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I guess that’s why all high performance cars run carburetors. Yep
Love my 25 300sx with a pipe and silencer. Stock pipe and silencer killed the overev. Faster than my 350sx.
Rode a 300xc at a demo day. Very fun woods bike. Turned amazing and linear but strong motor. Haven't got to ride a 300sx yet.
70 hours on 24 250xc
Tires, filters, and oil.
Things rips. Probably never go back.
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Which pipe and silencer?
Currently Pro circuit factory pipe and Kevlar shorty. I also used a FMF fatty and titanium silencer. Both worked the same.
I also have a ‘24 250xc. Mine ran really rich new so got the TSP tune and a mid-compression head. Cleaned it up and runs great. I’ve got 115 hours on it, replaced oem chain and sprockets at 80 hours, top end and clutch at 100 as preventative. I keep thinking its time for a new bike, but do not know what I’d replace it with, it’s just damned good.
I have a ‘23 250 XC-W TPI that I love. Super smooth power, also smoother because I went down two teeth in the rear to give each gear a bit more speed.
It’s ran great, perfect to ride all four seasons. It took me a bit to figure out the suspension compared to my ‘15, but I’m 25 lbs lighter and a decade older and slower. I’ve got almost 160 hours on it. Most use has been on turn tracks and twisty single track.
I love the ergos and feel of the bike, which has kept me from going TBI, even with the reports of better suspension.
OMG.. I told you why and you didn't even bother to do a 5 sec google search to learn something, and it is obvious you know little about racing or performance engines, otherwise you would know that some NASCAR teams still use carburetors, they are used a lot in drag racing and making a fairly big comeback since carbs deliver such a good bang for the buck when team budgets get tighter, and carbs are also still used quite a bit in circle track racing. Carbs are not outdated and they are still very good technology. For OEM manufacturers, EFI makes sense for many reasons with reliable, fuel emissions efficient performance at varying altitudes and a very broad range of outside temperatures. It is NOT because FI makes more peak power than carbs.
KTM's are only using TPI which is considered rather antiquated, as far as fuel injection systems go, in the performance automobile world.
If you buy one stock! They are slow first!! And if you try to do a start, they can’t hold a constant RPM!! The RPMs go up and down up and down!! if you get the ECU updated, they’re not too bad!!! I’m talking about the 125!!! The 250s aren’t quite as bad!!
Mxa did a test between a built yz250 and a yz250f. The built by xpr yz 250 made 53 hp.
The ktm 250sx makes those hp numbers from the factory. As shown by tsp performance.
Ill add that those number are on the 23 models. The tbi has gotten better and better each year. Carb 2 strokes are awsome but this myth that the FI bikes are slow is just that. Numbers dont lie.
What are you trying to say????? That test is not a straight up comparison of fuel injection vs a carb so irrelevant.
The carb yz 250 needed substantial work done to reach the same hp numbers that the FI bike of the same displacement makes from the factory. So im saying that your argument of the carb making more peak hp is false.
Owned a 23,24,25 sx300 after many years of carbed Ktm’s. Absolutely loved them, my local dealer stopped being an Austrian dealer so I picked up a 25 yz250. Yz is absolutely a fun bike but is pals in comparison as a race machine to the ktm 300sx. I’ll be back on the ktm300 for my next bike.
I’ve got some video racing them both at the same track. The ktm was from 2023 and the yz was 2025.
You guys are idiotic.. you can't declare a generality by one single example that is completely apples to oranges. You should be smart enough to know that. It well known in auto racing what I am saying and you will find tons of articles on it by top performance auto engine builders on the internet about carbs better atomizing fuel than FI, and I am not going to argue with someone who won't do the research just to hold onto a ridiculous unsubstantiated point.
Pit Row
You’re delusional. There has been many private dyno runs posted showing a yz250 makes more hp then a TBI 250sx. And older non-counter balanced 250sx making more than both and they also weight less then a tbi.
I don’t need to do a goggle search. Carburetors can have certain advantages but overall they are not better. In the performance auto world carbs are not better even if some nascar team uses carbs. KTMs system isn’t cutting edge, it’s a cheap dirt bike. But guess what they run great, I actually own one. Guessing you just “google” all your info.
Glad to see I've revived this thread. But does anyone have any information on the parts? Anyone happen to work at a dealership or something?
What we are saying is….if you maintain the bike properly you will get 100+ hrs out of each top end & clutch…I have never had to replace anything more than normal maintenance items….tires, chain & sprox, brake pads, chain guide & sliders…I sell mine around the 150hr mark but usually to friends who continue riding them…I have never had to replace a clutch hard part, trans gear, or crank in a late model KtM…I have been a Honda guy and Yamaha guy in the past….my last 2 YZ250 2 strokes were great bikes but clutch hard parts and transmission gears did not make it through the season, I don’t want to split cases mid season on my race bikes….
You are comparing Dyno runs done at different times, by different people, on different Dynos, and even on different continents. Not exactly a conclusive test. Here, try this one.. LOL
So then the opposite side of the argument cannot prove that the carb bikes makes more power then?
Do you have a TBI 2-stroke?
Yes. After 2 yz 250s.
I wish you the best of luck with it. But do promise us that you will come back here and let us know if it has some massive headache of a problem like so many other TBI bikes have.
Absolutely. I like dirtbikes. Have been riding and owning every brand and displacement from 80s to 450s. I have no allegiance to brand or displacement. The tbi 2 stroke is not slow, underpowered or lacking compared to a carb bike. The people that get on the internet and claim this are butt hurt for whatever reason.
So far in 70 hours I have pushed the button and it has ran perfect everytime. No sputter no glitch, nothing. This is my testimony. I have tried to produce some numbers to back my claim but dynos apparently are misleading unless its to support your argument. So the seat of my ass argument says the tbi is a more powerful machine than the 2 yzs I owned before. Thats not a slight on the yz.
I’ve got 50 hours on my 25 Ktm 300sx. Best bike I’ve ever owned. Power delivery is amazing. Lends itself to smooth flowy riding style and I love everything about the bike. Had a top end done at 30 hours because I thought it was necessary but once pulled apart realized it didn’t need anything.
air filter and frequent oil changes and let her eat
It seems like the people racing them at a high level get them to run ok on the ground but in the air the bike sounds horrid - seems to be vacillating between rich and lean and they can’t seem to rev cleanly in the air -
I keep thinking they must be scary as heck to ride .
I wonder if that’s why most of the national level schoolboy kids have swapped over to YZ 125s
Post a reply to: Feedback on New Fuel-Injected KTM Two-Strokes?