The International CBX Owners Association

I came back from a 50 mile ride and plugged in my Battery Tender JR and the red light came on and has been red for an hour and a half. Is this normal
operation? I have a new battery, my alternator was just rebuilt with new brushes , resurfaced drive plates and voltmeter shows 13 volts while
riding at 55mph.
I would have thought after riding the battery would be fully charged and the Battery Tender light would be green right away.

Some battery tenders are sensitive to the connection sequence. You need to connect the tender to the battery first before you plug the tender in. Try this and see if it changes anything. Also, what type of battery do you have? Some gel and Lithium-Iron batteries do not work well with the conventional tenders.

I have an AGM battery. After being connected for 2 hours the
indicator light is now steady green indicating a fully charged
battery. Perhaps the red light being on first for an hour or so
is normal operation.

I'm not certain what that tells me. My experience with the BT Jr is after a ride, i just reconnect it and the light starts blinking green in less than 5 minutes. (Steady green in about 10.) Same for both my bikes. (BT is always plugged in.) Both batteries are AGM about 5 years old.

The bike had been sitting all summer not connected to the
Battery Tender so maybe the battery was a little low and 50
miles didn't fully recharge it and the Battery Tender took an
hour or so to bring it up to the correct voltage. I'll go for
another ride with the fully charged battery and see how long
it takes the light to go green. I'll be leaving the BT plugged in
continuously from now on.