What is the quietest DPV?

[Superlyte27]

I'm not going to say "no". When/where do you want to hit it?

Next weekend? Ginnie?
You got CCR to use or do I bring one of those too?

 

[sunnyboy]

Pete, I know you didn't state this as a factor in your question, but since you live near cave country, you can probably buy an almost perfect condition Gavin for a fraction of what any other scooter would cost.

Other than the weight of the SLA batteries being a factor, the Gavin probably is the quietest scooter you're going to find these days.

 

[The Chairman]

Pete, I know you didn't state this as a factor in your question, but since you live near cave country, you can probably buy an almost perfect condition Gavin for a fraction of what any other scooter would cost.

The biggest "oops" I have ever seen was a guy riding a Gavin. It was so dramatic, it caused me to miss a jump in Ginnie. I'm sure it was all operator error, but I was coming to the end of the Bone room line and while I heard him, his light coming at me surprised me just as me being in his light surprised him. He let off the juice and crashed into the ceiling. Wow. I was totally underwhelmed by that experience. I know I never want to make that mistake!!!

FWIW, before I buy any scooter, I want to know

• Do I really want one?
  • There is no need!
• Are they even worth it?
  • Added Complexity
  • Noise
  • Toting back and forth
• Noise levels
• Power
• Ease of Use
• Other Pros
• Other Cons
• WHICH ONE FITS ME BEST???

 

[tbone1004]

@The Chairman

• Do I really want one?
  • Yes, yes you do really want one. Not kicking is amazing
• Are they even worth it?
  • Added Complexity
    • Not that complex. Adds complexity to your dive planning, but you are already diving a CCR, so it doesn't actually change your dive planning. If you get to a point where you don't want it, just leave it on the line *in an appropriate spot that won't cause problems on the floor*
  • Noise
    • can't help you there
  • Toting back and forth
    • that blows, but make friends with MAG and steal his design for toting his UV26 around. It's great for pretty much everywhere except LR where everything sucks
• Noise levels
  • Largely a function of motor speed. So anything without a speed controller is going to be louder than one with
• Power
  • Anything that is a gavin or better is going to have sufficient power. May not move you that fast, but it's not always about speed
• Ease of Use
  • They're all easy
• Other Pros
  • no kicking is amazing and I find I actually see more of the cave, especially in high flow caves, when I can use a scooter. I put my UV or viper on low and don't have to worry about cutting the cave properly to avoid the flow. Means I can look around and see everything. It's properly amazing
• Other Cons
  • They're expensive and can be heavy
• WHICH ONE FITS ME BEST???
  • it's like choosing a rebreather. They're all going to do a damn good job, but based on who your buddies use, which ones you get a good deal on, and how the service works is going to sway you one way or the other

​

 

[sunnyboy]

The biggest "oops" I have ever seen was a guy riding a Gavin. It was so dramatic, it caused me to miss a jump in Ginnie. I'm sure it was all operator error, but I was coming to the end of the Bone room line and while I heard him, his light coming at me surprised me just as me being in his light surprised him. He let off the juice and crashed into the ceiling. Wow. I was totally underwhelmed by that experience. I know I never want to make that mistake!!!

FWIW, before I buy any scooter, I want to know

• Do I really want one?
  • There is no need!
• Are they even worth it?
  • Added Complexity
  • Noise
  • Toting back and forth
• Noise levels
• Power
• Ease of Use
• Other Pros
• Other Cons
• WHICH ONE FITS ME BEST???

Pete,
You might not like the answer to the last one... it might well be "none".

Of course, not spending money is sometimes a good thing. Especially with SCUBA gear. :-D

 

[Ouvea]

Not to add another card to the deck but has anyone seen this DPV from Seacraft?

Seacraft

I've been next to Suex, Gavin, DiveXtra (Piranha/Sierra/Cuda400), Genesis 1200 and my own Viper. Just my opinion through a 10mm hood, I find the Suex the quietest

 

[DA Aquamaster]

I don't disagree (much) with Tom on general principle as he's intelligent and knows his way around dive equipment. But some of my answers are slightly different (mine are in red):

• Do I really want one?
  • Yes, yes you do really want one. Not kicking is amazing
• Are they even worth it?
  • Added Complexity
    • Not that complex. Adds complexity to your dive planning, but you are already diving a CCR, so it doesn't actually change your dive planning. If you get to a point where you don't want it, just leave it on the line *in an appropriate spot that won't cause problems on the floor*
    • I mostly agree but, dive planning, and in particular gas planning to cover a failed DPV contingency is a HUGE part of Cave DPV on open circuit. I recommend a Cave DPV class and I recommend you do it open circuit, since that's what you'll be doing if you have to bail out on CCR. For CCR it is arguably less of an item since you'll still be fat on gas if the DPV fails, and if the CCR also fails in a manner that puts you completely off the loop, some may argue that it just ain't your day. But, you still need to consider the potential increase in decompression obligation if your DPV fails and you have to swim out. A Cave DPV class will cover DPV related contingencies, such as towing out a team mate with a failed DPV, carrying a back up DPV, etc.
    • There is also a need to learn how to properly park a DPV in a cave. I see this badly done so often that I wonder what percentage of divers with DPVs in a cave actually have a Cave DPV cert. I also see so many cowl marks in the floor in places where scooters should not be used that I wonder the same thing, and if so, wonder how an instructor could fail so miserably with his or her students. Sometimes it's just the little details that bother me, such as not tying a DPV off so that it is facing out of the cave. It makes things so much easier on the way out and it eliminates any doubt which way is out which helps prevent your team mate from blasting off in the wrong direction.
  • Noise
    • can't help you there
  • Toting back and forth
• that blows, but make friends with MAG and steal his design for toting his UV26 around. It's great for pretty much everywhere except LR where everything sucks
• Size matters, and size has gotten better with battery technology. With lithium batteries you can get a 25 pound DPV that will pull you in technical dive configuration at over 200 fpm for about 50 minutes or pull you in the same configuration at 150 fpm for 150 minutes, and for another 10 pounds of weight you can double that.
• It's great to be able to walk out of the water with your DPV in one hand.
• Noise levels
  • Largely a function of motor speed. So anything without a speed controller is going to be louder than one with
  • Just my opinion but noise seems to go up in this order: 1) Direct drive, 2) belt drive, 3) helical cut gear drive and 4) non helical cut gear drive.
  • DPVs that use the Oceanic style motor are constant speed (although that speed can be higher or lower based on how the armature in the motor is wound). What changes is the prop pitch. More pitch equals more amps being drawn to maintain the fixed and constant motor rpm. Where I partly disagree with Tom is that the noise does change in frequency and sometimes in overall volume as the prop pitch is increased.
• Power
  • Anything that is a gavin or better is going to have sufficient power. May not move you that fast, but it's not always about speed
  • I would never recommend a scooter with less than 50 pounds of thrust and 60 is a better minimum. Speed wise, 230 fpm is nice, but 150 fpm is usually much more efficient and will give you much better burn times. Drag is a square function - 2 times the speed results in 4 times the drag and in turn requires 4 times the power. The burn time at 150 fpm may be 3 times what you get at a maximum speed of around 230 fpm.
• Ease of Use
  • They're all easy
  • Some are easier than others. Larger scooters cruise really nice, but they are not as maneuverable. Small scooters can be squirrelly and take more effort to drive, so the details in the design matter.
  • For cave use you want a DPV that is neutral, stays neutral and thus stays where you put it when putting in a jump. Yes, DPV Cave divers should still be on continuous line.
• Other Pros
  • no kicking is amazing and I find I actually see more of the cave, especially in high flow caves, when I can use a scooter. I put my UV or viper on low and don't have to worry about cutting the cave properly to avoid the flow. Means I can look around and see everything. It's properly amazing
  • I agree it's amazing. In addition to using less gas, your CO2 levels will also be lower and since CO2 is very narcotic, lower CO2 means seeing more of the cave and remembering more of what you saw.
• Other Cons
  • They're expensive and can be heavy
  • I think the era of the 90-100 pound DPV is pretty much over. Even 50 pounds is heavy for most casual cave diving purposes and the performance you can get out of a 25 to 35 pound DPV today is amazing.
• WHICH ONE FITS ME BEST???
  • it's like choosing a rebreather. They're all going to do a damn good job, but based on who your buddies use, which ones you get a good deal on, and how the service works is going to sway you one way or the other
  • you definitely should try before you buy.

​

 

[tbone1004]

Not to add another card to the deck but has anyone seen this DPV from Seacraft?

Seacraft

I've been next to Suex, Gavin, DiveXtra (Piranha/Sierra/Cuda400), Genesis 1200 and my own Viper. Just my opinion through a 10mm hood, I find the Suex the quietest

no US repair, only brand I've seen distributing it is a shop that I wouldn't spend a penny with, so yeah not on my list.

@DA Aquamaster

On the Dive planning side, I was assuming no backup scooters, so your cf/100ft of penetration doesn't change. If you do your bailout based on time only then you'll have to equate that to penetration distance. In either instance, you base your cubic footage on exit speed and without a backup dpv, that doesn't change from kicking. Doesn't change needing a good DPV course for all of the dpv specific skills, but I don't think it changes the complexity vs. a CCR. CCR planning for me is more complicated than the DPV planning. I.e. with the DPV I know that my DPV tops out at 200fpm, and I kick about 50fpm, so with my DPV I know that I need 4x the gas to get out as I need to get in, and adjust that to conservatism, so that comes out to about sixths. I know that my buddies DPV goes a lot faster, so we need to be more conservative, but you can still base your exit as a multiple of your entry. On CCR you don't have any entry gas to reference, so the CCR gas planning is more complicated than DPV planning IMO. Unfortunately none of the agencies and instructors seem to have anything better than "you need 2x the gas you need to kick out* and you have to figure out how to calculate that.

bite me on the size of your baby piranha since I have a UV-26.... I'm borrowing one of those for a decent amount of time next time I see you. I agree on the era of those DPV's being over though. They're great first dpv's since they're cheap, but good lord are they heavy

My UV and Viper have speed controllers with 3 RPM settings and there is definitely a difference in noise with the three settings, and speed 1, pitch 9 is a lot quieter than speed 3 pitch 1.

 

[lucca brassi]

GAVIN XLT 95 study News

must be serious thrust ( as seen on subs )

 

[Superlyte27]

Unfortunately none of the agencies and instructors seem to have anything better than "you need 2x the gas you need to kick out* and you have to figure out how to calculate that.

Nonsense.
And dpv bailout and CCR bailout are easily calculated. But I have sat in with MANY instructors who do not do it accurately in my opinion.