KTM 125 or 150?

tempura
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tempura
Which and why?
I have a Japanese 250 smoker and a 4stroke.
Itching for a new lite 2 stroke..lol
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#434
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#434 2/19/2018 1:44am
2/19/2018 1:44am
I'd like some info about the difference between the two bike too! My next bike is probably going to be a tc125/150. I had a 2010 150sx and loved it, but the powerband was short and abrupt. Has somebody ridden the newer generation 125 and 150 back to back?
jemcee
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jemcee 2/19/2018 1:55am
2/19/2018 1:55am
My mate's got a 150 and he's having a love affair with it haha reckons it's the perfect bike.. faster lap times than his 250f! He just came second at a vet race here (Hervey Bay, Sunshine State for those playing at home) and almost every other bike was a 450 or 350..
I'd have one for sure
Motofinne
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Motofinne 2/19/2018 1:59am
2/19/2018 1:59am
Combine the fact that it is a really, really light bike with the HP it makes at stock trim. The 150 is a rocket ship in the right hands.
Jrewing
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Jrewing 2/19/2018 2:08am
2/19/2018 2:08am
Motofinne wrote:
Combine the fact that it is a really, really light bike with the HP it makes at stock trim. The 150 is a rocket ship in...
Combine the fact that it is a really, really light bike with the HP it makes at stock trim. The 150 is a rocket ship in the right hands.
What do they weigh?

The Shop

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tcallahan707
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tcallahan707 2/19/2018 3:09am
2/19/2018 3:09am
Buy either. You can swap pistons and cylinders so you can have both.
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#434
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#434 2/19/2018 3:09am
2/19/2018 3:09am Edited Date/Time 2/19/2018 3:16am
Motofinne wrote:
Combine the fact that it is a really, really light bike with the HP it makes at stock trim. The 150 is a rocket ship in...
Combine the fact that it is a really, really light bike with the HP it makes at stock trim. The 150 is a rocket ship in the right hands.
Jrewing wrote:
What do they weigh?
88 kg (194 lbs) without fuel.

Edit: that's almost 11 kg less than a 250sxf, which is the lightest 250f. Or 20 kg less than a rmz450 for that matter..
Motofinne
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Motofinne 2/19/2018 3:39am
2/19/2018 3:39am Edited Date/Time 2/19/2018 3:41am
Motofinne wrote:
Combine the fact that it is a really, really light bike with the HP it makes at stock trim. The 150 is a rocket ship in...
Combine the fact that it is a really, really light bike with the HP it makes at stock trim. The 150 is a rocket ship in the right hands.
Jrewing wrote:
What do they weigh?
#434 wrote:
88 kg (194 lbs) without fuel. Edit: that's almost 11 kg less than a 250sxf, which is the lightest 250f. Or 20 kg less than a...
88 kg (194 lbs) without fuel.

Edit: that's almost 11 kg less than a 250sxf, which is the lightest 250f. Or 20 kg less than a rmz450 for that matter..
And it makes around 40 hp stock. Like i said, a rocket ship in the right hands. But the same can be said about any other bike haha...
six10
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six10 2/19/2018 7:33am
2/19/2018 7:33am
125 if you are a novice, 150 if you have experience. 150 is a rocketship, that is meant to be pinned. I used to love 250f's for their torque, but once I tried the 150, I switched immediately. I love it.
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Zaugg 2/19/2018 7:40am
2/19/2018 7:40am Edited Date/Time 2/19/2018 7:59am
You can't go wrong with either bike.

I've ridden them back to back and the only difference is power delivery.

125 is very linear. Pulls and pulls. Seems to rev forever.
150 hits hard at the bottom/ middle and then levels off at the top.

If you get either you can buy at kit to turn the 125 into a 150 or vice versa.

In either configuration, they are super fun with plenty of power.

erik_94COBRA
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erik_94COBRA 2/19/2018 7:48am
2/19/2018 7:48am
125 so you can buy 150 kit later if you'd like. Have to buy individual 125 parts.
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brocsdad
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brocsdad 2/19/2018 7:49am
2/19/2018 7:49am Edited Date/Time 2/19/2018 7:50am
If you read the tests most riders preferred to race the 125 because it has a more forgiving powerband. The 150 lacks bottom and hits hard in the midrange and revs to the moon. It is fast but harder to ride. We owned a 125 and my sons friend had the 150 so I have ridden both.

The pre-17 models were the opposite with the 150 making great low and mid but no over-rev.

Good Luck!
nascarnate326 2/19/2018 7:59am
2/19/2018 7:59am
I would go for the 150. Yes it has very little bottom end but if your riding a small 2 stroke its to be expected.

I rode a 2018 SX150 on a sand track in Indiana last fall...loved it.
nobueno
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nobueno 4/3/2021 6:25am
4/3/2021 6:25am
Hey guys, Im looking at getting a 125 or 150?
Im reading conflicting information.
Some say 125 revs, some say 150 rev.
Im just wondering for 2020-2021 which bike has what power characteristics?
Thanks
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Darrin Willis 4/3/2021 6:41am
4/3/2021 6:41am
I have 2hrs on a 21 150. It hits hard and then flattens out. It has enough low end torque to make a great single track bike.I love it so far.
King_George_III 4/3/2021 6:45am
4/3/2021 6:45am
I've had a 2011, 2017 and 2019 150. And my last bike was a 2021 125sx.

I prefer the 125, the 150 is fast and great fun but requires you to be playing god save the queen on the gear box while the 125 revs harder and further.
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Zycki11
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Zycki11 4/3/2021 7:09am
4/3/2021 7:09am
125 lectron carb and then buy 150 head. Twist and have fun
sebastianer 4/3/2021 7:48am
4/3/2021 7:48am
If you wanna have the ultimate small bore bike, i would buy a 150 and have the cylinder and head sent to Two Stroke Preformance in AU and have him do his magic on it, he is one of the only 2 stroke tuners in the world that actually puts out the results what his cylinders do, and i would say he is one of the best there is. he did an 150 for some years ago that put out 46whp with more power the whole register than stock (Stock was 40hp)
TeamGreen
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TeamGreen 4/3/2021 9:39am
4/3/2021 9:39am
erik_94COBRA wrote:
125 so you can buy 150 kit later if you'd like. Have to buy individual 125 parts.
This!

Riding them both back-to-back is an eye opener: The 125 actually “seems” faster and has a harder hit. The 150 reminds me of the older 200 engine...it’s for some mid-range torque (by 125 standards).

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Bruce372
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Bruce372 4/3/2021 10:39am
4/3/2021 10:39am
I own both a 125 and 150. It's really splitting hairs to compare the two, but its very easy to spend money and mess up the 150 lol.

Most of the aftermarket silencers actually loose top end power both on the the dyno and track.

Vforce makes zero difference on the dyno.

Mikuni runs really good on both bikes once setup.

Running the keihin fitted with STIC block, the 150 will over Rev very, very well.
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Bruce372
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Bruce372 4/3/2021 10:41am
4/3/2021 10:41am
Both 125 and 150 were have are fitted with fmf fatty and pc shorty. The 150 has the keihin, and there is no way shape or form the 125 feels anywhere as fast or powerful. We've had these bikes for 2 years and ridden plenty of tracks and trails to compare.

Either way, you can't go wrong
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wrc777
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wrc777 4/3/2021 3:39pm
4/3/2021 3:39pm
Buy the gasgas 125 and a 150 kit and get both for about the same price as either ktm.
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Bruce372
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Bruce372 4/3/2021 3:40pm
4/3/2021 3:40pm
wrc777 wrote:
Buy the gasgas 125 and a 150 kit and get both for about the same price as either ktm.
That's a great idea because the gas gas looks bitchen
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fanger
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fanger 4/3/2021 4:07pm
4/3/2021 4:07pm
Zycki11 wrote:
125 lectron carb and then buy 150 head. Twist and have fun
As a 125 nuffy I'm gonna need to hear the science behind this and why should do it. Sounds like an awesome way to get more out of the bike.
Zycki11
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Zycki11 4/3/2021 4:16pm
4/3/2021 4:16pm
Zycki11 wrote:
125 lectron carb and then buy 150 head. Twist and have fun
fanger wrote:
As a 125 nuffy I'm gonna need to hear the science behind this and why should do it. Sounds like an awesome way to get more...
As a 125 nuffy I'm gonna need to hear the science behind this and why should do it. Sounds like an awesome way to get more out of the bike.
https://www.lectronfuelsystems.com/why-lectron/
tsmitty2661
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tsmitty2661 4/3/2021 4:35pm
4/3/2021 4:35pm
I bought a 2019 KTM150sx. I love it, and im coming off a 2007 cr125 that was recently converted to a 144. I had one, well two, complaints with it. The 150 signed off on the top end if you tried to over rev it. I cant speak to the 125 but from my experience with the CR the 144 didnt rev as far as the 125 set up (wish i would have did 134). I sent the top end to Lynks racing and with new top end it was $675. Night and day difference, i was extremely impressed, no more complaints of signing off when over revving. Second complaint was the air fork nonsense, just put a race tech spring conversion in last weekend.

Some people mentioned above to get the 125 then the 150 kit, sure that works but when will you go through the time and work to switch everything over unless youre waiting on parts or getting the cylinder replated. My cr i have the entire 125 top end and 144 top end, never once switched it back and forth lol. I see your from japan so lynks might not be the most ideal place to send it but that would be my recommendation versus buying 125 then a 150 top end.
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piscokid 4/5/2021 9:44am
4/5/2021 9:44am
I have to weigh in on the Lectron. Not needed unless riding with major elevation changes, they just don't add any performance. If your bike runs better with a Lectron, the carb wasn't set up correctly. Lectrons are great for elevation changes (starting at 1000ft and riding to 3000ft for example) because they don't have jets. Save some money, buy some jets and set up the carb correctly. it takes some effort, but the results are mind blowing when the carb is set up for the fuel mixture being run and the bike itself.
SmokinJoe439 4/5/2021 10:10am
4/5/2021 10:10am
Get a 150 might be a little biased since I have a 21 150sx. I put the pwk with the jd jetting kit on it and it's sweet. Last little tweak it needs is gearing.
Stock it comes with 13/48 the 125's come with 13/50.
The stock 125 gearing ratio is 3.50 the stock 150 ratio is 3.64.

Which makes the 150 sign off sooner it's geared more for acceleration. So it feels like it winds out faster on top giving it less of an over rev feeling.
Changing the front sprocket to a 14t will make it the 3.50 ratio like the 125. Same with putting a 46 tooth rear on it. It has the power to pull it easily.

This will make it feel more like how the 125 does.
Faster riders will appreciate this or skilled small bore riders over lesser skilled riders.
I did this to my 2006 yz125 when it was 144'd as well.
Darrin Willis
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Darrin Willis 4/5/2021 11:40am
4/5/2021 11:40am Edited Date/Time 4/5/2021 11:42am
SmokinJoe439 wrote:
Get a 150 might be a little biased since I have a 21 150sx. I put the pwk with the jd jetting kit on it and...
Get a 150 might be a little biased since I have a 21 150sx. I put the pwk with the jd jetting kit on it and it's sweet. Last little tweak it needs is gearing.
Stock it comes with 13/48 the 125's come with 13/50.
The stock 125 gearing ratio is 3.50 the stock 150 ratio is 3.64.

Which makes the 150 sign off sooner it's geared more for acceleration. So it feels like it winds out faster on top giving it less of an over rev feeling.
Changing the front sprocket to a 14t will make it the 3.50 ratio like the 125. Same with putting a 46 tooth rear on it. It has the power to pull it easily.

This will make it feel more like how the 125 does.
Faster riders will appreciate this or skilled small bore riders over lesser skilled riders.
I did this to my 2006 yz125 when it was 144'd as well.
Your math is way off .
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Darrin Willis
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Darrin Willis 4/5/2021 11:44am
4/5/2021 11:44am
The gearing is already taller on the 150.I have a 21as well. I too am considering a 14/50 combo to stretch out between shifts.

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