Instrument cluster odometer resetting

The battery is 6 months old it's a yusa I thinking it could be reg/rectify it's the 1982 original I think all Japanese writing on front of it

 

So I am back again the problem resurfaces once I let the bike sit for a day or two the clock and odometer resetting again. It worked great for few days then let it up for day or two and back to square one

 

Does the bike start normally though?

 

Is there a battery for the trip odometer memory? If not, would it be difficult to wire one in?

 

Yeah starts on the button no problems there and the light gets brighter as you rev the bike in neutral. It has 12 or so amps sitting in the bike and goes up to 13.5 under load of 2k revs I probably just being picky TBF. Just a a mpg nerd I like to know what distance I am doing don't care bout the clock it's the trip odometer I want lol

 

For lads here on forum no me yes I have biked for 13 straight years and learned I bad with spanners

 

You mean VOLTS

 

Sorry yes volts lol for its age everything else runs smooth I can. Get over it but thank you everyone for the pics the suggestion and problem solving