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Only $10 for all 2026 SX, MX, and SMX series.
The outer chambers only if you know anything about how the AER forks work that should be obvious
I have a 2024 KTM 350 SXF that I installed 2024 Husky suspension. Short legs… So the JBI kit is in 2024 FC350 forks. (I have the 2024 KTM XACT AER forks for sale - 12.5 hours on them).
Any idea how much oil to put in? Just looking for a little more glide at the top on the small chatter
I used 250ml 10w40 Motorex
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I just heard about this Glide Kit recently. Can you (anyone) confirm this improves 23 and later AER forks? I read the production forks had been modified to reduce friction though I don’t know what was done.
what I found with the glide kit - SKF is the SKF seals are different and just higher quality, and in 2 different bikes 2023 both needed less air pressure which helps putting the forks in the sweet spot. And after stating earlier using the motor oil in the outer chambers I have yet to replace a fork seal. Update my '23 xc350 has 125 hours and i put the kit in around 40 hours. The bike is working better than ever. I also set the sag closer to 100 rather than 105.
Do you put engine oil in the air side outer chamber or both sides?
Keefer recently had a podcast with chad from AEO on. Chad was saying they modify the seal on the air side. I think this is to reduce stiction and excessive stiction during pressure spikes as you move deeper into the travel. He also said though it reduces the reliability of the seal.
Both sides - as far as reducing the reliability of the seal nope they last longer. No idea how it could reduce reliability?
I didn’t say anything about reliability. I would be more concerned with any effects mixing the inner and outer oils might have on the dampening.
Mark from REP did indicate that reducing seal friction on the air side was helping the AERs. To what degree he didn’t really indicate. I’d like a sense of whether this is a minor improvement that you’d have to ride back to back to even tell, or something more significant.
Mixing? they never touch each other - the motor oil lubricates the outer parts the fork oil is inside where the valving is.
I always thought there was some transfer between cartridge and outer tube due to the cartridge seal not being perfect. Maybe not. The heavier oil in the outer tube will increase the dampening of the bottoming cones but maybe that makes it work better.
Lots of people (including suspension technicians) say that's true; the oils do mix.
I have never seen conclusive evidence of oil mixing on a properly bled and well maintained cartridge and I remain on the fence.
If you run standard fork oil in the damper leg and run low friction motor oil in the air spring leg, you'll get the benefits without risk of mixing those oils.
@skyrebel88
I would guess that the seal modification Mark from REP was talking about is simply changing out the garter spring or modifying the rubber to reduce the force increase at higher air pressures. The seal is in the negative chamber, so the highest friction should be at the top of the stroke (hypothetically). I was interested in that and in the discussion on fork lug stiffness...
Mark mentioned some KYB kits were now available without needing the Technical Touch lugs. Made me think of the kits you’ve shown. Are there others? It wasn't clear to me if he was referring to riders preferring KYB kits with factory WP lugs, or any kit (6500 or CVs being the others) being preferred with factory lugs.
I am still not that disappointed with my air forks, but the lure of trying a kit is strong. What I really need are loaner 6500s and KYBs to try out.
I think I have the only true drop-in kit for the WP air forks.
I haven't seen the Ride Engineering kit in person, but it appears they require that you drill out the fork lug and I don't think they include an oil-lock system (hydraulic bottoming cup).
My understanding from that podcast was that the OE KTM lugs are more comfortable than the billet lugs for any cartridge.
Keefer has stated in the past that converting the KTMs to KYB doesn't automatically make them as comfortable as a Yamaha.
I don't get that feeling, but I haven't tested KYB tubes or billet lugs back to back with the OE WP tubes and lugs.
All the feedback I've ever heard is that KYB has the most comfort and front wheel feel.
That's my impression too and why I started doing the conversion kits (originally for my buddies).
I haven't ridden a set of 6500 converted production forks.
I have ridden cone valves, Ohlins and some tuned up AER-48 and XACT 48 air forks as well as Showa A-kit on the 19-22 chassis.
I also have a set of WP forks with KYB PSF-1 cartridges in them here currently.
Those belong to a Beck's Tech in FL, (a RaceTech service center).
We both wanted to experiment with the old KYB low pressure air forks, so I modified some parts and he built them up to test, then shipped them to my shop. I have done a few laps on my 2023 GasGas with them and they aren't terrible. I plan to re-valve those PSF-1 cartridges and see what I can learn before I ship them back.
Was it alot of work to fit the psf1 carrtrige in the wp fork? Did you use your kit also ?
Starting with an old prototype version of my conversion kit, I chopped off the oil lock cup.
The rebound adjuster in my kit works as delivered since the KYB part is the same between AOS / SSS spring forks and the PSF-1 forks.
We used a Honda cartridge which is very short. The Kawasaki parts are longer.
Also, the upper aluminum "cap" portion of the PSF-1 cartridge needed a modification to thread into a WP fork tube.
I have been too busy in the shop to get into those cartridges and play with valving.
Pit Row
Have you had any experience with the dal soggio inserts? Or possibly the XR kit they make for the kyb's?
I haven't ridden anything from Dal Soggio, but I have read positive reviews about their stuff.
The standard KYB pistons have worked so well with just shim changes that I continue to stick with revalved production YZ and KX cartridges in my own bikes. When I get the opportunity to try something different or new, I always take it in case there's something to learn.
I'm just a home tinkerer, so far from an expert. I've had dal soggio's and ohlins on previous ktm's, 22 and prior, and kyb on my 23 so never really got to test them back to back.
My kyb's on my 23 350sxf were awesome and I've been using similar settings for the kybs on my TF450 and stark with good results. I got given a good setting from a suspension shop for racetech base valves but have been messy around with my own settings and ideas on the midvalve. Mainly trying to see if I can get the standard trampoline mid to feel more like a traditional spring float mid.
I like the feel of a leaf spring mid valve if the base valve is tuned to match.
If you want the conventional style float, you can get the springs from an older KYB Yamaha application and switch out the leaf spring shims for a couple of thick stopper shims to set your float number. Some off road guys do that and some tuners prefer that type of setup.
I have been using the traditional style float setup mostly and found a good setting but more recently switched to the leaf style. My first try I just used the same mid valve stack as before but with a very light leaf setting and seems to feel very good. Need to test it on some rougher tracks but. I like the the idea of the leaf setup but it's just more things to learn, lucky like tinkering ha ha.
Post a reply to: WP AER 48 air fork users, help/opinion wanted