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Only $10 for all 2026 SX, MX, and SMX series.
the 52 uses the same internals as the WP Xact Pro 7548
Shims provide ultimate variations of any stiffness. They fatigue- not that much. As reliable as any other leaf spring.
King shocks idea seem like ultimate.
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Luxon 4-Post Bar Mounts
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DeCal Works Huge Plastic Inventory of UFO and Polisport kits.
I found my 21 TX felt almost as good as a spring fork on smoother tracks but really showed their weakness in the hack and slap downs. Part of that may be Valving. I use my bike more for offroad than MX so ended up getting a set of Luckies. Also had too many issues with the air side leaking. Dealer tried to fix it once, now it’s at WP waiting for a fix.
Sag set up on the KTM /Husq/GasGas is critical.
Free sag should be 30 to 38mm and race sag should not be over 103mm.
Any more sag and the bike rides like a chopper because of the softer rear spring and linkage ratios.
I can tell you that because of the KTMs link ratio and the stock 4.5 NM spring, it is really easy to overload the rear suspension if the sag is below 103 or 104.
I have been doing a lot of testing with my WP shop with both a modified AER 48 air fork and the WP Cone valve fork, and believe me the sag make a huge difference with how the bike handles and how the forks work.
If the back end is low, the front end Choppers out and the fork won’t work correctly.
Some faster guys like Kris Keefer were running 95mm sag with the stock link and knuckle. I’m using REPs longer link and I find the sweet spot between 100 and 103 sag.
Also, if you weigh more than 170 with no gear ( remember gear adds 20 lbs) you should change the shock spring to a 4.8 NM .
Pit Row
My criticism is we have a situation here where that dynamic has become inverted, the KTM factory riders are not using it and the production bikes are. Successful bleeding edge tech usually comes top down, not bottom up..
I‘m also a fan of the aer forks. The separation of air spring and damping circuit keeps the air spring at a fairly constant temp and therefore spring rate. It‘s very adjustable and overall works fine. The only thing I don’t like its feel on slap down landing. However, I don’t think that has anything to do with the air spring and more with the quality of the bushings and so on.
And sandhills point was that coil-sprung suspensions had taken on all comers and emerged victorious. That's simply not true. Even if they are using a "spring" in F1, it's not a coil.
Additionally:
Not to argue, but until someone shows me a current F1 car with a traditional steel coil spring I'll maintain my position.
I agree through the air pressure setting has a huge influence on the fork feelings. Moto ready to trail ride ready in a few minutes is a nice feature. If I ever start playing with shim stacks the ability to revalve in half the time of a dual coil fork will be nice.
But you’re right: a coil spring surely isn‘t the best solution for everything. It takes more space than a torsion bar and can‘t do the things a belleville washer setup can do (but is cheaper than both).
as this video states DF14 is on KYB PSF1 forks
Post a reply to: Will KTM / WP ever give up on trying to reinvent the fork?