[RodgerMillan]

I'm having issues starting up my 2016 cbr250r that gets infrequent use.
I have a battery charger to prevent the battery from dying and I check the voltage frequently. I'm wondering how I go about checking for a spark on the spark plugs

Here's how you with the spark plugs:
Test the spark plug ignition by disconnecting the spark plug wire from the spark plug. Hold the end of the spark plug wire close to a metal surface. If the spark plug is good, you will see a spark or you'll hear a crackling noise. This means that voltage is getting through the wire to the spark plug.
More details about this can be found here:

How to Test Spark Plugs

When you experience a sluggish engine, there's a good chance that you could have a bad spark plug. Difficulty cranking, low momentum while running or sluggish performance in your engine can all mean spark plug failure. You can take your problem to a professional mechanic for a complete...

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