17 KTM air fork problems

[Snowbike241]

Ran my air fork the first year I got my bike and blew the air past the chamber to the half stroke(normal 17’ problems every air fork had).Took it in to the dealership and they replaced the seals, grease and haven’t had any problems since. So it’s been two seasons on snow and two seasons on dirt. Ran it this year and it happened again. Tore the air chamber fork apart and bled the air out, put it back together added oil and was back in business. Next day the fork would go to half stroke like it did it again. But this time We would stand on the ski and pull it up and it was normal... I’m confused on what’s going on? When the air on left side fork (air side) goes out of the chamber you can’t pull it up like that. But when this happened that day I still had 200psi and I was able to reset the fork height by pulling it up.. is it my left side fork(oil side) that is creating a vacuum?? And sucking it down? I haven’t replaced any seals and did noticed oil in the snow? Had anyone had this problem? Thanks

 

[hankohlson]

Did you upgrade to the 18+ air chamber piston and seal?

 

[Snowbike241]

Thanks for the reply. I didn’t upgrade the piston. Did the seals after the first blow out. Never read about the piston needing changed?

 

[hankohlson]

The 18+ seal upgrade is a big change and requires a different piston. It's a lip seal design and the more air pressure the better it seals. I haven't heard of failures with this upgrade. I would guess if you were able to lift it back up after the failure the seal is either damaged or compromised. I'm on a 17 450SXF and replaced the seal myself but its a job. Here are some pics of both seals.

 

[Snowbike241]

Wow thanks! Where did you get the parts? Are you running a air-pro, mud scrapers, anything special that also helps? It’s crazy that I ran two seasons hard with no issues until now. Makes me want to upgrade to springs.

 

[hankohlson]

Parts are all KTM OEM. I'm running the Air chamber seal upgrade, 15wt fluid, Trio, and seal savers. So far so good. After talking to KREFT and Brockstar the 18+ upgrade is the solution.