2014 Trek Fuel EX-8 Fork problem

I'm going to start working with the rear as well. I'm 200 lbs geared up. I'm pretty sure mine has a higher adjustment range on the rebound. I'll count total clicks. Yes, I do wait for that second chamber to show up on the pressure gauge when I'm adding air to the shock. I'm glad this is working out, I was starting to doubt my bike purchase!

 

You don't really wait for the second chamber. You pump the shock up to the desired pressure, then cycle the shock to 50% of travel to pressurize the second chamber, and then pump it back up again.

 

Thanks, I didn't know that. I'll give that a shot tonight before we ride Whiting.

 

Yep. Do the same in decreasing pressure. Compressing the shock opens up the drcv valve and equalizes the chambers. When you don't compress it to 50%, the chamber equalizes on the trail and it will be substantially higher or lower than what u want.

 

Thought the DRCV stuff had special air valves, where you had to thread the shock pump fully onto the valve, rather than "whenever" after you get a pressure reading on the gauge.

Also, beware that if you set sag with the shock pump still attached, it's not the same as setting sag with it removed, unless you have a shock pump like the Topeak DXG in which you can unthread it (retracting the bit that depresses the valve) to close off the shock/fork's valve, without totally removing the pump. This is because the air hose acts as a volume extension, and a higher volume air spring will behave differently than one with less volume (at the same PSI).

Though, if you know exactly how much PSI you want to put in, and want to cycle the fork/shock a bit to equalize other chambers, you can leave it on. The volume extension doesn't affect how much psi is actually in the fork and shock, unless you lose a bit of air out of the valve, though much of that air release is from the shock pump's hose, since pressure within the fork/shock should close the valve shut, once the pressure from the hose is lessened.

 

It's all here http://www.ridefox.com/fox_tech_cen...stprod/content/forxtopics/2012_drcv_trek.html

 

First, the drcv shock has two chambers. The air input valve is just that. It's an ordinary air valve, no matter how fancy they call it. Inside there is a plunger valve. When the shock compresses past 50-60% the shock body actuates the plunger, and opens up the air valve, combining both chambers into one.

When you pump up the shock, your pumping chamber 1. When you compress the shock, chamber 1 pressure ramps up, then at 60%, chamber 2 opens up and is pressurized at that compressed state. Chamber 2 will always have higher pressure than chamber 1. You see the problem here when you are decreasing pressure? Chamber 2 can bring up the pressure of chamber 1 when cycled. So it's important to cycle the shock when adjusting pressure to get a good idea of what pressure you're actually running. Same goes for increasing pressure, but ime, to a lesser extent.

As for spiking, when you cycle the shock, both chambers are at equal pressure at that point of shock stroke. What happens is that when the plunger valve opens, the character of the shock goes from small volume to large volume, a subtle change. I've never felt spiking with the drcv, can't speak for the fork.

lotsa people complain about the rp shock, I find that on a well designed trail bike, it gets the job done. Cant complain. But then. I'm 165 and I do know that over 200, the shock struggles.

there are reports that the db inline and the db air is having the same weight rebound issues for riders over 200 pounds. Db air cs seems to be doing better on that regard.