Hi ,i have an old cocker with quite curly thick hair . As i live in Mallorca i usually have him shaved in the summer as his hair is thick and hot , i have noticed though that it has grown back more wooly .Last year I bought an english pedigree cocker of black + white colour,his hair is lovely and silky ,I am wondering if shaving him is a bad idea ,although i would like to do the underside of his ears.Does anyone know if shaving causes a change in the growth or texture of the hair/fur .

Clipping (shaving) the coat is renowned for changing its texture, I'm afraid, and it can take a year or more of careful proper grooming to get it right again.

Clipping certainly makes a cockers coat thicker and curlier, neuturing will also have this effect to a greater or lesser degree.  To maintain a silky coat you will need to hand strip out the coat in addition to regular combing right down to the skin.  To learn to hand strip properly it is best to find someone who can actually demonstrate it to you, perhaps the breeder would show you.  You would normally clip the inside of the ears though plus a few other areas such as under the tail although I tend to use thinning scissors.