G'day folks,
I like the idea of restricting the vacuum supply to the decompressor better than trying to restrict air flow to the other side of the diaphram which gets mixed up with the compression gases.
Yep, +1 on that.
I have never taken much notice of these decompressors. Always OK and left alone. the restrictor is in the end where the tube goes on I suppose.
There's a pic of the later type black decomp nozzle, with the restrictor, over in my decompressor rebuild thread [see the 'stickies' at the top of this forum section].
Dunno about other sources, but the ODK shop has these in stock; link is in the first post of that thread.