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2012 ktm 150sx from a 250f?

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considering getting the 2012 ktm 150sx, Ive been riding a crf250r and i love the torque on it. I was also considering a new efi'd 250f (either kawi or ktm) but ive been reading how these bikes keep on getting more and more unreliable. With my dad working heavy equipment its not a steady job any longer so buying a 7000 dollar bike and soon having it blow up(not saying it will just a possibility) spending some thousands to get it running again is kind of hard to deal with, but if the torque is that much greater than the 150 then we may just go to the 250f. So is there a way to get more power out of the bottom? How does the 150 compare to the 125? I owned a yz125 05 for a while and it was kind of hard staying in ruts cause i couldnt really lug it. I may have gotten better though because now a days on my 250f in ruts i usually shift down right before to get into the higher revs. im also 5'5'' and weigh 123 lbs so the 250sx is kind of out of the question

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The 150 is just a 125 on steroids. It will hang if not beat most 250f's (if you know how to ride it) but the power delivery and torque is completely different then a 250f. After riding a 250f you will be slow on a 150. There is no lugging a 125/150, there is no bottom end. Your either on the pipe or your getting passed. So you can either take the time to re-learn how to ride a small bore 2 stroke or stick with your 250f.

That being said, it sounds like your on a budget so I would get the 150sx and put the time into learning how to ride it fast.

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I concur with Max.... I had both a 150 and a 250f this past year. It is all or nothing with a 150 and being "lazy"/ torqueing around is not an option. If a possible future motor issue is a concern money wise, then a 2 stroke would be cheaper/easier to manage. Good luck with your decision Tony.

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well like i said i ride the 250f in the higher revs anyway, like if i go into a turn/rut i always shift down and have it in the higher revs while going through the turn. Its been over a year since ive ridden a 125 so ill be rusty. Money is an issue though, my dad said if we buy a 250f there will be no mods. if we go 2 stroke we can revalve the suspension. which a revalved suspension makes the biggest difference for me. I also live north of las vegas

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I really like the 150's that I have ridden. THey have alot more bottom than a stock 125. Still not a lugging type bike, but they are good.

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The 150 and the 250F's share pretty much the same horsepower and torque numbers, is just the ol' 4 stroke power band and power pulses vs the 2 stroke and of course the weight differential.

The 150 only has 1.5lb of torque more then the 125 and about 1hp. That difference isn't really enough to feel on the track. The bigger bore is not about the numbers, its about where those numbers happen on the rev curve. Also, the 150 is geared differently then the 125, which is geared poorly stock anyhow.

The 150 won't feel anything like a 4 stroke in terms of power delivery, you'd have to get a 250 2t to get close to a 4 stroke feeling. Even then, its still a 2 stroke and if your not use to a 2 stroke, they are very different.

Yea the new 250F's are falling apart quicker then the older ones, most of that is due to abuse and poor maintenance. If you do preemptive maintenance, you won't have a problem, they are pretty reliable. Nowhere near the reliability of a 2 stroke, but nothing really is.

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I read somewhere that the 150sx is pushing 40hp to the wheel. That is comparable to the 250f. I rode a yz125 not to long ago and I was turning the same lap times on that bike compared to my kx250f. I'm not super slow but no A rider. Good C rider for sure. Maybe slower B. Anyways It didn't take me long to get used to the 125. I've been looking for a 150sx myself and debated on going 125 and having Eric Gorr doing some mods. The weight on a 125 or even 150 would be awesome. They are so light! I bet you would be just as fast on a 150.

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The 150 and the 250F's share pretty much the same horsepower and torque numbers, is just the ol' 4 stroke power band and power pulses vs the 2 stroke and of course the weight differential.

The 150 only has 1.5lb of torque more then the 125 and about 1hp. That difference isn't really enough to feel on the track. The bigger bore is not about the numbers, its about where those numbers happen on the rev curve. Also, the 150 is geared differently then the 125, which is geared poorly stock anyhow.

The 150 won't feel anything like a 4 stroke in terms of power delivery, you'd have to get a 250 2t to get close to a 4 stroke feeling. Even then, its still a 2 stroke and if your not use to a 2 stroke, they are very different.

Yea the new 250F's are falling apart quicker then the older ones, most of that is due to abuse and poor maintenance. If you do preemptive maintenance, you won't have a problem, they are pretty reliable. Nowhere near the reliability of a 2 stroke, but nothing really is.

The 150 actually produces about 2.5 hp and 2.1 ft pounds torque more then the 125. Most anyone that has ridden both bikes will tell you there is a noticeable power difference. The 150 peaks out at bout 40 hp which is right on par with most 250f's. There's no replacement for displacement and the 150 has 19.6cc advantage.

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The 150 actually produces about 2.5 hp and 2.1 ft pounds torque more then the 125. Most anyone that has ridden both bikes will tell you there is a noticeable power difference. The 150 peaks out at bout 40 hp which is right on par with most 250f's. There's no replacement for displacement and the 150 has 19.6cc advantage.

Actually the numbers I posted are real-world numbers, off dyno's. There isn't that much of a difference between the 125 and the 150, I believe the major reason why people feel the 150 is better, simply is from the sprockets and the location of the power on the RPM curve. Even MXA's test in 2008 of the 125 and 144 was 1.1lb torque and 2hp difference. Everyone's numbers are all over the place though, so there isn't any reason to bicker about them. 38 vs 40 hp on a bike that weighs 200lb and with a rider that averages 150lb, is not a big difference in my view.

I'm gonna pick up the few missing parts I need to throw my 150 motor back together again and then I'm gonna dump it into my 125 chassis, re-jet it and go ride the living snot out of it so I can really do an A/B comparison. Mind you, my 125 motor is built and the 150 motor I've got is 100% stock, so I'm anxious to feel the difference.

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So you had a 05 yz125

then a crf250

Now your dad with a not so steady job is going to buy you a new $7k bike.....

IMO go get a job! lol

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So you had a 05 yz125

then a crf250

Now your dad with a not so steady job is going to buy you a new $7k bike.....

IMO go get a job! lol

I wish i live in a town where we dont even have a mcdonalds! The only job you can get is in the gas station/restaurant which the restaurant isnt open yet. Theres also so many resumes that they wont even let people put anymore in. The only reason we are getting a new bike is because were selling the crf250, and this year hes worked most the year making 59 an hour, which is 25 dollars an hour more than his normal wage so we have a little extra money.

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Tye, I'm just saying that most everyone I've talked to says the 150 is noticeably more powerful especially midrange. Your right the numbers are all over the place, let me know what you think after you build your 150.

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Tye, I'm just saying that most everyone I've talked to says the 150 is noticeably more powerful especially midrange. Your right the numbers are all over the place, let me know what you think after you build your 150.

I'm excited! Goin' to pick up the last few parts today! :lol:

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any good mods to do to a 150sx? I think ive made up my mind finally and am going to get a 150sx. I plan on getting the suspension revalved first by a local shop(fineline or pro-action). Then getting the intelajet from dicksracing http://www.dicksracing.com/motorcycle_performance/2-stroke_carb_mods Anything other than that would you guys think would be a good mod? I also dont want to lose reliability. Heres some more that dicksracing does. http://www.dicksracing.com/motorcycle_performance/2-stroke_power_mods any other places you would recommend?

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Something to think about is getting the 250 and putting a fly wheel weight and a different ktm 250 xc head on it will tame the power down. Then you could open it up later down the road. Just a thought.

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Im a little small though at 5'5'' and 123 lbs I don't think id be able to handle a 250t

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any good mods to do to a 150sx? I think ive made up my mind finally and am going to get a 150sx. I plan on getting the suspension revalved first by a local shop(fineline or pro-action). Then getting the intelajet from dicksracing http://www.dicksracing.com/motorcycle_performance/2-stroke_carb_mods Anything other than that would you guys think would be a good mod? I also dont want to lose reliability. Heres some more that dicksracing does. http://www.dicksracing.com/motorcycle_performance/2-stroke_power_mods any other places you would recommend?

The 150sx already has an amazing top-end and I'm skeptical that the intelajet would do much if anything? According to MXA the intelajet improves the 250's top-end significantly and that makes sense since the 250 signs-off much sooner compared to the 150. Just saying that you may want to know that it'll help before dropping that much coin. I'm sending my 250sx carb to Dick's next week

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The 150sx already has an amazing top-end and I'm skeptical that the intelajet would do much if anything? According to MXA the intelajet improves the 250's top-end significantly and that makes sense since the 250 signs-off much sooner compared to the 150. Just saying that you may want to know that it'll help before dropping that much coin. I'm sending my 250sx carb to Dick's next week

Wouldn't it make jetting easier though? Or maybe im just completely wrong

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