These adapters fit neatly into the stock plastic end cap by replacing an existing rubber grommet (see installation instructions for more info). The adapter provides just enough exposed tube length to mount a TRS-1 spark arrestor external to the plastic end cap. The inside diameter of the adapter exposed to exhaust flow is equal to or greater than that of the existing tube so no additional flow restriction is created. Use of this adapter allows the spark arrestor to be mounted outside of the end cap for easy removal & cleaning. Note TRS-1 spark arrestor must be purchased separately or in the TRS-1 & BT-5 spark arrestor KIT part# TRS-1-BT-5.
Since mid-2025 Beta started using Tamper Resistant T15 screws for the endcap, because this is not a common driver interface: a Tamper Resistant T15 driver bit is included with this adapter.
Note: Anodized color will fade due to heat, UV light, & chemical exposure.
Installation instructions Rev.1
Applications: Beta Sincro & Sincro Factory two stroke models 125-300cc engine sizes for years 2026+.
Part # BT-5 Technical Data:
PATENT PENDING
Body-anodized 6061-T6 aluminum
Sealing/Fitting- (2X) size 122 Bunna-N O-rings
Weight- 39 grams/1.4 oz