RunRight RT F tensioners are designed for front mounting applications where access to back side or rear mounting surfaces is not possible. A single threaded hole is required to mount these tensioners. These tensioners include a special mounting screw and spacer bushing. They are manufactured with powder metal or cast iron housings, cast iron arms and inner square, come with the standard Tensys™ 10 rubber inserts, and can be used for applications operating within a -40° to 180°F (-40° to 80°C) temperature range.

Unit of Measure





N/A Chain/Belt Tensioner

Element Material

N/A Natural Rubber


N/A Elastomeric


N/A Blue

UPC Number

N/A 53277

Dimensional Data


N/A RT F27

Mounting Bolt Size

N/A M10

Outside Diameter (Dim D)

N/A 3.07 in78 mm

Overall Length (Dim E)

N/A 4.25 in108 mm

Idler Bolt Size

N/A 1/2 - 13 x 3-1/2

Dimension L

N/A 6.1 in155 mm

Dimension J-1

N/A 5.12 in130 mm

Dimension J-2

N/A 3.94 in100 mm

Dimension M

N/A 0.67 in17 mm

Dimension R

N/A 0.59 in15 mm

Dimension G

N/A 0.31 in8 mm

Dimension O

N/A 0.59 in15 mm

Dimension P

N/A 0.41 in10.5 mm

Dimension K

N/A 1.97 in50 mm

Cubic inches

N/A 79.58975 in³

Performance Data

Normal Temperature Range

N/A -40 to 180 ºF-40 to 80 ºC

Force at 20° Angle of Pretension (Normal Force Level) (Dimension F)

N/A 85.4 lb380 N

Distance at 20° Angle of Pretension (Normal Force Level) (Dimension S)

N/A 1.7 in44 mm



  • The recommended angle of pretension is 20°. This provides the tensioner a maximum capability to absorb vibrations and shock loads, while also maintaining a range of motion to address the system’s belt or chain stretch.
  • Mounting accessories into the “Hard” Position results in approximately 25% higher tensioning force over the “normal” position.
  • Inch (imperial) standard tensioner units all come with both the mounting screw and a zinc-plated idler bolt with nuts.