Time to call on the collective wisdom that is the STW forum......
I have a customer who is handicapped but rides to work each day and needs a new helmet. The big problem is that he has almost no movement in one hand and only limited dexterity in the other so cannot operate a normal 'click together' buckle. His current helmet is a full face design with a motorcycle type 'double D' buckle. With this he can loosen the strap enough to get the helmet off without completely undoing the buckle and then retighten it just be pulling on the strap.
I can't find any suitable replacement from any of my usual suppliers, do any of you know different?
I can't think of any helmet buckle that wouldn't cause problems however i would think if he took it to a taylors they would be able to cut out the clip and sew in a double D fastening for a few quid.
Other thing to concider may be a helmet with a rock lock style twisty knob at the back to secure it on the head that way so the the buckle is less important.
take a look at Abus helmets, the push through buckle is one hand friendly
http://www.zyro.co.uk/brand/ABUS/ABUS/ABHBUCKLE/HELMET%20CHIN%20BUCKLE%20RATCHET.aspx
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This Bell helmet has the twisty knob helmet adjustment i was talking about, if you look at the 360 view you can see it
http://www.chainreactioncycles.com/Models.aspx?ModelID=69629
Bell call it ergodial
"Ergodial: The ErgoDial Fit System brings one-handed adjustments to our Universal Fit helmets. A simple press of the button and slide of the dial brings firm, snug and comfy stability"
My youngest has a giro ladybird helmet with the slider buckle like in simon's post. Dead easy to use 1 handed. Recommended as its also inherently adjustable.
or maybe get a extra long velcro strap sewn on with a D loop and a stop at the so it will come off his head with coming out of the D loop.
the stop could be another piece of strap sewn at 90 degrees as a T peice.
Could you modify the strap and use velcro maybe? Or is that a really bad idea!
Personally I'd sew a longer strap on one side and replace the buckle with one of these
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He'll be able to do the same as now, just pull the buckle to loosen, pull the strap to tighten. 5 min job with a sewing machine.
...in fact I've just had a look at my Hex and exactly the same result can be achieved with the existing strap and buckle without any sewing. Basically un-thread one of the ends and use the adjuster to tighten and loosen the strap. The mrs's Decathlon helmet is the same. Not quite as neat, but pretty simple.
Thanks for the ideas folks. There's a woman locally with a business altering clothes that I may talk to and I'm also now wondering if I can use a toe clip strap in place of the buckle to adapt a helmet.
I think the modifying the helmet straps to take a different buckle is the best option.
Not sure i'd want a metal toe clip strap around by neck, why that would be so much worse than a plastic one i don't know:0)