Air in my shocks - what am I doing wrong

[Loheswaran]

I am wondering whether or not I have lost my building skills and become a complete idiot.

I use a shock pump when building my shocks.

I then use the grub screw at the shock cap end to let oil blead out to set my rebound.

Once set - when extended the shock retracts - giving a type of negative rebound.

so I undo the grub screw in the cap - extend the shock - fine.

the problem is that they now make the familiar noise of their now being air in the shock.

I never had this problem with bladdered shocks - what's going wrong?

[luniemiester]

One thing I have found with the shocks is to always refit the shock spring bottom and seat the retaining rubber (just like u would if a spring was fitted) but without the spring. Then fill shock and move shaft up and down to release any air and wait until its clear if bubbles then top up the shock until the oil domes then screw the cap in fully

Then take the bleed screw out and keeping the shock upright push the shaft slowly up allowing oil to bleed freely from the cap until your about 2-3mm from the rubber stop on the shaft meeting the shock. Then get the screw ready by the hole and push the last of oil out and quicky fit the screw. They should be right then

Reason for doing it this way is that this the rubber boot and the cap actually limit the shock so this way helps match the volume of oil based on the stroke of the shaft. This should fix your problem

[mattr]

so I undo the grub screw in the cap - extend the shock - fine.

what's going wrong?
You are actually putting air in the shock...... I usually don't push the shock up all the way, just leave a couple of mm clear.
Then I get a tiny bit of suck down at full extension, and a tiny bit of rebound at the other end of the stroke.
The physics of the shock doesn't allow a perfect set up due to the volume of the shaft and the lack of a bladder, just get as close as you can (without sticking air in)

[Allan1875]

As above never extend the shaft with the bleeder screw out.

We all do it slightly differently. I do it like the other guys but I push the shaft up until the limiter meets the body.

I then put bleeder screw in, pump the shock a bit then repeat the process one more time. I've done this since watching a team associated youtube video as I was always unsure how to do it properly.

[Chalkie]

When you bleed them your meant to leave a 4mm gap when you push the shock shaft in, about the same as the spring seat and bump stop. Also being emulsion shocks they will have air in the anyway it's how they're meant to be and will work fine on the track.

[ekt]

TDs shock build guide to add to the information the others have posted http://www.team-durango.com/blog/2010/07/29/shock-build-guide/

[Chalkie]

TDs shock build guide to add to the information the others have posted http://www.team-durango.com/blog/2010/07/29/shock-build-guide/

Just to add that whilst that guide shows the small bore shocks the big bore shocks bleed exactly the same :)