Just striped the lowers off my pikes to do a lower service which I have done a few times before. Everything went to plan but when I put the air back (+) first the forks extend but when I put the pump onto the neg there seemed to a bit of air in there but when I pumped it up the forks sucked down from 140 travel to well below 125mm. I striped them down again emptied the oil and started again and the same result. Any ideas what is going on with them?

Cheers.

usually means there is more pressure in the negative?
*maybe, not sure mate sorry

Sounds like the dual air side is leaking. You need to fill the +itve first then the neg, always empty the neg when changing pressures.

If your doing this then time for a dual air service just done my pikes only to have the damper fail 2 days after fixing the air side!

I only serviced the whole forks a few months ago and its strange this problem only occurred after removing the lowers. I will have a look at the air side, thanks.