I have an old Pioneer KEH-8080B radio cassette that I am trying to fit
to my motorcycle.

The problem is the wiring to the speakers.

I have connected all the power OK but have only got green, green with
black tracer, grey, grey with black tracer to connect to four speakers.
I believe the grey is the front left and green is the front right.
Where do I connect the other terminal on the speaker?

Any help gratefully received.

Following a search I have found the original installation manual. I am
posting the information in case it is usefull to anyone else.

Connections are as follows:-

red To electric terminal controlled by ignition switch (12v DC)
ON/OFF
orange To terminal always supplied with power regardless of
ignition switch position
yellow To lighting switch terminal
black Ground
blue To auto-antenna power terminal (Max 300ma 12v DC)
green Left speaker front
green/black Left speaker front
grey Right speaker front
grey/black Right speaker front

Rear speakers are from the din plug connection through a seperate power
amp.