Whinning noise

[oxtaff]

no not from a passenger but from the front off side.

I have checked pads etc and all looks OK. The noise kicks in at about 50-60MPH, no change if I touch the brakes or clutch, freewheeling does not change it. I tried stopping and keeping engine revs constant and the noise goes. It is there so long as the wheels are turning, so I conclude that if it isn't anything to do with the discs or bearing could it be the speedo cable? It isn't a metallic noise, more of a rubbing sound. It's driving me nuts so any suggestions will be gratefully recieved.