Robert , this is your mother . Please refrain from the language and let the people have their say without getting us struck down .
I too have replaced more than my fair share of valves, both on my North kites and on almost every other brand that happens to pass thru our little bit of Tropical paradise. Discussions with other retailers indicate to me that this (humidity) hassle is very wide spread across most brands. Got an email last night with the following info re efforts to fix the problem:-
"For 2011 They have changed the following:
Supplier of raw bladder material
Moved production from China to Sri Lanka to a manufacture who is working with the European Automotive industry.
Changed glues.
Changed cleaning process prior to gluing.
Tested the new system in an oven with a bowl of water underneath to create maximum humidity.
There have been no 2011 failures so far"
I have had great product support from North for years, but this problem really is a bitch! Hang in there and please, try to be constructive with your input (hard as it is). You are not being ignored and they are working on it. Geoff
I could not count all the north valves that we had to fix in the shop. But I would guess at least 80 valves where repaced by 'u-stick' here :D
perhaps every north kite should come with a compatible set of cabrinha bladders, what does a set of bladders for a 16m kite cost?? less than 200 stick on valves i bet.
i had a set of 06 Naish bladders once, sat in a bag for two years, when i pulled them out all the valves fell off.
That's great Bo Diddly
Well , we have received some contact from North .
That they assure us that they doing things to resolve the problem. That's great but we are still stuck with a heap of kites which may well deflate at any point and more cost .
Good luck with your next purchases .
I have been using North kites for awhile now, and the only valve that I had peel off was from a 9m Rebel that I bought off a girl in Townsville. I had a close look at the design and concluded that it was flawed, because the valve glue base is stuck to the OUTSIDE of the bladder. I bought some pool repair glue and put the glue on the TOP of the flange and inserted the valve assembly into the round hole on the bladder. Now the glue surface was pushing up against the INSIDE of the bladder wall. This then created a mechanical advantage. The bladder was then pumped up slightly to create even pressure on the flange as the glue set. The only cost was the glue ($12), as the original valve was re-used. I have not had any further problems with that particular valve since, and if required, you can be out on the water much sooner than the regular fix, because that relies ONLY on the strength of the bond.
Yeah , I was thinking about that the other day . It seems obvious really but there must be production problem I guess.
This obviously a problem across many kites in our climate . Anyway we will watch this space to see if manufacturers can lift their game
so after wearing much cabrinha scorn ever since i bought the damn thing, and always wondering how it would be to ride one of those (not so scorned) 'cool' kites...
i am now in the process of researching for my next buy.
it is quite simple really. i have never ever had a malfunction with my kite. i have slammed it into beaches and had it rumbled etc etc.
the only damage was carrying it parcelled in my harness and covered in sand back up a beach and wearing a small hole in it from the rubbing. my fault.
now i know why cabrinhas are supposedly the only ones in the trees!!
all the rest blow their loads getting pumped up and never leave the ground!!!!!!
LONG LIVE CABRINHA!!! STICK YOUR OTHER DODGY CR@P UP YOUR ARSE!!!
HA HA HA HA. he who laughs last is the one who has never had to fix a valve and cant relate to this discussion. with joy.
lol... Cabrinha you say... hmmmm maybe... after all... i didnt realise i was on a "euro" kite aaarrgghh!
... Kiteforum has some guys with valves problems to, check it out:
kiteforum.com/viewtopic.php?f=1&t=2365032&start=0&hilit=cking+north
Info below was taken from one of the posters who sounds like he's in the know:
Valves falling off is so annoying, I can sympathise with anyone who has experienced this.
I think every brand can hold their hands up and say they have had valve problems at some point: I have heard stories about al brands. Here's what goes wrong...
The valves are stuck to the bladders using Ultrasound Welding (sometimes called RF Welding). The Ultrasound energy excites the surface molecules on the two bits of plastic being welded and they vibrate which causes heat. The plastics melt and they stick together. The technology is used in a huge range of applications including welding the two halves of a washing machine drum together so the resulting weld can be as strong as the material(s) itself.
Now here's the problem with valves on bladders... Ultrasound Welding only works with thermoplast plastics and not thermoset plastics... (an example of a thermoset is the plastic used to make domestic electrical plugs - they won't melt wehen they get warm, but eventually burn [oh and the UK plug is the best in the world, no arguments ] a thermoplast will melt and then set again when it cools) The bladder is a thermoplast but the valves are often thermosets so a small disk of thermoplast is put between the valve and the bladder... this is what melts and glues the two together. When Flexi experienced a problem, it was because the factory used the wrong type of plastic disc... one that melted again at 40degC So, as well as sending loads of replacement bladders out, Flexi put in a control at the factory whereby at the start of every batch of bladders, a test bladder is made and then baked in an oven at 120degC and the valve is then checked for adhesion.
That's not the whole story, I believe... I think something called process variation also plays a part. There are various parameters that can effect the adhesion of valve to bladder... the energy intensity setting on the Ultrasound Welder, the dwell time (how long that energy is applied for) and several other environmental factors. All these need to be controlled to get a consistent result... it is not possible to bake every single bladder to 120degC and between checks, there is a possibility that some process parameters could change and cause a poor adherence. Some factories (and I do not just mean Chinese factories, I have seen this in many factories in and out of the kite industry) are not always good at process control... i.e. making sure all significant parameters are kept under control and within predetermined limits. Improving that is not space age solutions, it is widely used manufacturing technology but it does require someone do some work!
The other option is double sided tape... Airtime use this. It is a good idea, although much more expensive I believe (and judging by the cost of one U-Stick valve!) I've seen double sided tapes that are used to stick the badges on the back of cars and they are not easy to pull off. There are thousands of types of tape out there but it is definitely more cost than a small plastic disc and a Ultrasound welder!
And if this little ramble helps some other brands (I'm sure they all know what they're doing) then good, having valves fall off within 2 years of buying a kite sucks!