Difficult to chrome
We have found Zinc in a rear wheel bushing, rear sprocket, and many bolts used by kawasaki. and also on the rear wheel adjuster, which is a bitch because it is welded to the swing arm.
I have no reason to suspect that their products are any different to other japanese manufacturers. The parts acted like normal steel when dipped in nitric acid, checked with magnets, and during polishing. But we saw the problem immediately the parts went into the nickel tank. Some platers use cyanide based solutions for their Brass or copper strike plate. Cyanide will adhere to Zinc along with the brass or copper to make a solid base for the nickel. Unfortunately our tanks are non cyanide.
A large plating shop should not have a problem. With the bolts we were able to take the zinc off as it was a coating. Zinc is very popular for preventing corrosion. How do you recognise it? Basically if the steel is naked, more than 2 or 3 years old and has no signs of rust, it's probably got Zinc in it. If it is powder coated or painted, then it's tough to tell. I have to try to find a fool proof way to tell if it is present. When I do, I'll let you know.
Oddly enough adding small amounts of Zinc to steel also makes it harder and reduces the need for tempering. But it's still a bitch for us to chrome.