Ahem, hypothetically speaking, if I had been a clot and not read the manual properly and put 15ml rather than 10ml of oil into the both lowers of my reba fork, would that cause a loss of almost half the travel followed by a firm stop and a clunk?

Hypothetically you understand…

No, hypothetically it wouldn't.

nope. It would take a lot of oil to do that – like perhaps all the oil from the damper leaking into the lower leg

B*gger, thought I might be on to something with that. All I did was remove and clean the air spring, remove the spacer, replace the oil and refill the lowers. Now when compressed the fork seems to come to a firm stop too early. Any other ideas?

this fork has a damper cartridge in the top of one leg does it not? Has the oil from that gone into the lowers – that could cause hydraulic lock.

Could be as simple as a displaced o ring causing that

Take 'em apart and check

Thanks for the advice, I think taking them apart to investigate is the way ahead. Hopefullyit won't be too much hassle!

Sounds like the damping oil in the top if the left leg has leaked out into the lower leg. It's a common RS problem fixed with 2 new O rings on the damper shaft guidein the bottom of the stanchion

To check, drop the lowers and see if there's a lot of oil in the left leg, when there should only be 15ml

Thanks for the advice, I think taking them apart to investigate is the way ahead. Hopefullyit won't be too much hassle!

5 ml extra probably wouldn't but, say, putting 30ml on top of the existing of 15ml would hypothetically cause what you're talking about subsequently (hypothetically) causing the wipers to pop out and shower your garage in a fine mist of hypothetical shock oil.