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Timing Pulleys

Timing pulleys are drive components that are used to transmit rotary motion between parallel axes.  Ondrives.US’ timing belt pulley selection provides reliable performance with very little maintenance—generally, the only required maintenance is periodic adjustment of
belt tension. Ondrives.US’ MXL, XL, L, 40DP, and T Series timing pulleys have a trapezoidal shape, while our HTD and GT2 timing pulleys have a curvilinear groove profile. Request a quote on standard or custom timing belt pulleys. Contact Ondrives.US for more information or to discuss your unique aluminum timing belt pulley requirements.


We offer timing pulleys and matching timing belts with various profiles; due to differences in pitch, size, and tooth shape, different profiles are not interchangeable

Versatile Timing Pulley Designs

Our timing pulleys can be used for speed reduction, speed increase, or simply to transfer rotary motion from one axis to another. Timing pulleys can transfer power as well as precise position; however, the precision of the positioning depends on the groove profile and the type of belt used. Like a gear, the ratio of a timing pulley is determined by dividing the number of grooves of the two pulleys in the pair. 
Because they maintain their relative positions and do no slip or creep like flat, v-shaped, or ribbed belts, timing pulleys are used in synchronous drive systems. However, it is possible for a timing belt to jump or skip the timing pulley groove, causing the assembly to lose indexing. This can happen if the system is not properly tensioned or is angularly misaligned, or if too much torque is being transmitted.

Timing Pulley Options

We offer standard timing pulleys with no flanges, a single flange, or double flanges to hold the timing belt’s position. One or two set screws are used to fix the timing pulley to a shaft.
Generally, a pair of timing pulleys requires a minimum of two flanges and proper alignment to ensure that the belt stays in position and does not run off the pulley. The right timing pulley and flange count depends on the synchronous drive’s design, including the orientation of, size of, and distance between pulleys, among other factors.

Timing Pulley Materials

Ondrives.US can manufacture your timing pulleys from a variety of materials. The most common options are:
  • Aluminum timing pulleys
  • Steel timing pulleys
  • Plastic timing pulleys

Timing Pulley Modifications

We can modify any of our standard timing pulleys to suit your specific application and performance requirements. Common modifications include:
  • Keyway in bore
  • D shaped bore
  • Custom bore size
  • Clamp style hub (instead of set screw)
  • Two pulleys on one part
  • Different materials, such as Acetal with a brass hub
  • Special plating or finishes

Custom Timing Pulleys

Ondrives.US can supply standard pulleys and replacement pulleys to match your existing system. We can also manufacture fully custom timing pulleys to match your exact specifications. Custom timing pulleys are available in ODs up to 16”. Contact us to discuss your custom timing pulley requirements.

Contact Us for Precision Timing Pulleys

We provide precision-manufactured small timing pulleys for synchronous drives and other high performance systems. Request a quote or contact Ondrives.US today for the standard or custom timing pulleys you need.