Aye Richard,
The Wemoto listing supplied by Steve (Manxie) works fine. Don't try to save a bob or 2 by using the 'Swift' chain, its cheaper for a reason and singles eat it for breakfast!
Tried the 'Swift' on Sally (SRX600) and lasted less than half the miles of Regina/DID. The bike runs a chain oiler all the time and adjustment when necessary is always done and I can get 12,000 miles from a Regina/DID. JT sprockets are fine, never had any problems and in fact the pair on now stayed on when the new Regina went on after the 'Swift' and will last the life of the Regina.
I also ordered one the wrong size and sold it to ? in the club (sorry it's late and I can't remember who it was!) and the same problem reared its ugly head after fitting and being looked after, poor mileage.
All the best, Bill