I can only add my thoughts here, but having worked with Harley twins of various sizes we had a lot of issues with apparently weak batteries when starting those high compression vee twins.
When we researched a little deeper, the culprit was a non-HD battery we offered as a cheaper replacement. The figures that matter are the 'Cold Cranking Amps' or CCI, which the manufacturer will declare on any adverts or info etc.
If that hits the target, and it's cheaper/smaller/lighter etc, then the jobs a good 'un!
