Factory Style Mirror (M8 Threads) | Honda CT90 / Trail 90 (K0-K5) / CB100 / CB125

Factory Style Mirror (M8 Threads) | Honda CT90 / Trail 90 (K0-K5) / CB100 / CB125

A cracked, hazed, or snapped-off mirror is an easy fix, as long as you get the right thread. These are chrome, factory-style round mirrors with the smaller M8 stem the early CT90, CB100, and CB125 used, sold as a pair.

Why You Need This

The original mirrors on these bikes fog over, crack, or shear off in a tip-over, and a clear mirror is worth having on anything you actually ride. These chrome round replacements thread into the factory mount and give you back a solid, clear view.

The one thing to get right is the thread size. The early small-bore Hondas used an 8 mm mount, while later bikes switched to a 10 mm mount. The easiest way to tell them apart: the 8 mm mounts are drilled and tapped into the upper half of the handlebar switch boxes, and the 10 mm mounts go through the flat of the lever perch. If yours is the 10 mm size, you want our M10 factory-style mirror instead.

Specifications

Model-Specific Notes

• Check your mount before ordering: The small Honda singles went through a thread change over these years. Look at where the mirror threads in — drilled into the upper switch box is the 8 mm mount this mirror fits; drilled through the lever perch is the 10 mm mount. When in doubt, back your old mirror out and measure the thread.
• SL100 / SL125: If you have one of the small scramblers, double-check your mount size before ordering, since these sit right at the 8 mm / 10 mm changeover.

Installation

Difficulty: Beginner

Tools needed: A wrench to fit the lock nut.

1. Thread the old mirror out of the switch-box mount, counterclockwise.
2. Put a little anti-seize on the new mirror's threads — the mounting bosses are soft aluminum and seize up over time.
3. Thread the new mirror in and snug the lock nut. Don't over-tighten; the bosses strip easily.
4. Sit on the bike, set the mirror where you want it, and lock it down.

Frequently Asked Questions

How do I know if I need the M8 or M10 mirror?

Look at where the mount is drilled. The 8 mm mount is tapped into the upper half of the handlebar switch box; the 10 mm mount goes through the flat part of the lever perch. If you can, back the old mirror out and measure the thread to be sure. This mirror is the 8 mm version.

Are these sold as a pair?

Yes. Each order includes two mirrors.

My mirror snapped off in a drop. Is this the replacement?

If your bike is an early CT90, CB100, or CB125 with the 8 mm mount, yes. Check your remaining mount to confirm the thread, then order the pair.

You Might Also Need

• Factory Style Mirror (M10 Threads) | Honda CT90 K6 & Up — the 10 mm version for later bikes
• Anti-Seize Lubricant — keep the threads from seizing in the aluminum mount

Last updated: July 2026