Very sad to hear this news and agree with all that's been said. John obviously loved his cycling, was great company on club runs, with snippets of advice, constructive criticism and motivation to keep you going. His company will be missed by all the Oggies that rode with him, fellow Jif cyclists and the wider cycling community in South Wales.
As others have said he was strong on the bike but always helping others to push themselves. often beyond what they thought they could achieve. Several times at the back end of a club ride I'd try and desperately hold his wheel as he towed the stragglers back to Brackla; me apologizing for not coming through to try and work and John would always say the same thing " we're both working Andy, we're both working".
Sincere condolences to family and friends.