Originally posted by Hotsauce
.... Has the reason for failure on our shocks been determined? can anything be done to improve prevent our failure mode?

I only left one shock with Bruce so he could only provide insight on why that one shock failed. (I'll have him look at the others when I pick my forks up) He thinks dirt probably killed it. All it takes is a few grains getting past the wiper and lodging between the seal and shaft and you have a leak. This particular shock had about a tablespoon of sand crammed in the area under the Schrader valve cover. No idea how it got in there but I saw it with my own eyes. That had nothing to do with leakage but the point is dirt gets into everything.

These shocks are under high pressure so once they start to leak they're going to leak fast so you need to keep an eye on them. Isuzu opted to make handling/performace a priority which resulted in a shock configuration that is more likely to leak. They reduced unsprung weight by mounting the lighter shaft to the control arm and the heavier shock body to the frame - which places the seal at the bottom of the shock. So when it starts to leak, the drain, so to speak, is at the bottom and it will leak until dry - unlike other shocks (with seal at top) that will leak profusely only until the floating piston that separates oil from nitrogen bottoms out. (Or was it tops out?)

Speaking of floating pistons he said this is the first Japanese reservoir shock he's seen that uses a floating piston rather than a bladder. It's designed like a European shock (e.g., Ohlins, White Power, Marzocchi) and is a little more expensive to rebuild because the piston is a PITA to work with. On Skidplate's shock, some fluid had actually leaked past the piston and gotten into nitrogen territory for some reason.

Can anything be done to prevent premature failure? Yes and no. He said if you guys will clean these things every now and then they might last longer. After a day in the dirt, just loosen the band clamps, drop the boot and blow the grit out with compressed air. Be careful not to force dirt into the seal though - keep the airflow perpendcular to the shaft. On the other hand, this is a high performance type shock - with 200 psi charge, mounted upside down, with damping stiffer than Ron Jeremy. It was built to perform - not built to last. And there's not a damn thing you can do about that except properly maintain your KYB or replace it with a conventional, less performance oriented (and cheaper!) shock. And by maintain he meant have them rebuilt before they leak dry and trash themselves. You guys with bikes know what it's all about right?