Originally Posted by Airhead Wrangler
Mine are particularly bad, but that's just because I bought them used on ebay and put them straight on my bike without even changing the oil. They clearly are in need of a full rebuild. That said, the other 4860s I've seen have more stiction than conventional forks, but I don't really notice much when riding them. The improvement in stiffness and overall function is so much better (on forks in good condition) that I don't really care about a bit of stiction when fully extended.
Proper setup is king. I've had lot's of WP USD forks on various bikes, probably six or seven pair. I've seen them mushy and and like a jack hammer. Always a challenge to get dialed. One of the nicest sets was a pair of 43's that started out way under-dampened on rebound. Rather than re-valving, I tried 10w oil and cranked the top clickers down to like three notches from all the way in. Worked like a dream on my heavy-ish KLX650. The thing never packed down. Go figure.
By contrast the 48's on my KTM690 are still way too harsh and stick like crazy even after being re-valved and sprung by one of the best guys in town. They are much better than before the work, but still harsh. Go figure again. The ones on my first 450exc were always excellent. Light bike = less challenge, I guess.
The HPN/WP 38mm variation on my old PD were downright horrible. Not sticky but flexed like mad and were way too soft. Never really set-up correctly because I bought the bike with them installed, parts were weird, and I didn't want to mess about and break stuff.
The other huge variable is weight balance and rear shock. If the bike isn't centered, no amount a fiddling will result in a stable situation. Front too high, forget about it. Sometimes that's tough to figure out, specially if the rear shock is too soft, or under dampened. The rear squats or pogos, and it feels like the fork is out of whack. Many times, not so. The forces are translating. I'm no expert but even good hardware sucks if it's not well dialed.
I just don't think you can properly judge a fork until every effort has been made to get it right! Certainly don't assume that because a buddy can't get his sorted that it is the fork's fault. It's hard to know, what the potential is. That's my 2 cents. The 43's going on this new bike will be made right even if I have to redo them five times.