FX Cyclone Problems.

[Troubledshooter]

The valve pin on mine appears to be fine.

[SuffolkRifle]

Are you getting a 'thud' when the hammer hits the valve pin?
Is any air released on a 'dry fire'?

[Troubledshooter]

Are you getting a 'thud' when the hammer hits the valve pin?
Is any air released on a 'dry fire'?

Yes, a slight thud when the hammer hits the valve pin, but no air is released.

[SuffolkRifle]

Horrible thought is that the valve is stuck, if the valve pin is ok, it's the only thing left

[Strimmer]

Any luck in getting it sorted? Don't like to see a cyclone down

[Troubledshooter]

I think I may have found the problem but won't know for sure until I re-assemble it, at which point, if the rifle is performing correctly once more, I will post more info.

[Troubledshooter]

The problem arose because the two barrel securing grub screws were not tight enough, so when a silencer was fitted and tightened, the barrel rotated and the transfer port became unaligned with the action. This didn't become obvious until the rifle was stripped and the two halves of the action separated.
I spoke to Ben Taylor about this and he was under the impression there should be a third grub screw to prevent the brass transfer section of the barrel from moving once aligned with the action and power adjuster, which is what I would have expected, but there isn't, and I can find no mention of this third grub screw in the official FX Cyclone exploded diagram and parts list, only the two barrel securing grub screws.