To ensure absolute precision and to bridge any issues of engineering tolerance's, Trampa has released 2 types of plastic bushing to make the king pin fit as accurately as it should..... One bushing has a base of 2mm whilst the other has a base of 2.5mm. Seeing as each truck has 4 bushings this .5mm difference allows the maker to bridge a maximum of a 2mm tollerance, more than whats measured on the product. Set includes 4 x 2mm bushings 4 x 2.5mm bushing
The precision made Kingpin Bushings locate the Kingpin in a wear-free position between the hanger & Baseplate.
The Kingpin bushings are a small item & are subjected to a lot of forces and through normal/regular use they will ultimately need replacing over time. Depending on what surface you are riding on will depend on how long these bushings will last you. So to make sure your trucks are always performing at their best inspect these Bushings regularly (preferably before riding) & in particular replace any that are showing signs of wear & from time to time replace them anyway...
The difference between the four bushings is the thickness of the base. The different base sizes are 1mm, 1.5mm, 2mm and 2.5mm. 2.5mm is the standard size we work to. As all trucks have 4 bushings this .5mm difference in each of the bushing bases allows us to bridge a maximum distance of 2mm (4x.05mm=2m) resolving any foreseeable problems.