x650

[liberato]

The reg is performing just fine! There has been no problems since I got it back from service. I have done about 10 dives with it since the service...

It looks like the European guinea...err...beta test has been a success. Scubapro USA now has an X650 repair kit available with the new diaphragm. I still haven't got mine back yet, though. I assume new retail stock will now be available, too.

 

[JustinW]

There was one decent response as to the difference between the two regs s600 and x650. The SRP is the same between the two regs, what is the difference, why does SP make 2 regs the same price? Are the regs built for the same type of diving? What is the difference?

 

[DA Aquamaster]

It looks like the European guinea...err...beta test has been a success. Scubapro USA now has an X650 repair kit available with the new diaphragm. I still haven't got mine back yet, though. I assume new retail stock will now be available, too.

Last week we recevied an upgrade kit for each X650 sold through the shop plus 2 extras for customers from other shops who may be bringing them in. We have however only "sold" one X650 and that is the one I ordered in August and have still not received. So oddly SP is distributing lots of X650 upgrade kits but no X650's yet.

The upgrade kit consists of a new diaphragm with a low friction coating on the center plate and a new "X650" decal to indciate that it has been upgraded.

 

[DA Aquamaster]

There was one decent response as to the difference between the two regs s600 and x650. The SRP is the same between the two regs, what is the difference, why does SP make 2 regs the same price? Are the regs built for the same type of diving? What is the difference?

In the past, Scubapro marketed both the D400 and G250 as high performance regulators. Both had very high perfromance, the difference was that the G250 was more like an American muscle car while the D400 was more of a European sports car with finer lines and smoother perfromance. One of the benefits of the D400 was that it was much more automatic than the G250 in that due to its case design it could deliver maximum performance and minimum cracking effort (as low as .5 or .6" of water) with no adjustment needed due to the divers attitude in the water as is required with the G250 (and S600). The D400 really did have a much more refined feel to it than the G250 or S600.

On paper the workhorse G250 could turn in lower numbers in terms of work of breathing but it did so with a rougher feel and with a positive pressure aspect to it. The thoroughbred D400 on the other hand would deliver as much air with a lower cracking effort but with a much more natural feel. So objectively the G250 was the better reg to divers driven by numbers, while subjectively the D400 was the better reg for those divers who liked smooth and natural air delivery to go with their high performance and both had a distinct place in the Scubapro line up.

Scubapro has since added small sized regs with the R380/390 and S600 being smaller versions of the R190 and S600 with identical internal parts in slightly smaller cases and with smaller diaphragms. The redundancy in this case is to have something to sell to the misguided souls who think a smaller second stage is better.

The X650 was supposed to replace the D400 in the SP line up but it remains to be seen if it will really do so. If SP would ever ship mine, I'd be able to let you know.

 

[liberato]

...Scubapro has since added small sized regs with the R380/390 and S600 being smaller versions of the R190 and S600 with identical internal parts in slightly smaller cases and with smaller diaphragms.

Justin, you probably got it from the context but he meant to say: "...the R380/390 and S600 being smaller versions of the R190 and G250..."

DA Aquamaster, you will be happy to know that you will be getting your new X650 next week. Mine came in on Friday but I live in California so give it a couple more days. Instead of fixing mine they just gave me a new-in-box one so they are definitely shipping new product now.

 

[Humba]

I tested the x650 on saturday @ scubatoys. My current configuration is g250/mk25 and I read so many great things about the x650, I had to do a back-to-back comparison. After about an hour in the water, my subjective feeling is that the x650 breathes slightly better than the g250.

 

[DA Aquamaster]

My X650 arrived this week, I picked it up on Friday and then dove it today.

Before getting it wet I put it on the test bench and found it was delivered with a cracking effort of 1.4" with the adjustment knob all the way out and in the process of tunning it to one of my Mk 20 first stages (operating at 125 psi IP) found (surprisingly) that 1.4" was also the minimum setting achievable without a freeflow. Given that most regs in this class can deliver minimum cracking efforts on the bench of .8 to 1.0 and that a D400 can deliver cracking efforts in the .5 to .6 range, this did not bode well for the in water tests.

As I started my decent I immediately found that in a normal swimming position I needed to crank the adjustment knob in almost all the way (exactly 1 turn out from the fully tightened position) to stop a slight freeflow following each inhalation. This freeflow was not great and consisted only of a very small and almost un-noticed trickle of bubbles, but it was none the less a concern on a deep dive in 38 degree water where the loss of air is both unacceptable (to me) and poses a potential threat to freezing up the first stage. Unfortunately, when adjusted to eliminate any stray bubbles out the exhaust valve, it breathed like a rock (post dive testing on the bench later indicated a cracking effort of 2.2" in this condition).

On a positive note, over the course of the next 30 minutes the reg displayed exceptional cold water perfromance and showed no signs of icing. My D400, a very good cold water second stage, in similar conditions will not freeze but will spit the occassional tiny piece of ice at me through the mouthpiece. This did not occur withthe X650. So the X650 would appear to be very suitable for use in extremely cold water. Of course this was qualified by the need to crank it down to eliminate the freeflow which would otherwise put an additional cooling load on both the first and second stage.

On a post dive inspection, part of the cause of the slow trickle out the exhaust valve was obvious. Given the case design and the location of the diaphragm and exhaust valve, in a normal slightly face down swimming position, the upper edge of the exhaust valve is nearly a inch and a half higher than the center of the diaphragm. In fact, in terms of case geometry fault, a normal swimming position is nearly the worst case position for the reg. But this really does not explain the need to increase the cracking effort to 2.2 inches to fully stop the freeflow only slightly higher than the minimum cracking effort of 1.4 inches should be adequate to prevent this.

The X650 uses a huge oval shaped exhaust valve that may be contributing to the problem. A possible solution would be to temporarily tape the upper half of the exhaust valve to the case and thereby reduce the distance from the lever to the "top" of the exhaust valve to see if this reduces or eliminates the problem and to see if this would make the 1.4" cracking effort the lever and valve combination is capable of producing usable in the water without a slight freeflow.

I should note that I compared the new X650 to my 100 or so dives since serviced last D400 head to head during the dive with the D400 delivering a less than optimum .8" cracking effort (on the test bench pre and post dive) that suggests it would benefit from servicing but which was none the less far better than the X650 in terms of cracking effort. The D400 breathed substantially better in the water than the X650 and in fact the old reliable (and just serviced last week) Mk 3 Balanced Adjustable on my deco bottle also breathed noticeably better than the X650.

It could be that my particular X650 just plain sucks, was not properly adjusted at the factory, and/or is not representative of the X650 in general. I plan to fully disassemble it, try to identify anything that could be causing the problem and ensure it is properly adjusted to SP specs. (once I find the service guide for it, as it is not yet up on SP's website).

But, after an initial dive with it, I am really not impressed with it at all and it is going to have to improve a lot before it has any hope of replacing my D400 primary reg.

 

[DA Aquamaster]

An update... I serviced the X650 and noted the poppet had a substantial seating groove in it. I replaced the poppet and it will now deliver a cracking effort on the bench of about .8 which is about where it should be performing.

Now it's just the exhaust valve issue....

 

[liberato]

...the poppet had a substantial seating groove in it.

How do you think a new one would be grooved already? Was it new in box when you received it?

 

[DA Aquamaster]

My guess is that my particular X650 has been sitting in a warehouse for the better part of a year waiting for SP to solve the initial problems and design and install the updates. Over time, the pressure of the poppet against the orifice will cause the seating groove to deepen and increased spring pressure (and in turn increased cracking effort) is then needed to effect an air tight seal. In normal use it would not be much of an issue as the reg would be due for annual service anyway.

In what was largely a keep up with the Jones effort, SP introduced a new balance chamber design in the S600 that essentially lifted the poppet off the orifice when the reg was depressurized. This did great things for seat life, but caused some other problems and was (I believe) discontinued on the S600 after the first year or two of production. This feature is thankfully missing on the X650 which uses the older/current balance chamber and adjustment knob design.

It's just speculation on my part, but since the recent X650 upgrade only involved the diaphragm, there was no reason to mess with or change anything in the air barrel. My guess is the new diaphragm was installed, the new sticker was stuck on it, the reg was checked/adjusted to ensure it did not freeflow on the bench and then it was sent to the dealer. If this is the case, it will potentially be a common problem with many of the recently shipped X650's. The good news is that since the poppet itself is new and unworn, you can just replace the soft seat in the end of the poppet and the parts cost is only $1.00.

My plan is to dive it again (as soon as the weather permits) in it's present form to see how it acts in the water. If I still have problems with air leaking out the upper edge of the exhaust valve with the consequent need to increase cracking effort to unacceptable levels to stop it, I plan to insert a small piece of open cell foam rubber in the exhaust T to cover the upper half of the exahust valve and provide a slight pressure to keep the upper half closed. This could be easily done during a surface interval and the piece could be readily removed under water if the need arises.

If that does the trick without creating a noticeable increase in exhalation effort, I'll consider sealing the upper edge of the valve with a couple small drops of silicone adhesive and call it good - and give my .02 to Scubapro.

I am less negative today than yesterday and I still think the X650 has lots of potential, but I still have the feeling that it is not getting the care and attention that is needed to fully realize that potential.