The large diameter silent insert is designed for our older style shiny aluminum spark arrestor end caps. The large diameter version fits the models listed below.

This insert are designed to reduce the exhaust note by 3–5 decibels* for a more acceptable sound intensity level.

Simply inserts into the nozzle and is held in place with a bolt from the back side.

NOTE: These inserts only fit the original "snorkel" type end caps for the models listed below. For spark arrestors with anodized end caps, see our "new style turn-down silent insert.

Fits these models with old style Pro Moto Billet end cap installed:
Yamaha YZ400F/426F/450F 1998-05
KTM 400/450/525 SX 2000-03
Husaberg FC 470/550 2001-2002
Cannondale X440 & S440 (Most)
Gas Gas 4-strokes with stock exhaust
VOR 4-strokes with stock exhaust
TM 4-strokes with stock exhaust

NOTE: These inserts only fit the original "snorkel" type end caps for the models listed below. For spark arrestors with anodized end caps, see our "new style" turn-down silent insert.

*Sound intensity level will vary depending on model, tuning, and exhaust system condition.