battery electric mountain bike

My battery use to work and charge properly for about 50 charges over the last year. I have done about 1200kms on this battery so it has done well. Then at some stage I realized I only got half the power out of the battery and then progressively down to about 25% within a couple of charges. I did...

Hi, I have a Carrera Centos mountain bike which is a bout 6 tears old now and I wish to convert it to battery powered, can anyone please advise me which sort of battery/conversion kit may suit the bike? and are there individuals in the South West UK who may be able to fit the battery kit for me...