MikeInOhio
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I only dive with Poseidon gear. The only problem is getting the reg serviced....
Regulator
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I dive with as many different brands as possible and service all my own kit.
Zeagle 6 1st stage, Kirby Morgan primary, Apeks back-up and Dacor brass gauge.
OMS plate, Halcyon STA and cam bands, Oxycheq wing.
Zeagle 6 1st stage, Kirby Morgan primary, Apeks back-up and Dacor brass gauge.
OMS plate, Halcyon STA and cam bands, Oxycheq wing.
Send it to me; I'm a certified Poseidon tech!
Hey Tfsails,
How well would a Cyklon 300 second stage work with a first stage like a MK 10 with 135 psi ip? I know the Poseidon is designed to work with much higher, but just curious.
thanks,
couv
How well would a Cyklon 300 second stage work with a first stage like a MK 10 with 135 psi ip? I know the Poseidon is designed to work with much higher, but just curious.
thanks,
couv
The Cyklon 300 was my favorite regulator back in the 70’s, the second stage is still my favorite second stage, even tough the Scubapro 109 is far more practical and may even perform better. The unique hose in the Cyklon is inconvenient and the adjustable spring tension in the 109 makes it a great alternate second, etc.
I still always like the side exhaust of the Cyklon and the universal left or right, no up or down position.
For the Cyklon second stage to perform well it does need a high IP. The actual adjustment process for the Cyklon involved raising the IP (with low tank pressure, since the unbalanced diaphragm first stage) until the second stage leaked and backing it of some.
I was never too impressed with the Cyklon first stage; I didn’t like the unbalanced diaphragm design and didn’t like the soft orifice with hard cone sealing valve.
I still have three Cyklon regulators and in my “to do” list is to try and modify the second stages so they can perform well with the lower IP used by most other regulators.
My preferred first stage is a Aqua Lung Conshelf or Titan, which does have an easily adjustable IP, but I would like all my regulators to run at a standard 135 to 145 psi.
My thought is to try and find a slightly different spring for the demand valve. I have heard it has being done, but they could not tell me were they got the spring or how I could locate the exact same spring. If anyone else has done it I would like to know.
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Thanks Luis,
My curiosity about the Cyklon 300 goes back to the '70ies too. The dive shop where I took my lessons sold them and my instructor told me it was the best regulator in the world. I was only 19 at the time and those words coupled with the fact that it is still the best looking second stage ever built weighs on me even today. The side exhaust and the no left/right- up/down add to it's overall attractiveness. In a way, I am happy to hear they do not perform well when coupled with a first stage with a lower IP. Knowing that helps to keep me from buying yet another regulator I do not need; but then again....
c
My curiosity about the Cyklon 300 goes back to the '70ies too. The dive shop where I took my lessons sold them and my instructor told me it was the best regulator in the world. I was only 19 at the time and those words coupled with the fact that it is still the best looking second stage ever built weighs on me even today. The side exhaust and the no left/right- up/down add to it's overall attractiveness. In a way, I am happy to hear they do not perform well when coupled with a first stage with a lower IP. Knowing that helps to keep me from buying yet another regulator I do not need; but then again....
c
When I have some time I will work on modifying the Cyklon second stages to get it to work with lower IP. I would really like to use it with some of my environmentally sealed Conshelf first stages.
I agree that it is the best looking second stage…and you don’t get that hubcap in your mouth look.
But that second stage has many other advantages:
• It is light weight and it does feel light in or out of the water.
• It has all the advantages of a metal second stage, but with the semi-soft plastic exhaust shroud. You never harm or scratch the metal case when you drop it or bang it on a tank.
• It is a very simple down stream demand valve, but with a clever compound linkage that for the most part, avoids linear sliding friction…there are just some pivot points.
• The exhaust is concentric with the demand valve diaphragm, basically avoiding the so called “case fault geometry”. It is not prefect due to the large diameter of the exhaust membrane valve, but in practice it works very well.
• The case can be opened with no tools to inspect the linkage, the outside of the demand valve, etc.
• The bubbles to one side only are less annoying.
• The performance of this second stage can be outstanding. It has a very effective venturi assist, with the demand valve almost between you lips.
• Very low profile main body.
The only issues with this second stage are:
• It requires a high IP. This is a show stopper if one wants to use it with other first stages, but I hope to work on solving that.
• The odd size hose connection. This can be a somewhat of an issue, but there are adapter for the first stage ends of the hose.
• The diaphragm assembly unscrews very easily with no tools from the main body and accessing the exhaust valve is also easy, but removing and particularly replacing the diaphragm is a royal pain. There is a special press used to install the diaphragm. I actually own one of this presses and I even had to modify its use to make it work. The good news is that it is very rare that one need to remove and reinstall the diaphragm from its sub-assembly.
• One more odd thing is the size of the mouthpiece, but that is not a big deal…I just stretch any mouthpiece to fit and it is OK.
After writing this stuff, I am thinking that I need to make some time and work on those second stages.
I agree that it is the best looking second stage…and you don’t get that hubcap in your mouth look.
But that second stage has many other advantages:
• It is light weight and it does feel light in or out of the water.
• It has all the advantages of a metal second stage, but with the semi-soft plastic exhaust shroud. You never harm or scratch the metal case when you drop it or bang it on a tank.
• It is a very simple down stream demand valve, but with a clever compound linkage that for the most part, avoids linear sliding friction…there are just some pivot points.
• The exhaust is concentric with the demand valve diaphragm, basically avoiding the so called “case fault geometry”. It is not prefect due to the large diameter of the exhaust membrane valve, but in practice it works very well.
• The case can be opened with no tools to inspect the linkage, the outside of the demand valve, etc.
• The bubbles to one side only are less annoying.
• The performance of this second stage can be outstanding. It has a very effective venturi assist, with the demand valve almost between you lips.
• Very low profile main body.
The only issues with this second stage are:
• It requires a high IP. This is a show stopper if one wants to use it with other first stages, but I hope to work on solving that.
• The odd size hose connection. This can be a somewhat of an issue, but there are adapter for the first stage ends of the hose.
• The diaphragm assembly unscrews very easily with no tools from the main body and accessing the exhaust valve is also easy, but removing and particularly replacing the diaphragm is a royal pain. There is a special press used to install the diaphragm. I actually own one of this presses and I even had to modify its use to make it work. The good news is that it is very rare that one need to remove and reinstall the diaphragm from its sub-assembly.
• One more odd thing is the size of the mouthpiece, but that is not a big deal…I just stretch any mouthpiece to fit and it is OK.
After writing this stuff, I am thinking that I need to make some time and work on those second stages.
widget
Contributor
Yes, I think that was probably true at the time, most of us diving at that time cut our teeth on Poseidon and usually the 300, in its day it was state of the art and certainly the best reg available.
Unfortunately, in my opinion, Poseidon fell off the bus in the 90s and most of the other manufacturers caught up and passed them, quality and breatheability wise and I dont think they have ever managed to catch up.
The Triton was a disaster and gave endless problems until it was canned, and the cyclone has really undergone limited (if any) meaningfull changes since the 70s, and even the Jetstream and X treme struggle in the face of modern day reg competition.
..........but I still have my old 300 in my cupboard, although I have often considered just using it as a shower head,
it has its sentimental value.Couv--
The Cyklon second stage will probably work ok with any first stage that puts out 135psi as its IP. The unbalanced Cyklon first stages put out about that IP with 3000psi input, but their IP goes UP when input pressure is lowered, to about 175psi with 300 psi input. This is one of the few first stages where IP goes up as input pressure goes down. Most unbalanced firsts do the opposite--IP goes down as input pressure goes down.
A Cyklon second stage gets easier to breathe as the IP goes up, just like any other downstream regulator would. To me, the myth that second stages must be mated to a first stage of the same brand is just that--a myth. How does the second stage know where the IP input is coming from? It doesen't--it's just a dumb piece of plastic or metal. Go for it!
TF
The Cyklon second stage will probably work ok with any first stage that puts out 135psi as its IP. The unbalanced Cyklon first stages put out about that IP with 3000psi input, but their IP goes UP when input pressure is lowered, to about 175psi with 300 psi input. This is one of the few first stages where IP goes up as input pressure goes down. Most unbalanced firsts do the opposite--IP goes down as input pressure goes down.
A Cyklon second stage gets easier to breathe as the IP goes up, just like any other downstream regulator would. To me, the myth that second stages must be mated to a first stage of the same brand is just that--a myth. How does the second stage know where the IP input is coming from? It doesen't--it's just a dumb piece of plastic or metal. Go for it!
TF
I used to service the Cyklon 300 back in the 70's, but I don't remember the IP with a full tank (that was 2500 psi back then for us). I have looked in a couple of manuals, but can't find it either. I may have to check some of my old first stages, but I haven't serviced them in over 30 years.
Are you sure the IP will swing that much? A 40 psi swing seems like a large pressure swing (from 175 psi to 135 psi), but I guess it is very possible. I never thought the Cyklon 300 first stage was the greatest.
The second stage will definitely work with lower IP, but like any basic down stream valve, the closer the IP and the spring force are balanced the better the performance.
I need to get back to playing with this regulators.
Are you sure the IP will swing that much? A 40 psi swing seems like a large pressure swing (from 175 psi to 135 psi), but I guess it is very possible. I never thought the Cyklon 300 first stage was the greatest.
The second stage will definitely work with lower IP, but like any basic down stream valve, the closer the IP and the spring force are balanced the better the performance.
I need to get back to playing with this regulators.
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