DIY JIS – Japanese International Standard Screw Driver: Stop stripping screws!
Hav you ever wonder why you keep stripping your motorcycle screws? Well.. this is probably because your motorcycle is made in japan and you are using an american screwdriver on the bike. In north America we tend to use philips screw heads which is intentional cambered for use in automotive manufacturing so the bit would camber out and prevent torquing off the skew head. This design how ever is more prone to stripping. The Japaneeese have came up with their own version of the phillips called the JIS. The Jis bit uses more precise angles rather than foundered edges to prevent stripping. It can be a challenge to find these screwdrivers locally or even online with out costly shipping prices.. so like any good DIY’er i decided to make my own.
How do you tell which is which? As you can see in the image below the JIS has a much flatter tip where the philips is rounded. The other main difference is the bottom angle is at 26.5 degree rather than 19.
How do you identify a JIS screw? Just look for the dimple!