update.
Turns out the front wheel hub was full of mud.
Once cleaned out it worked.
Who guessed the cogs are plastic ?
How it got in there is a mystery.
Anyhow that fixed and another fault that 2 bike fixers cannot fix.
The throttle....( the main reason for keeping this problematic old beast )...
hi I have an older alpino,its gone to the menders with an odd fault.The front wheel will only go forwards,its like the brake is on and impossible to move in reverse,makes no difference if power is on or off. Any ideas