JRC STI-R Bivvy

Part One

STI-R Bivvy Vital Statistics

• Ultra light 6061 series Aerospace grade aluminium poles.
• Fitted rain gutter system.
• Double P.U. coated 5000 hydrostatic head oxford nylon.
• Simple but brilliant zip, roll and clip, 3 way door system
• Multi position height & width adjustment via the centre tensioning strap.
• Tape sealed seams throughout for 100% protection.
• Bar stitched for maximum strength throughout
• Supplied with new heavy duty groundsheet and pegs.
• Dimensions: 2400 (d) x 2200 (w) x 1350mm (h).
• Weight – 10kg
• RRP - £219.99
  

This very versatile yet simple Bivvy system offers a wealth of setting and assembly options which allows the angler to adapt to changing weather conditions rapidly. The three sectioned, two break pole design enables fast assembly of the STI-R’s very light framework, each joint alignment is simplified by the toughened plastic female sections on each bar which makes the frame assembly a very quick affair.. By then attached the fitted tension strap, this strengthens the shelters frame and tensions it into shape and ready for pegging out.

Next, peg out on either side of the frame to elevate any chance of doing an impersonation of Mary Poppins as a 20mph gust of wind takes you and the Bivvy fifty yards down the bank. Once the pegs are fitted securely, fit the frame support bars, there are two identical bars which have frame grips at either end and these tension  the front to middle frames and the middle to rear frames. The third bar is adjustable with a frame grip at one end and a rounded spike at one end, this is for the rear of the Bivvy and should be tensioned once the bivvy is fully pegged out and the groundsheet is fitted.

The easiest way by far of pegging out the STI-R correctly was as follow:

1. Place a peg in each of the rear three pegging points
2. Then place a peg either side of the front door, once this is done, unzip the door
3. Take the supplied Heavy Duty Groundsheet and unfold, when the Velcro is pointing down you have it the right way up
4. Place the groundsheet inside the Bivvy and starting from the front, work your way from side to side securing all the Velcro fastenings on the ground sheet to the shelter.
5. Once all Velcro are aligned, then starting from the front of the Bivvy continue to peg out ensuring that the ground sheet stays in position (if you over tension the Groundsheet you will here the Velcro come apart, if this happens remove the peg, then re-attach and peg out again)
6. Once all the pegs have been securely attached, tension the rear frame support bar and lock into position ensuring the bars spiked end is securely fitted in the receptacle next to the central rear pegging point.

First Impressions

The STI-R  is a very nice piece of kit that is easy to put up - I managed it in about a minute first time but I’m sure with practice I can reduce that by a few seconds. Once fully pegged out and with the frame support bars fitted correctly it becomes a ridged shelter that has the potential to handle the strongest of winds. The three options on the door were very practical but with torrential rain on both the nights I tested the STI-R I was only able to use the clear window as I had to keep the front door shut at all times because of the swirling wind and heavy rain.
After surviving the first nights meteorological delights, I was please to see that no rain had entered into the bivvy and that all the taped seems had performed there jobs and remained 100% waterproof. Although the wind had gusted at around 20mph at its worst, I was more than confident in the stability of the STI-R light Alloy frame and its ability to withstand winds of a far greater force. Once the rain had stopped and I was able to open the door on the bivvy fully, the STI-R was bone dry in less than an hour. Even in what can only be described as “cool conditions” the wet to fully dry time was comparable to other shelters of a far greater value.

I woke up on the second morning to find that Mother Nature had tried her worst but the STI-R had coped with the 6 hours of heavy rain, strong winds and plummeting temperatures admirably. However, there was one obvious problem, condensation and a lot of it. This however is not a criticism of the STI-R because with the door being closed all night, which dramatically reduced the airflow within the chamber and also taking into consideration the outside air temperature being close to freezing. I personally believe that the majority of single skinned Bivvies on the market would have reacted in exactly the same way.

Finally the sun came out and I had the opportunity to get some air flow in the bivvy, after about an hour of having the front door open at half mast and with the sun warming up a refreshing southerly breeze, the condensation had but all disappeared.
One simple solution came to mind, as with the majority of single skin Bivvies, the addition of an Overwrap would reduce or possibly eliminate the condensation problem completely. So with that in mind and a now bone dry STI-R, I decided to call it a day and have another session with the Overwrap fitted to see how much of a difference it make to the Bivvies overall performance.

JRC STI-R Bivvy

Part Two

 

• A compact ¾ wrap to keep out the worst of the weather,
• Double P.U. coated 10,000 hydrostatic head Oxford nylon.
• Taped seams throughout for 100% protection.
• Bar stitched for maximum strength throughout.
• Dimensions: 2400 (d) x 2200 (w) x 1350mm (h).
• Weight – 2kg 
• RRP - £95.00

The STI-R Overwrap 10,000 is designed specifically to complement the STI-R bivvy.  It can be fitted in a matter of minutes to provide additional warmth and protection from the harshest of conditions. As any angler who owns a single skin shelter will tell you, virtually all single skin shelters are prone to condensation but once an overwrap is fitted to the majority, and this drastically reducing the problem of condensation forming. So now to test the STI-R with the Overwrap fitted to see if the second skin would eliminate the problem of condensation I had previously experienced whilst field testing the bivvy.

After I had erecting the STI-R, fitted the groundsheet and had a can of fizzy Apple Juice (you know, the one with 2 arrows on the can) I removed the Overwrap from Stuff bag it comes in and preceded to un-roll it. It came supplied with four additional pegs which are essential to the performance of the overwrap as you’ll discover later.
Once full opened I found the fitting of the overwrap to be a simple as you like.

The front of the overwrap has an elasticated edge; underneath this is a web strap with a metal retainer which fits onto the proud spike on the front frame support bar. Once the retainer is in place, you simply place the overwrap over the bivvy and by using the peg already in place secure the rear centre pegging point, this will then gives the overwrap its front to rear tension.

Then working from left to right and side to side, secure all pegging points as you go, leaving the front 2 pegging points on either side till last. These remaining pegging points can then be secured by using the four pegs that are supplied with the overwrap and they add the final tension to the structure.

Over the next seventy two hours the weather was to say the least variable. Upon arrival at the lake, the temperatures were in the upper eighties with warmer weather expected the next day, giving me the opportunity to have at least one night with the bivvy fully open, brolly style. With the night settling at a very comfy 14 degrees this wasn’t the weather I wanted for a field test.

At about 4.30 AM, I was awoken by the distinctive sound of my receiver sounding the first run of the day. After dealing with my first fish of the session, I proceeded to inspect the inside of the bivvy for any sign of the dreaded wet stuff, not a single drop.  To be honest, I would expect the condensation to be minimal even with a single skin on such a pleasant night, the jury was still out.
The morning air was misty on my second night but still the problems I experienced on previous sessions with condensation seemed to be a thing of the past, all was looking good, may be the overwrap was doing its job?? I desperately needed some cooler weather to prove the true benefits of using an overwrap will eliminate or at least reduce condensation in the STI-R.

The big test was now in place as the weather on my third and last knight had changed for the worst or in this case the better. With the temperature dropping to 7 degrees at best during the night and a cooling south easterly wind blowing straight into the bivvy. By 23.00hrs I had to lower the side panels on the bivvy to reduce the wind chill inside, let’s see what the morning would have to offer.

After what can only be described as a very refreshing night, I was woken by a very strong gust of cold wind blowing into the STI-R at about 05.00hrs. With very little cloud cover and a heavy mist rolling from the lake straight at me if the overwrap was to make a difference this was the morning to find out. So once out of my bed and after my morning brew I had a good look round to see how the overwrap had performed.

Final Thoughts

On the last morning the overwrap was covered by a heavy morning mist and with the bitterly cold wind blowing straight into the shelter, cooling everything inside, if condensation was going to form, this would be the morning. However, after closely inspecting the bivvy I found no signs of the wet stuff anywhere inside. 

The STI-R Overwrap 10,000 had conclusively shown that when fitted, it does reduce if not totally eliminate the problem of condensation even on the coldest of nights and in very damp conditions. After field testing in all weather systems, UKMA would recommend the STI-R & STI-R Overwrap 10,000 to any angler who wants an all season shelter, at an affordable price.

For more information on any of the JRC products, please click the image below to visit their website.