i was talking to wcw today about this 5mm stuff & they recomended the 8mm stem to 6mm barb, heat the hose to fit it & it gives a much tighter connection
We have had these new red 5mm stem to barb adapters made specifically for 5mm ID hoses.
These are best fitted with just a little heat such as 10 seconds in boiling water.
In our testing without any clips/clamps fitted they gripped the 5mm ID hose better/harder than the 6mm stem to barb adapters.
The reason is that to fit 5mm ID hose over the slightly larger 6mm versions (which are larger than 6mm in order to grip on to 6mm ID hose) the hose has to be heated more and stretched slightly more. This then means that the PVC hose has lost some of its elasticity which means it cannot shrink back quite as tightly.
The 5mm barbs are slightly smaller (although still larger than 5mm in order to grip the 5mm ID hose) which means the hose does not need to be heated or stretched as much and therefore retains it's grip ability to a greater degree.
Only a small difference but we thought it worth making them specifically for this size hose as most water-fed poles now have 5mm ID hose.
Of course the above is just based on our findings and testing
