Battery Drops To 9v When Cranking

[KTMsm]

I have a cheap chinese battery CCA tester which also records the battery voltage when cranking

Generally it's pretty accurate

Had a few bikes stood over winter - charging them bought the CCA back to standard but the voltage dropped below 9v when cranking so I bought 3 new ones (2 bikes had also failed to repeatedly start after charging)

However the new ones whilst being fully charged and measuring above their claimed CCA all measured 9v when cranking

They all managed 5 starts in a row without issue (they could have done more)

AI and the internet say that 9v when cranking means the battery is on it's way out

All batteries were the mid range option with CCA above OEM spec

Is 9v when cranking a motorcycle irrelevant ?

[GreenV8S]

9V while cranking seems about right to me. Much lower than that suggests the battery is tired or the engine is taking too much torque to crank, but it's perfectly normal to see a 3V drop across the battery while it's supplying peak current. This is why cars used to use ballasted ignition systems until electronic ignition was introduced.