Mike Roderick, one of the founder members of the group, said: "Keep Cardiff Blue has a single aim; to restore the traditional and historical identity of Cardiff City.
"We have absolutely nothing against Vincent Tan and we appreciate the financial investment he has made into our club.
"However, this re-branding has caused a great deal of consternation among Cardiff City fans. To date, there has been no logical business case put forward by Mr Tan or the Club so we can only assume it is simply a personal preference."
The letter is below:
http://keepcardiffblue.co.uk/wp/?p=107
Dear Tan Sri Vincent Tan,
We, the undersigned, are writing to you as supporters (and customers) of Cardiff City Football Club. We are deeply shocked and unhappy at the news that Cardiff City's traditional team colours and badge are to be changed for the coming season.
Cardiff City adopted blue as its preferred team colour in 1908 and the Club is known throughout football as "the Bluebirds." The decision to play in red next season with a dragon crest is deeply mystifying to many and is unwelcome to all but a few Cardiff City supporters.
To some of us, Cardiff City will feel so fundamentally different in its re-branded form, to the Club we have loved and supported for many years, that we have asked the Club to cancel our season tickets or will refuse to buy a new one. Many others will continue to attend matches but will actively protest against the changes in lawful and respectful ways, for example by refusing to buy any merchandise from the Club.
We want to make it clear that we very much appreciate the investment that you and your compatriots have made in Cardiff City. We know that without your involvement the Club would have struggled to continue, let alone enjoy the level of success we have seen in recent seasons. We welcome your continuing involvement and your desire to make the club even stronger and more successful in the future. Whilst recognising that your investment in the Club entitles you to make commercial decisions and set strategies, as loyal Cardiff City supporters, we want you to understand the depth of feeling that has been generated by the re-branding issue.
We completely disassociate ourselves from the small number of people who reacted to your plans with disrespect and insults. We want to assure you that the overwhelming majority of Cardiff City supporters bear you no ill-will, though they feel strongly that the Club's identity and traditions should remain.
We want you to know that the abandonment of Cardiff City's traditional, historical identity feels like an insult to many loyal supporters of the Club. We feel sure that no disrespect was intended but the fact remains that news of the total re-branding of a community-based football Club has been greeted with disdain, not just in South Wales or the UK but around the world.
What you have done is not just unacceptable to many Cardiff City fans. Meddling with a local club's one hundred plus years-old traditions for marketing purposes is viewed by football supporters throughout the world as the unacceptable face of modern football. To many, Cardiff City has become a laughing stock and the name is now synonymous with all of modern football's ills.
We urge you to reconsider the direction the Club is taking and to restore Cardiff City's traditional identity and colours. In doing so, you will restore your own reputation and that of our football Club.