Left Pedal Thread Inserts, 10-Pack

The Left Pedal Thread Insert 1695.4A is the part that turns a stripped left-hand pedal hole back into a working pedal thread. The insert is a sleeve with two thread profiles: an outer thread that engages the freshly cut hole left by the 1695.1AL Left Reaming Tap, and an inner thread that matches the standard 9/16" × 20 TPI left-hand pedal thread.

Once the insert is installed and the thread locker has cured, the crank arm takes any standard left-hand bicycle pedal. The customer rides away on the same crank they came in with.

The complete rescue workflow

A successful pedal-thread rescue is four steps:

1. Ream the failed thread. Use the 1695.1AL Left Reaming Tap on the Handle for Pedal Taps 1695/4BI. The reaming portion cuts the failed thread away and enlarges the hole; the thread-cutting portion cuts a new thread sized for the insert.

2. Apply thread locker to the insert. A strong thread locker; typically a green or red; gives the insert the bonding it needs to stay put under repeated pedal removal-and-install cycles. Apply to the outer thread of the insert, not the inner thread.

3. Install the insert into the crank arm. Thread it in by hand until it bottoms out. Don't over-torque; the insert should sit flush with the crank face.

4. Let the thread locker cure. Follow the locker manufacturer's cure time (typically 24 hours for a strong cure under no load). Then the pedal can be installed normally.

Why a pedal-specific insert vs. a Heli-Coil

A generic Heli-Coil-style spring insert engages the host thread on its outer profile and accepts a fastener on its inner profile, but the spring's coils flex slightly under load. For a pedal; which sees high cyclic load, vibration, and the regular install-and-remove cycle; a solid sleeve insert holds the thread profile more consistently than a spring insert. The 1695.4A is a solid sleeve, sized specifically for the 9/16" × 20 TPI left-hand pedal thread.

What's in the pack

10 inserts per pack. That's enough for several rescue jobs; the inserts don't go stale on a shelf, and the working-shop economics of pedal rescue favor stocking the consumable in volume.

Specs

• Left-hand thread, 9/16" × 20 TPI inner
• Outer thread sized for 1695.1AL Left Reaming Tap
• 10 inserts per pack
• Article number: 1695.4A (left-hand variant)

Built in Zreče, Slovenia

Unior has been forging hand tools in Zreče since 1919, and sponsors professional road and mountain-bike race teams. The 1695.4A insert is a Unior-specific design that matches the cut profile of the 1695.1AL reaming tap. Substituting a generic thread insert (Heli-Coil, Time-Sert) will not fit; the thread profile is different.

Pro tip from our mechanics

A shop that does pedal rescue gets known for it. Customers bring in their cranks expecting to hear about a replacement; they leave with the same crank and a $60 invoice instead of a $200 one. Our workshop hand tools guide covers the full pedal-rescue workflow and the rest of the workshop hand-tool layer: Workshop hand tools every bike shop needs →

FAQ

Why are there 10 inserts in the pack — do I need all of them for one repair? One rescue uses one insert. The 1695.4A ships as a 10-piece set because it's a workshop consumable: the inserts don't age on the shelf, and a shop that does pedal-thread rescue goes through them. The price is for all ten inserts, not one.

How do I know I need the left insert and not the right one? The left crank arm uses a reverse (left-hand) pedal thread, so it needs this 1695.4A left insert with its 9/16" x 20 TPI left-hand inner thread. The right crank arm takes the 1695.3A right insert. Installing the wrong hand will not accept your pedal.

Do I need the 1695.1AL reaming tap to install these inserts? Yes. The insert's outer 5/8" x 24 TPI left-hand thread is sized to the seat the 1695.1AL left reaming tap cuts into the crank arm. A generic thread insert or a hole that hasn't been tapped to this profile will not hold the insert.

Which pedals fit after the insert is installed? Any standard left bicycle pedal with the 9/16" x 20 TPI left-hand thread — that covers virtually all modern two- and three-piece cranks. Let the thread locker cure per its manufacturer's instructions before installing the pedal at full torque.