There are pulleys, then there are UR PULLEYS

As a reminder the facts provided in these blogs only apply to Unorthodox Racing products, other parts may look similar but we can assure you they are not. You always get what you pay for in the end.

We hear from the following phrase from time to time, "a pulley is a pulley is a pulley." Oh if only it were that simple. The first problem with this assumption is of course that all pulleys are the same, the biggest problem with this statement is when someone buys a cheap knock-off or copy cat pulley and it fails the buyer thinks that all pulleys are bad. Boy have we herd our fair share of horror stories over the years from these poor customers, from parts not fitting properly, to vibrations, to parts breaking and even disintegrating. With a little re-education and encouragement these customers are now happy users of UR pulleys.

The reason other pulleys fail is due to simple structural weaknesses. Although we will admit pulleys are not particularly complex to design there are some basic fundamentals that company’s who dabble in pulleys always fail to follow. Cross section thickness is essential, especially the further out the centerline of the belt/s are from the mounting face. After years of testing and finite element analysis prior to coming to market in 1997 we established strict minimum thicknesses. These minimum thicknesses are also extremely important on big power cars because during spool up as enormous forces are put on the crank and other pulleys during rapid acceleration. Another key element in the design process is how additional weight reduction is done. After exhaustive testing we primarily use holes, the copy cats tend to put slots in their parts. The problem with slots is they concentrate all the stress on a few small areas which is a recipe for disaster as cracks will form causing eventual catastrophic failure. By using round lightening holes without slotting we can evenly spread our stress loads guaranteeing structural strength. Now we are certainly not saying slots can't be used but only in appropriate circumstances. We do use slots for a few accessory pulleys because they are smaller in diameter and most importantly the belt is at the center line of the pulleys mounting point assuring the necessary strength.

So next time you hear or read someone saying all pulleys are the same just smile, try and pass on a little education but if they won't have it then hopefully they will learn the second time around.