmonic resonance to force the unburned fuel into the cylinder. the reason for this is the location of the ports and the port timing (there are no valves). the animated diagram posted is awesome. I wish i had seen something like this 40 years ago to better explain it to me.
#13
It's not too late....people switch bikes all the time. There are many people that have a 2 stroke KTM that got more engine under them than they wanted, and would love to swap for a more sedate 4-stroke. Be sure and provide full disclosure about what you've put yours through, though.
#14
It's not too late....people switch bikes all the time. There are many people that have a 2 stroke KTM that got more engine under them than they wanted, and would love to swap for a more sedate 4-stroke. Be sure and provide full disclosure about what you've put yours through, though.
#15
Hi jhoffy, was this 2011 KX 250 a two stroke or four stroke? I don't know of any KX 250 two stroke made in 2011.
#16
This bike is stuck with me for life As soon as I tell someone that I blew up the top end they probably won't want anything to do with it. I might get $2k for it at best. If I could find the right price for a ktm though, I might consider. They are so much pricier than the klxs though.
If it doesn't float your boat, advertise for a swap with someone with a KTM...you just never know when someone really just wants a small 4-stroke dual sport, and would swap you even.
#17
Do you really think a KLX 350 would make way more than 30 lb/ft of torque? A modern 250 2 stroke MX bike will make over 30 lb/ft and almost 50 hp and be extremely reliable and long lasting at the same time.
Last edited by zomby woof; 10-15-2011 at 02:56 PM.
#18
My point was that (totally aside from the two-stroke/four-stroke differences), dedicated MX bikes are designed to produce much more power than our KLX trail/dual sport bikes, even with the same engine type.
But back to jhoffy's original question...yeah, it's the two stroke part of the equation that made the KX250 power 'overwhelming' and 'insane' compared to his KLX350. That's the 30+ lb/ft and nearly 50 hp at work!
Last edited by Lutz; 10-15-2011 at 03:38 PM.
#20
Yeah, those 250F MX bikes are the 'bomb!' Too literally. For pure offroad, I'll take a two stroke every time.