Vintage connector sells tons of good motorcycle harness stuff. I bought some of their crimpers, the type with the roll-over jaws, as martin shows, and they work great. I don't do anything special when building/repairing a harness, other than making sure all the brass is clean and in good shape.
As an aside, a small soda blaster can be used in old connectors to clean up the brass if you can't get the terminals out to do a proper external clean.
If you are removing the pins it is worth replacing them, they can be sourced from company's such as "Wurth" Don't forget aside from corrosion the female sockets loose spring tension over time which leads to arcing and volt drop issues when under load (same effect as a loose battery terminal)
When I need to clean up some nasty electrical connectors I hold it in a rag and spray battery terminal cleaner into the connector and let it soak for a minute. Then I wash it out with non chlorinated brake cleaner and blow it dry with the air hose.
The brass parts come out nice, clean and shiny. The battery terminal cleaner neutralizes any acid and corrosion. Then I fill the female connector with dielectric grease and plug back together. We've used this trick on at least 20 bike resurrections with great success.
The Rust Bros. Garage Collection
1974 Honda CB 550 K0
1975 Honda CB 400F Super Sport
1977 Kawasaki KZ 1000 LTD
1980 Suzuki GS 1100E
1981 Suzuki GS 1100E
1982 Honda CB 900F Super Sport
1983 Honda CB 1100F
1984 Honda Sabre 700
1984 Honda Interceptor 1000
1994 Kawasaki ZG 1000 Concours