I picked this up at a trade show last month, and while I haven’t had opportunity to use it yet – and indeed it has limitations in terms of American motorcycles – it is a genius idea. And if it can’t be used, it can certainly be adapted.
When cables snap – or their nipples come off – the outer cable is usually still fine: in the case of the nipple coming off, so is the inner. Sadly that’s only a consolation if you can find the nipple, some solder, a source of heat and a bird caging tool to do what the manufacturer failed to do in the first place. Sorry, that’s still raw … and the solderless end that an AA man fitted is still in place but then that bike hasn’t turned a wheel in a while. When it does it will have new handlebars and a new cable.
Back at the plot, the good news is that inner cables are remarkably flexible, light and packable in a way that a whole cable isn’t, and they’ll usually thread straight down into the hole vacated by its broken predecessor.
But there’s bad news too: inner cables of American bikes tend to be thicker than the 1.5mm throttle and 2mm clutch provided, and at 1.6m or 63-inches, the length is borderline for many applications.
And, of course, there are as many nipple combinations as there are twistgrips and carbs.
Fortunately, a thin inner will fit in a wider outer, so as a ‘space saver’ repair – with the right nipples – this will still get many people home … 
although probably not if they’ve got 18-inch apehangers or a stretched frame.
One end of the emergency inner already has a small nipple soldered to it – the sort that slots into bigger ones to meet the requirement – and there is a range of solderless nipples for the other end, but not the range of Allen keys that you need to secure them. Again, that is hardly an issue to the sort of person who will benefit most, because they’ll be carrying tools.
The second kit is for a speedometer or tacho, has a range of heads to suit different instruments – with the obvious exception of electric/digital ones – and it comes with the tool that crimps the head to the cable as well as instructions.