A KTM 250 SX-F headpipe on a KTM 350 SX-F? Why?

[@yuriabmxr]

I ran a KTM 250f head pipe on my GasGas 350 years ago. Worked great!

[@Lowyn42]

I'm on a 2022 350 so I didn't think this video was for me. Till I saw those legs tho 😍

[@Evo836]

Yea rooster legs

[@douglayman1843]

Keef been skipping leg day lol😂

[@codyhosta7404]

FMF just sold out of 250 headers. 🤣......good stuff Keefer.

[@Kawiboy]

Facts 😆✌️

[@Moffattfamily-316]

I did this with my yoshi exhaust a couple months ago when bought my 2025 ktm350

[@seangavingregory4367]

Stock muffler with Yosh head pipe? I wonder…

[@grantcovey3144]

Will this set up work on a husky as well?

[@jhheintz450]

As always thanks for the intel! Assume this works for the new Husky as well. Can you speak to the difference in going this route vs getting a mapped Vortex from Chad or Jamie? Thanks

[@Keeferinctesting]

@@jhheintz450 This isn’t as drastic as a Vortex ECU but does “wake” the power up some. This is also same for all Austrian brands.

[@BAYAREAMX]

Does this work on the previous 350’s? 2022 and older?

[@Keeferinctesting]

@@BAYAREAMX Yes

[@codysmith9385]

So could you just purchase a full system 250 exhaust (header&muffler) and bolt it to the 350

[@Keeferinctesting]

@@codysmith9385 You could but the muffler is diff. Runs better with 350 muff and 250 HP.

[@barnescycle]

Would the stock 250 header give more power then the stock 350 as well?

[@barnescycle]

Can i buy a 350 cylinder and make my 250 a 350?

[@331brents]

If i bought a stock 250sxf header and put it on our stock 350sxf would it have more snap on the low to mid?

[@Keeferinctesting]

@@331brents I tried the stock 250 and it didn’t change much. 😫

[@polaridoo1]

The KTM 350s Achilles heel has always been lack of bottom end regardless of the year. This becomes really apparent at altitude and when you are heavier than 160 pounds. Fun bike but I wasted too much time and money trying to make it 350 have better low end. If you're big, just buy a 450.

[@westcoastfrisco]

The 23+ 350s have a substantial amount more amount low end compared to 22 and earlier imo. A tuned Vortex, full system, they haul my fatass around great.

[@seangavingregory4367]

160 lbs is “big”? Lol

[@polaridoo1]

@@seangavingregory4367 Nope. 160 is light but if I weighed more than 160 I wouldn't waste my time on the 350. I'm 220 and it was severely lacking. If you're over 160 lb and can't handle a 450, stick up potato in the exhaust. Cheaper than trying to make the 350 have low end power.

[@westcoastfrisco]

@@polaridoo1 Im 230 geared up and my 350 is tits. Cant lug it like a 450 obviously, but its waay more agile in the woods/single track

[@westcoastfrisco]

@@polaridoo1 the winning rider in GNCC history was on a 350 so I think they’ve got enough power

[@westcoastfrisco]

Now would a 350 header give a 250 more top end? 🧐

[@MXROutlaw]

Good question. It might, but like he said the 250 header was shorter, so it'll be longer on the 250 so you might lose some bottom and gain mid/top range???

[@troygardner1294]

No opposite I did this from my dad’s 350 to my 250 and it killed the top end. Bottom to mid increased.

[@Pugman69420]

Are the mufflers not the same? They were on the 16-18 bikes

[@Keeferinctesting]

@@Pugman69420 Not same

[@hornefoundations]

I owned a 2016 350 xc-f and, now own a 2020 350 xc-f and, can say the pipes aren't the same. The older 16-18's had a longer sweep in the pipe off the cylinder and, had much more low end power. Hard to believe a shorter sweep off the cylinder would give you better bottom end...maybe quicker "recovery" like he say's but, bottom end?

[@2boyzracing]

So I'm wondering would a stock head pipe off a 250 do the same as the FMF ? And what would happen to the 250 if you put the stock 350 head pipe on that ?? Just wondering if I need to steal my kids head pipe off his 250😅.

[@Keeferinctesting]

@@2boyzracing Stock 250 HP will work but doesn’t have the response like the FMF 250 HP.

[@troygardner1294]

I tried this, the 350 header on the 250 increased the bottom end. Great for harescrambles/ enduro if that’s your style of riding, but you loose top end power big time. I personally wasn’t a fan of

[@Dirt_Serpent]

I ride a yz400f. My buddy just got a 2024 350xcf and after riding it. His bike has all the power he’ll ever need bone stock, I will say though that bike felt cramped and small to ride compared to my old yz400f.

[@leekirkpatrick6317]

Ive got a 2023 350 had a ti akrapovic with vortex.. the pipe done fuck all! If anything it feels better with the stock pipe

[@jeffdacey4673]

Way to do your research before dropping 1300 on a full exhaust lmao

[@leekirkpatrick6317]

​@@jeffdacey4673 who said I paid for it?

[@Keeferinctesting]

@@leekirkpatrick6317 Like I said in video Akra smooths out power. Well built system though.

[@moto3463]

Nice 👍🏼

[@buddysumner4022]

Humm,, I always thought longer head pipe was for more bottom end and shorter head pipe made more power on top end,

[@Keeferinctesting]

@@buddysumner4022 Usually the case but also sometimes volume of HP as well as bend makes difference as well.

[@buddysumner4022]

@@Keeferinctesting yep,, I guess it could,, some engines respond differently then other,👍

[@thelawnmanky]

Will this work on older models? Like 15 16 ect?

[@rileynielsen7472]

I second this! Looking for 2017

[@keithpeterson6108]

Longer headpipe shifts power towards bottom Shorter shifts it towards top. Put it on the dyno.

[@Keeferinctesting]

@@keithpeterson6108 Most cases yes. In this case with diameter and length of this 250 HP, it shifts power feel towards bottom and mid rpm recovery.

[@keithpeterson6108]

@Keeferinctesting I don't think the video made mention of the diameter change. Thanks for clarifying that detail. 👍