2021 250 or 2021 KTM 150sx

IanMac138
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IanMac138 7/31/2020 10:24am
7/31/2020 10:24am
IanMac138 wrote:
If you buy the 150, I recommend throwing the Mikuni carb away and getting a Lectron or ANYTHING other than the POS Mikuni that comes on...
If you buy the 150, I recommend throwing the Mikuni carb away and getting a Lectron or ANYTHING other than the POS Mikuni that comes on it. I would also recommend adding 1 tooth to the rear sprocket (stock is 48 so go to 49) along with the Moto Tasinari V Force 4 reed valve system.

I put a Lectron on my bike and have never looked back...gave more low end torque and spread out the power. Adding 1 tooth to the rear sprocket allows me to carry tighter corners in 3rd gear with a slight feather of the clutch if needed before the afterburners kick in. The 48 tooth had me shifting down to 2nd in tight corners, which made me have to blow through 3rd and click to 4th on jump faces. Not fun. Now I can lug it in 3rd, feather the clutch and click to 4th before a jump face with ease.

Lastly, I recommend the FMF 2.1 Powercore silencer and FMF pipe. This combo, along with the Lectron and V4 reed cage made my bike bark, never bog and straight up changed the power delivery from the stock. She sounds like a screaming dragon and runs super clean. Oh, and I run 50/50 clear 92 octane with VP 110. She rips.

Cheers.
AJ565 wrote:
Man, thats a bit harsh on a really good carb just because you don't know how to jet it. Everyone I know that put a Lectron...
Man, thats a bit harsh on a really good carb just because you don't know how to jet it.

Everyone I know that put a Lectron on for moto took it back off because it deadens the hit and doesn't pull as hard.
I know a ton of fast dudes who run the Lectron and love it so its another one of those subjective things. I live in Oregon and was tired of the bike running good in the morning and shitty when it warmed up, or at different elevations the bike would hiccup, bog, ping depending on where I was at. I jetted it multiple times and even did the slide fix and while it helped, it didn't run exactly the same all the time. I know the Mikuni is a good carb when it's jetted right, but its fickle with temperature and elevation changes in my experience. Cheers
MxKing809
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MxKing809 7/31/2020 2:23pm
7/31/2020 2:23pm
DirtyThirty4 wrote:
Really need help with this debate I’m having. I’m 5’5” and 155 Ibs. I currently ride a 2010 kx 250f and I love it. But I’m...
Really need help with this debate I’m having. I’m 5’5” and 155 Ibs. I currently ride a 2010 kx 250f and I love it. But I’m buying a new bike this year and I really miss riding 2-strokes. Any help or opinions would be greatly appreciated.
Mx451 wrote:
Hello doppelganger i am considering the very same thing. Except I'm 5'11 185lbs.
scott_nz wrote:
im 6 ft 188 pounds, and love my 150, perfect bike,
6 ft - 195lbs and picked up a leftover 19 150 this summer for cheap. My 450 is for sale.

Only issue I’ve had in the last month is a stretched throttle cable and sore checks from the perma-smile.

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HighPlainsSquid 7/31/2020 5:08pm
7/31/2020 5:08pm Edited Date/Time 8/1/2020 12:39pm
EDIT: I am an idiot. I see now that the OP was asking about the 250 TWO STROKE and not the 250 (whispers) four-stroke. Nevertheless... I will leave my worthless effusive post up for posterity.

We have both- son has an '18 KTM 250 SX-F and '19 150 SX . I have a '14 KX250F and '15 Husky TC 125 and '18 KTM 150 XC-W.

For tracks and to ride competitively there, the 250F. Here's the difference.... on my 125, I have to ride AS HARD AS I CAN to keep up with my son on his 150 and he'll just walk away from me corner by corner by corner. The first time I took the 250F out, I _passed_ him. And I waved as I did it!!!! And he couldn't catch me again!!!! It was sweet. A few weeks later, he had his 250F and lapped me in 10 laps. Corner speed and traction is the big difference.

Off-road... in enduros, we both prefer the 150's. They are so flickable and light and easy that at the end of the day (80 miles) we're much less tired. Guy we rode with in the last enduro rode his 250F on Day 1 and after watching us, got his 150 SX for day 2. On the 150's, son has won Overall C at every enduro this year, I've taken 2nd place in 50+ and won a couple of stages.

Now for FUN on the MX track... well, ride whatever you want. I love passing 4S on my screamin' little 125, but there's no question than an equal rider on a 250F will smoke me. Just look at my son's example.

1
TeamGreen
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TeamGreen 7/31/2020 5:35pm
7/31/2020 5:35pm Edited Date/Time 7/31/2020 6:24pm
TeamGreen wrote:
I've ridden all the new SX and TC models. Believe it or not, the 125s are faster than the 150s.
HondaFan33 wrote:
Could you please elaborate on this? I’m currently in the midst of the same debate. I’ve heard that the 150 doesn’t seem to pull as long...
Could you please elaborate on this? I’m currently in the midst of the same debate. I’ve heard that the 150 doesn’t seem to pull as long but figured mods could sort that out if it bothers me.
About my day on these bikes...

Hangtown. Rutted up and in typical race day form...

Hitiing the rollers and bigger jumps, the 125 "on the pipe" was faster and hit harder with a longer pull than the 150. The big "Fly Jump" was certainly easier on the 125. Turns, for me, were faster on the 125 when I kept it in "the meat", too.

I see that others are apparently more "informed than I'; so, i leave it to them to share their expertise and tell me how wrong I am. The 150 was "torquier". It has what I would say felt like "good off-road" power and I'd even say it was easier to ride. But, in "stock v. stock"...I was getting better lap times on the 125.

On this particualr day, I got to ride the WP suspended bike they had for the ride...a 350 SX-F...my god...what a great bike.

My daily rides: 2019 KTM 450SX-F (Track), 2020 KTM 450SX-F w/14-48 gearing/KTM MXGP tank (Dez) and Husky FE350S for trail and fun. My ocassional smokers are a TE150 and a KX500.

ps - I got to ride the 150 and 125 "back to back to back to back to back to back" in stock form on T2 fuel (read "brand new" bikes, too).
1

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powertrip456 7/31/2020 6:07pm
7/31/2020 6:07pm
IanMac138 wrote:
If you buy the 150, I recommend throwing the Mikuni carb away and getting a Lectron or ANYTHING other than the POS Mikuni that comes on...
If you buy the 150, I recommend throwing the Mikuni carb away and getting a Lectron or ANYTHING other than the POS Mikuni that comes on it. I would also recommend adding 1 tooth to the rear sprocket (stock is 48 so go to 49) along with the Moto Tasinari V Force 4 reed valve system.

I put a Lectron on my bike and have never looked back...gave more low end torque and spread out the power. Adding 1 tooth to the rear sprocket allows me to carry tighter corners in 3rd gear with a slight feather of the clutch if needed before the afterburners kick in. The 48 tooth had me shifting down to 2nd in tight corners, which made me have to blow through 3rd and click to 4th on jump faces. Not fun. Now I can lug it in 3rd, feather the clutch and click to 4th before a jump face with ease.

Lastly, I recommend the FMF 2.1 Powercore silencer and FMF pipe. This combo, along with the Lectron and V4 reed cage made my bike bark, never bog and straight up changed the power delivery from the stock. She sounds like a screaming dragon and runs super clean. Oh, and I run 50/50 clear 92 octane with VP 110. She rips.

Cheers.
AJ565 wrote:
Man, thats a bit harsh on a really good carb just because you don't know how to jet it. Everyone I know that put a Lectron...
Man, thats a bit harsh on a really good carb just because you don't know how to jet it.

Everyone I know that put a Lectron on for moto took it back off because it deadens the hit and doesn't pull as hard.
IanMac138 wrote:
I know a ton of fast dudes who run the Lectron and love it so its another one of those subjective things. I live in Oregon...
I know a ton of fast dudes who run the Lectron and love it so its another one of those subjective things. I live in Oregon and was tired of the bike running good in the morning and shitty when it warmed up, or at different elevations the bike would hiccup, bog, ping depending on where I was at. I jetted it multiple times and even did the slide fix and while it helped, it didn't run exactly the same all the time. I know the Mikuni is a good carb when it's jetted right, but its fickle with temperature and elevation changes in my experience. Cheers
Whoaa... I have the ‘18 150SX and it was barely rideable with the Mikuni. I had one of the biggest crashes of my life because of that piece of shit. Sure, I could get it running perfectly some days, but not repeatable. I love that bike though and I do have the Lectron on it now. I’m sure the Keihin would have done it and I considered that, but I tried (what felt like) everything with the Mikuni first.

In my opinion the OP should probably get a 250 unless he wants one of each though.
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burn1986
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burn1986 7/31/2020 7:53pm
7/31/2020 7:53pm Edited Date/Time 7/31/2020 7:55pm
Edited, tried to post a vid of Musquin shredding on the 150, but I wasn’t able to embed it.
HighPlainsSquid 8/1/2020 12:44pm
8/1/2020 12:44pm
powertrip456 wrote:
Whoaa... I have the ‘18 150SX and it was barely rideable with the Mikuni. I had one of the biggest crashes of my life because of...
Whoaa... I have the ‘18 150SX and it was barely rideable with the Mikuni. I had one of the biggest crashes of my life because of that piece of shit. Sure, I could get it running perfectly some days, but not repeatable. I love that bike though and I do have the Lectron on it now. I’m sure the Keihin would have done it and I considered that, but I tried (what felt like) everything with the Mikuni first.

In my opinion the OP should probably get a 250 unless he wants one of each though.
I can jet pretty well myself, but after spending a LOT of time trying to get the '18 150 XC-W and '19 150 SX running clean with the stock Mikuni, I abandoned ship and tried a Lectron on my XC-W. I hate spending money- esp $500 on a carb for a $7500 "Ready To Race" bike- but 15 minutes into my first ride, I told my son "You're gonna want one".

According to our guru-base, I need to change the whole Mikuni guts into something else. Maybe someday I'll do that just to see but for now, the Miks hang on the wall.

We're pretty happy with the Lect's. Except for the fact that they cost $500 each. And before we say "SmartCarb", those are 40% more $$$. And STIC on a Keihin is 25% more than THAT. Remember,whatever I get for one has to be doubled for the other.

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dave_daum
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dave_daum 8/1/2020 5:35pm
8/1/2020 5:35pm
I'm a fast older 160 lb. B level single-track rider. I recently sold my YZ 250 and replaced it with a KTM 150 XCW. After a complete redo of the suspension and installing a Keihin PWK 39 carb I'm very happy. The 150 is much easier and fun to ride. I never feel like the bike is going to kill me. The 250 had just too much power for woods and single-track riding. I can flick the 150 around and it feels light as a feather.
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dedi684
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dedi684 8/1/2020 6:13pm
8/1/2020 6:13pm
dave_daum wrote:
I'm a fast older 160 lb. B level single-track rider. I recently sold my YZ 250 and replaced it with a KTM 150 XCW. After a...
I'm a fast older 160 lb. B level single-track rider. I recently sold my YZ 250 and replaced it with a KTM 150 XCW. After a complete redo of the suspension and installing a Keihin PWK 39 carb I'm very happy. The 150 is much easier and fun to ride. I never feel like the bike is going to kill me. The 250 had just too much power for woods and single-track riding. I can flick the 150 around and it feels light as a feather.
Im the same but vet moto rider. Been riding yz 250s for 20 years such a handful but fast. Thinking of a 150 cus im down to about 150 pounds.
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BToz
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BToz 8/2/2020 6:40am
8/2/2020 6:40am
If you get both then post what you like about each. The 150 sx might have 40-42hp(?) but that high number probably lasts for about .03 seconds just after you feel power coming on then you’re starting to over rev. My bike has 1st gear, 1.5 gear, 3rd, 3.75, 5th and 5th. It is a fun bike but I’m more comfortable with torque and I don’t have anywhere near the ability to keep the bike in the sweet spot and rip around a track or trail. I’m actually running a tooth smaller rear sprocket. I have stock and 1 tooth larger as well. I don’t think the carb is bad -Mikuni- but I’m thinking about the stock 2016 carb and trying it to see if it’s really that much of a difference.
moore433
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moore433 8/3/2020 4:16pm
8/3/2020 4:16pm
TeamGreen wrote:
I've ridden all the new SX and TC models. Believe it or not, the 125s are faster than the 150s.
Suzukifan2019 wrote:
BS dude, the 150 is way faster than any 125 you can find. Like some pro have said, riding the 150 is like riding a factory...
BS dude, the 150 is way faster than any 125 you can find.
Like some pro have said, riding the 150 is like riding a factory 125.
I had one for almost a year and i feel that it was competitive against 250F,
but the torque and the traction is not as good as a 4stroke.
The 250 SX on the other hand must have a lot of torque and you can ride a gear higher.
Regarding 2021 bikes, 150 are gonna be hard to find ! available in november (my ktm dealer told me this)
Cycle Center of Denton in Denton tx has them. And I just picked up a 2020 ktm150sx Friday from Munn Racing in Tx and got a good deal too!!!
731chopper
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731chopper 8/3/2020 5:12pm
8/3/2020 5:12pm
I've got a 2016 150 SX. I love the ergonomics of the bike and I like to scream bikes probably more than I should so if I could swap the bike for a 125 I would. The meat of the power is great but it is about as narrow as the edge of my pocket knife and it isn't at the top of the RPM so it doesn't ride exactly like a 125. I've had a great mechanic jet it, rebuild the top end, adjust the power valve, add a v-force but nothing has really helped it. After talking with other 150 owners, I'm not alone. Some people says there's aren't this way so I don't know if KTM is just inconsistent with their motors or what.
PJRAUS
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PJRAUS 9/23/2020 11:40pm
9/23/2020 11:40pm
TeamGreen wrote:
I've ridden all the new SX and TC models. Believe it or not, the 125s are faster than the 150s.
Just wondering if you could talk a little more about that...I too am a bit interested in a ktm 150..
Probably wouldn't race it...I have 6 other bikes..but just your opinion on why the 125 is faster as a race bike and which would you prefer ,purely as a fun bike to ride at the track with your mates..
Thanks..
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