I use them all the time.  I see no reason that a fully-charged jump pack would not start a motorcycle, even a Savage that needs all the juice to get the thing started.  

 The model you show has protection for reverse polarity which is a plus.

I use a similar jumper. When the car ship comes in there is always a bunch that need jumped to get them on or off the ship. Way lighter and more powerful than those 50lb conventional style jumpers. However I would use caution on those lithium ion batteries when jumping , READ THE INSTRUCTIONS for the battery.