Reversible/Left-Handed Second Stage for Sidemount

[lexvil]

G260 and D420 can both be reversed

 

[tursiops]

You can get a similar benefit by putting your short hose (left tank) on a 90 elbow. It also cleans up the routing, makes the short hose sit closer to your head.

TBH I’ve never seen anyone use a left hand 2nd stage in SM in the MX cave community, but maybe people do things differently in other parts of the world.

LOL. I've used it in MX. So I guess you haven't seen everybody.

 

[Mobulai]

G260 and D420 can both be reversed

Carrying the torch for the g250, and the D400-350-300/Air1/Pilot
So do all the „modern“ SP ones (R series, S series…); not sure about the C series tho and its single hinged lever

 

[rx7diver]

Sidemount diving was invented by the UK Cave Diving Group members and Poseidon regulators have been the de facto standard sidemount regulator in the CDG for about 40 years at least. Particularly the Cyklone. A lot of members use other regs now but the Cyklone is still pretty much the Land Rover of the CDG for sump diving in harsh conditions.

If I remember right the Odin is the Jetstream over here? I used them for a couple of years for SM but found them a bit sensitive for being dragged through crap. but yeah, sidemount diving is the only time I still use my Poseidon regs. I think my preference will always be the Cyklone though.

Yes, the instructor for my Cavern and Basic Cave certs (NSS-CDS/NACD, in 1989, in FL) used Cyklons, my first time ever hearing of and/or seeing Poseidon regs. IIRC, he preferred them because the very simple second stages could be disassembled U/W without tools, to clean out debris. I liked the look of his, because side exhaust and, especially, shiny!! Very high intermediate pressure, though, I think.

rx7diver

 

[halocline]

Carrying the torch for the g250, and the D400-350-300/Air1/Pilot
So do all the „modern“ SP ones (R series, S series…); not sure about the C series tho and its single hinged lever

Just to be clear, the original D series (D300-350-400) is not reversible. Air 1 and pilot are. G250, no.

 

[tbone1004]

Hi all, I was thinking of purchasing the Deep6 Signature Sidemount set, but then I realized that the second stage is not reversible/capable of being placed in a Left-Handed configuration. I'm therefore wondering: For people who have experience diving sidemount both with and without a reversible second stage, how beneficial is having the reversible second stage?

If it is really beneficial, then I was thinking of perhaps going with a Deep6 Signature for one regulator and a reversible regulator like the Apeks XTX50 or Diverite XT1/XT2 for the other. Alternatively, could I use an Apeks XTX50 or Diverite XT2 second stage with a Deep6 Signature primary stage? Thanks in advance for your comments! Of note, I will be diving with a 7 ft long hose on my right tank and a short hose on the left tank.

fitting thread since this memory came up of one of my friends trying out my sidemount rig. Pardon the tank trim, a. this was 2010, b. I'm 6'3" and she's 5'2" so my rig was swimming on her, but you can clearly see the reversed Apeks XTX50. We were also very early in the days of commercial sidemount so there were no books on anything, the only youtube videos we had were the super early Steve Bogaerts videos, it was the wild west back then! Learn from our trial and error and be grateful it's mostly standardized now!

Now, why to bring this up. 15 years ago I started using a reversed long hose on my right tank because it kept the hose held up on the back of my neck and wasn't a snag hazard, so all sorts of wonderful justifications for doing it. The deal-breaker comes when you actually have to donate that hose. When you donate that long hose the hose now has to cross which not only removes effective length, thanks Pythagoras! which makes a single file air share much less comfortable, but in doing so it also puts a lot of rotational torque on the mouthpiece which makes it less comfortable to hold by the OOA diver and also more prone to snagging on something if you're coming out of an air share.
An alternative would be to have a lefty reg on the left tank but then you come into an exact hose length problem which is surprisingly uncomfortable to dive.

How do we solve this? Most people in the world just dive what has become the defacto standard for sidemount regulators and have their long hose on their right and it does a hog-loop just like it would in backmount. It's not a real large concern in super tight passages and it's quite easy to contend with in general.
What I personally do is use Poseidon Jetstreams and cross the long hose from the right behind my head like in the picture above, but I do a modified air share technique. Where you normally rotate the second stage on the vertical axis which protects the diaphragm orientation, I rotate mine on the horizontal axis and it goes from "upside down" in my mouth to "right side up" in the OOA divers mouth. This maintains the straight hose coming up the right side of both divers.
Now, why do I do that and should you? I do it because I actually like the way the Poseidons breathe and frankly only do it "because I can" with those specific regulators. I do think it is better when you have those regulators, but you have to decide on whether or not those regulators are ideal for you. Most people actually don't like the way they breathe, and one of my good friends and dive buddies has said he'd rather drown than breathe on a Jetstream for a 2 hour exit, and I'm pretty certain he might actually try.... They are completely different than anything else on the market and unless you decide that you like them, it could be an expensive way to find out you don't. I'm a huge proponent of the Deep6 regulators and use them almost exclusively, even as first stages with those Jetstreams, and certainly believe that most people should at least start with what is "standard" and learn what the box is before they try to step outside of it.

 

[Mobulai]

Just to be clear, the original D series (D300-350-400) is not reversible. Air 1 and pilot are. G250, no.

Oops my mistake about that — I always thought the metal blanking „button“ on the D series side was for flipping the „barrel“, I’m yet to fully disassembled one (but did the Air1 and Pilot so I built my assumption from there)