The SINZ SL-1 / V2 Stem Lock (1-1/8", Black) is a heavy-duty headset compression system designed primarily for BMX racing and freestyle bikes. It replaces the traditional star nut and top cap setup, passing completely through the fork's steerer tube to mechanically clamp the stem to the bottom of the fork. This innovative design prevents your headset from coming loose under heavy impacts.

Key Product Details & Specifications

• Brand & Model: SINZ Products SL-1 / V2 Stem Lock
• Steerer Tube Diameter: 1-1/8" (standard oversized fork steerer size)
• Adjustable Length Range: 175mm to 270mm (handles short BMX race tubes up to tall pro configurations)
• Weight: 83 grams (for the 1-1/8" variant)
• Material: High-strength aluminum alloy top and bottom caps with a steel tensioning rod
• Colour: Black

Core Functional Features

• Star Nut Replacement:
  Eliminates the risk of a traditional star nut slipping upward inside the alloy or chromoly steerer tube during harsh landings.
• Safety Fail-Safe:
  Acts as a critical structural backup. If your aluminum fork steerer tube suffers a catastrophic fracture, the through-rod design can help keep the front wheel and fork legs physically connected to the frame.
• Clean Tool Access:
  Features an internal tensioning mechanism that tightens from either the top or bottom cap using standard Allen wrenches, ensuring uniform headset preload.

This system is ideal for riders seeking enhanced durability and reliability for their BMX or freestyle bikes.