2023 KTM 350 SXF or 2023 FC 350 handling issues?

Redmoto has a Honda 400 kit so it should be possible to make something a little smaller than a 450 out of a 450 engine. 350 might be a little too far from a base 450 engine.

I went from a 70 hour 23 300sx to my new 24 300sx. Put my cone valves, trax shock and wheels on it so perfect test of frame stiffness. I’ve never had a new bike feel so identical to my old one as this. I did the exact same thing from my 2017 to 2018 and it felt way stiffer. 

Yep. I feel it also.  It's always been there, just not as bad once bike dialed in. I can live with it, I just think I know what you mean. 

Over the hols, I am gonna do a back to back with my 2020.5 on the same track over a weekend. 

Mine is jump landings.  That's usually a sign of shock setup, but I went in on high speed adjuster and nothing changed.  

I notice something,  but i don't know if it's a problem or if it's me. I can live with it.

Mako 360 mounts were a game changer for me. It’s weird how much the bars move with the bike on the stand but I don’t notice at all when riding. I’ll never have another bike without them honestly. I’m guessing flex bars are good too but I can’t speak from experience on them. 

I have the mako 360 setup also had on my 22 450 now on my 24 350. I have carpal tunnel real bad and has helped more than anything I have ever used will always use them 

I wonder if stiff feeling is from chain binding??? Watch last 5 mins of this ....

Wondering if he has the right chain slack for 2023? Because having the chain that tight I think you would have heard more about chains snapping or gear being broken. 

Just saw he says he has it looser then spec

@Luxon MX curious to what your view on this is?

Sounds strange that KTM would have missed this or designed it that wrong?

I assume you're asking about the chain tension issue from the video? If so, yes, that's pretty bad!

The variation in tension is normal for most all bikes; the only way to not have any variation would be to have the countershaft sprocket in the same axis as the swingarm pivot, which isn't terribly easy to accomplish... But the current KTM is really bad! I'm not sure the correct fix is different valving, I'd just run even more chain slack to remove any over-tension in the chain throughout the shock stroke. It's going to look REALLY loose just sitting on the stand, though. 

The slack variation is entirely dependent on the countershaft sprocket location to the swingarm pivot and, to a lesser extent, the sprocket sizes. The only other potential fix beyond a really slack chain is an engine re-location bracket/mount system, but that's easier said than done as a lot of parts are fit dependent with the current engine position. 

I run 14 tooth countershaft sprockets on both of my 24's as well as proper slack. I don't feel any problems myself.

This is a well-known problem, The manuals were completed with the incorrect measures. Simple fix just run the chain looser. I've been running 70mm slack for a good year and a half on mine and never had a problem.  Keefer did a video on this a year ago when they first came out.

I don’t think they missed on design, I think they were trying something different. The counter shaft height to pivot location changes the bikes anti-squat and anti-rise characteristics.  This bike doesn’t squat like the current Japanese bikes under load.  
 

A negative characteristic is the axle path lengthening, which is why the chain slack gets tight.  
 

I understand the idea behind less squat, but also understand why it’s bad in some areas.  With the correct slack in the chain, it won’t bind as much as in the JBI video and yes it’s possible that his valving could help that feeling.  Like Billy wrote, the only true “Fix” to change this characteristic is adjusting the height of the counter shaft to the pivot. It’s crazy, but we are talking a few mm could be all it needs.

I know they went to anti squat theory for new chassi, but chain tension is not part of the anti squat, it can't be.

If you just go by the video, he says he has the chain less tighten than what is recommended. Anymore, and it risk jumping off.

I will check my 2022 tomorrow, shock is of that one and see how chain slack is. But it seems very little margin for breaking the chain. Just some dirt or minor stone and it will snap or destroy gears. But I have not heard about that happening so again, maybe not a real issue.

You could of course just test it by relaxing chain even more and see how suspension behave. Should be quiet noticeable if it actually has any impact.

Every bike chain tightens when the wheel goes up. You can set too tight of a chain tension on any bike and get what he is showing in the jbi video. Does he ever show what his chain tension is at full shock extension? The ktm manual is off by close to 10mm. You need 65mm minimum slack at full shock extension or the chain will bind during the rear suspension travel. I don’t know why it hasn’t been fixed in the manual. They have had time to update the 2024 manuals with the factory edition settings but not fix the chain slack setting range.
 

Also under engine load the top of the chain is always tight. That is probably one reason why the 250f ktm feels less rigid than the 450. I have cycled my suspension with 65mm slack, and it is okay but I wouldn’t run any tighter than that. 

I wonder if the "frame loosening up after 10 hours " is actually the chain wearing and freeing up the back end a bit.

Also,  so many people complain about fork setup on ktms and my experience is that it's shock setup making the forks feel off... at least on the older version, new chassis shock seems to hold up well, first time I've not felt need to revalve a shock in years 

The second video with Keefer shows the rear wheel moving and the chain still having enough slack to go to bottom out.

I’m hoping keefer using the 65mm bolt is actually closer to 70mm, because I’ve been running a measured 65mm and am hoping that’s been my issue with the rear end ramping up on acceleration bumps. That 65mm bolt is probably closer to 71-72mm from top to bottom (depending on if he used an actual 65mm bolt, or measured a bolt that is 65mm in total length)

almost like when I mentioned a possible issue with counter shaft location being lower than last gen frame and that the frame wasn’t actually stiffer i might have been on to something… my guess is a higher CS sprocket in 24.5/25 bikes but who am i? I’m just the guy that can tell a difference of 1NM in my lower triple clamp bolts and a fork shim behind the motor mounts 😂

You are spot on with your review. Same experience for me,  Last years, I rode SXF 350 2017,,, follow by a 2019,,, and I prefer to buy the 2022 version with 6 hours on it at the same price of a 2023.  

Oh,,, just to be honest,,, the 2022 is equipped with a full Ohlins suspension.

For a KTM enthusiasm like me, I didn't gel with the last gen. 

I just overlaid last years FE and the new one and I can see any change in engine position . but a few mm that I can see in a photo could make a difference.

The 3mm lower cs sprocket is still listed as a feature on the factory edition as copy so I doubt they moved the engine but ktm has lots of typos on their sites so maybe they changed it but I bet not. Just run at least 65mm chain slack at full extension with shock on and it will have enough slack unless you get a lot of mud on the sprockets. If you don’t trust the 65mm measurement, take the shock off and find the minimum chain slack that gets the chain freeness you want through the suspension travel.  Then check it with the shock on and stick to that chain slack from now on. It will look loose and people will tell you your chain is loose. 

If anyone is interested, I just installed the 6500 insert fork on my 24 450 and took it to the Glen Helen main track Tuesday.

The afternoon conditions there are just brutal for any suspension, and this could be just my perception, but the bike seemed substantially more compliant down the hills and into the square edge corner chop with the spring fork.

 I wasn't looking for comfort as much as I was stability on a track like this - the bumps and rocks there get so bad, they can almost rip the bars out of your hands at speed sometimes.

I changed the fork at the track and rode them back to back - the stability that the re-valved spring insert fork has over the stock air units seemed significant to me.  I really like the air fork a lot for smoother faster tracks like Cahuilla or Elsinore, , but the insert fork sure made the afternoon at Glen Helen less scary.  

I can say that the new frame feels so much more stable and balanced over the previous gen 450 ( I still have one of those).  

This is just my amateur opinion, but after spending time on this new bike I think that the new KTM frame is built more for performance rather than comfort.  I know there are links available that make this bike feel more progressive, I'd love to try one sometime.