Yes, that sounds about right. Zero claims a sustained top speed under nominal conditions (no headwind, flat) of 80 mph = 129 kph. This is limited by controller (primarily) and motor (secondarily) thermal capacity; operating at high power for a period of time causes the components to reach their thermal capacity and restrict power.
There are really three stages to the thermal indicator lights (see page 4.13 in the owner's manual):
Stage 1: Temp light blinks, indicates to the user they're nearing the limit.
Stage 2: Temp light goes solid, motor restricts power.
Stage 3: Controller stops powering motor to allow the bike to cool
I think normally Stage 3 shouldn't be reached. Perhaps if ambient temperatures are very high in conjunction with high speed riding..
If you're riding uphill or into headwind, then the temp light can come on even below the nominal sustained speed limit.
Zero's cooling strategy for the 2013 bikes is fairly simple, passively cooled components not in the direct airstream in combination with a relatively small motor controller. It's simple and works fine for moderate riding conditions, but is a limitation at sustained high speeds or in race conditions.