*MADE in USA* Class ZZ Steel Large Diameter Pin Gage. Available in sizes from .608" to .615" Minus tolerance +.0000 to -.0002 for checking the throttle bore on a Honda/Clone box stock kart racing engine.

Most engine builders are aware that the stock carburetor bore is the restrictor plate for their race engine and that getting the maximum allowed bore size, will improve engine performance. Stock factory carburetor bore sizes vary quite a bit. This pin gage will allow you to determine the stock size or determine if a carburetor has already been modified and/or check for final sizing after modification.

Please Note: These are NOT considered the proper tool for performing post-race technical inspection and are designing to provide a method for inspecting and determining actual carburetor bore both stock and modified. Post-race technical inspections are performed with blade type no go gages. The reason for a blade gage is that, it can determine if a carburetor bore is oval shape and possibly larger in one direction and smaller in a 90 degree direction. With a solid pin gauge an oval shape bore at the maximum limit could check legal, while a blade gauge would check the same bore illegal.

We recommend performing modifications and maintaining a diameter approximately .001 undersize. This will allow for variations in tech equipment and even carburetor material change from torqueing and running conditions. The minus pin is better suited for engine builders to check components for technical inspection providing the ability to have a finish size slightly under the maximum allowable size.

Pin Gage Spec:

• Each pin has a centerless finish of 10 micro or better
• Size electro-etched on side of pin
• Heat treated to a hardness of 60/62 Rockwell "C"