New battery time..
 

Its time to put a new battery on the Duke,i've had it 8 years and not sure how long its been on the bike before i had it.Optimate keeps reviving it but its well past its best now and its just a constant gamble that it will start the duke when i'm out and about.

Hear good things about Odyysey batteries (good cranking power..ooer mrs).
The battery im replacing is a YB16ALA2.

Any pointers ?

Cheers,Moggers.

This battery, the Varta YT12 B4 is excellent - I've got it fitted to my ST4S.
Tayna are an excellent company too.
I couldn't locate an Oddysey to fit the 4S which has the smaller gel type battery like yours, they only semed to supply for the larger lead acid battery size of the 916 etc.
Click here - Tayna Varta YT12 B4

I did fit an Odyssey to my 4s... that is a squeeze. I have to relocate slightly the ECU, saw bits of the battery tray and use a huge tie up strap to hold the battery.

... starts everytime no problem now though!