Motorcycle Repair: jump starting, wet cell battery, everstart maxx jump starter

Question
Is it ok/safe/etc to use an EverStart maxx Jump Starter HP450-2to jump start a motorcycle w/12v battery?

The portable jump starter says "500 amp starting power", taking its power from an 18amp/hr battery.
If it is safe, they recommend attaching the black/neg lead to the engine block. I'm not sure where to place this lead, because I'm fuzzy on what and where exactly the engine block is.
thanks. (Yes, I plan also to call the company.)


Answer
Jump starting a motorcycle with high amperage sources can damage the electrical system on some bikes. Better to remove the battery, charge it slowly... 1 amp and then check it to see if it is capable of holding a charge or not. Most m/c shops have battery testers to load test the battery to find out if it is just holding a "surface charge" or not. A big surge of current into the m/c electrical system will probably fry the battery and or some expensive electronics, depending on what you are riding.
Anytime you are jumpstarting anything, attach the + Positive lead to the positive terminal of the battery and the - Ground lead to the engine assembly, motor mount/bolt and/or any clean metal connection that the electrical system is connected to. The jump starter is just another power source, but if you put both leads on a wet cell battery the sulfuric acid fumes coming from the filler caps can ignite with a spark and blow the battery and acid all over you and the vehicle, thus the admonition to attach the ground away from the battery itself.

Bill Silver