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6248
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11/25/2007
Location
Athens, GA, USA
Edited Date/Time
12/6/2021 7:50pm
Rode my new-to-me 2017 KTM 250sx for the first time today and love almost everything about the bike. Except how the front end feels. The forks didn't feel like they were traveling too fast through stroke, or too slow - they just felt like they were riding high in the stroke. This was especially apparent in corners.
Do folks get more comfortable with AER forks the more you ride them?
If not, I saw RT has a conversion kit but it's not cheap. I have a '16 KTM 500 EXC - could I potentially swap forks on these two bikes?
Do folks get more comfortable with AER forks the more you ride them?
If not, I saw RT has a conversion kit but it's not cheap. I have a '16 KTM 500 EXC - could I potentially swap forks on these two bikes?
I'm 155lbs and on my 17 350 have ended up at 125PSI. This, combined with a revalve makes the forks quite usable.
Being realistic they don't work as well as the Ohlins cartridges in my 17 125SX or the SSS forks of my YZ250, but they're far from being the poo that many have made them out to be.
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https://motocrossactionmag.com/mxa-team-tested-coppersmith-aero-hybrid-…
I absolutely plan to spend more time with stock AER setup, but I am not a huge fan of potentially having to fiddle with air pressure, compression and rebound clickers for every new track or riding area.
If the 2017 smoker came with a check valve also, I would just fit the updated 2018 air seal and seal head and be done.
Don't forget, the oil level is adjustable on these forks like regular ones.
I knew this bike had air forks, but no actually did not research AER forks before buying I just assumed that KTM would have awesome suspension.
When I rode the bike on a track for the first time the front end did not feel comfortable to me, it did not want to settle in corners and just felt weird. I have not checked or set the air pressure so obviously, before I go and spend $2,000 on fork upgrades, I will obviously do that. I got them working slightly better by backing out compression all the way I'm thinking that there's too much air pressure.
The rear sag was also too little so the previous rider must have weighed a lot more than I do. I set the sag to 105mm and that also helped a little.
Now that I know AER forks require fiddling from track to track, and from conditions to conditions, I am just thinking ahead for plan b and c. This is what intelligent people do everyday in life when potential problems are encountered.
Once set up, the AER forks do not require excessive tuning track to track. I basically never touch mine now that I have my settings where I want them. I just bleed and re-verify pressure each ride.
Start there lol.
https://www.youtube.com/watch?v=DSOd7SHvYPk
I also rode with a guy a few weeks ago who does suspension on the side. He used to race super cross a few years ago and was telling me stories about how he tested with ktm and they were able to basically get a bunch of insight on the AER forks. He said he revalves his personal ktms and loves how they work.
When you're doing your initial setup, there's a bit of playing around with the pressure and clickers. No different than a spring fork, save for getting the PSI (which is your spring rate) correct. Once that's set, it's just a normal fork. Checking fork PSI when you unload to go riding is no different than checking tire pressure- it's not normally off by much, if any.
Yes, my 125 has the TTX22 cartridges. They work well, but not as well as some KYB stuff I've tried out. I'm leaning toward one of the MX-Tech drop-in solutions for my 350. Got to sell my YZ250 first.
Pit Row
How does a properly set up TTX22 compare to a properly set up stock AER system?
Until you've set pressure to your weight, rebuilt them to make sure everything is working properly/is fresh, I wouldn't consider anything.
My guess is you need to drop PSI which will help get your weight were you need it. If you find a spot you like but are bottoming excessively, you can add more oil to the fork outers (ramps up sooner).
Regardless, I'm speculating. Start at the manufacturer's suggested baseline. Tune from there. Chances are we can get it with you spending no more than the cost of some oil. That said, if you don't like something, chime in; there are a myriad of options for you, ranging from very simple revalves to full on cartridge/spring swaps.
Admittedly, the Ohlins is in a 125 and the 350 has the air, but I recently decided to sell the 125, so maybe we'll drop the inserts in the Husky and I'll have a much better back to back comparison.
You can usually go with softer compression damping because the air spring has lots of bottoming resistance. That's where I'd start, if I were you. Back your compression clickers out several clicks and see if that helps. (Also, definitely start with the recommended pressures for your weight and speed.)
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