Dielectric Grease

Dielectric Grease | Vintage Honda Electrical Connectors and Terminals

Silicone-based dielectric grease for the electrical connectors, battery terminals, bulb sockets, and spark plug boots on your vintage Honda. A dab on a new or freshly cleaned connection helps keep corrosion off in the future.

Why You Need This

Corrosion at a connector or terminal is a common cause of poor electrical contact, and on a vintage Honda those connections have often gone untouched for decades. Dielectric grease, often called tune-up grease or silicone grease, works as a lubricant, sealant, insulator, and protector. It helps prevent stubborn, corroded connectors, shields your electrical system from water and moisture, and keeps rubber boots from drying and cracking.

It's what we use on the electrical connectors on our own bikes. In our CT90 regulator / rectifier install video, the terminals get a little dielectric grease before they're connected.

Specifications

Note: Keep it out of the brake hydraulics. Use brake fluid to lubricate a caliper piston, because nothing other than brake fluid belongs in the hydraulic system.

How to Use It

Difficulty: Beginner

1. Start with a clean connection. A badly corroded bullet terminal is best cut off and replaced with a new one crimped on. Switch contacts can be taken apart, sanded clean, and wiped free of residue.
2. Apply a dab of grease to the terminals or the new or freshly cleaned connection.
3. Plug the connection together or reassemble the part. A dab will do the trick, so don't let the grease get in the way of a tight connection. Less is more.

Plastic multi-pin connectors: Along with a dab of dielectric grease, solder the terminals and heat-shrink each wire up to where it enters the connector. That makes the connection quite bulletproof.

Frequently Asked Questions

Where should I use dielectric grease on my Honda?

Use it on bullet connectors and plastic multi-pin connectors, battery terminals, spark plug boots, switch contacts after you clean them, regulator / rectifier terminals, bulb bases so the bulb doesn't rust into its socket, fuse blades, flasher relay prongs, horn contacts, and brake light switch connectors.

Will it help a loose bullet connector?

Bullet terminals, both the male and female sides, sometimes run a bit large or a bit small. Tweak the female side to open it up or squeeze it down until it fits the male bullet properly, and a little dielectric grease will help that connection in the future. If the terminal is in bad shape, strip a little wire and crimp on a new one.

Can I use it on rubber parts?

Yes. It lubricates plastic and rubber parts and keeps rubber boots from drying and cracking. A little silicone grease inside the rubber intake boots can also help the carburetors slide in.

Can I use it on my brakes?

Not in the hydraulic system. Use brake fluid as the lubricant when you install a caliper piston, because you don't want anything other than brake fluid in the hydraulic system once everything is installed.

How much should I use?

A dab. Apply just enough to coat the connection without getting in the way of tight contact between the electrical components. Less is more.

You Might Also Need

• Bullet Electrical Connector Terminal Assortment — male, female, and double-female bullet terminals with rubber covers, for replacing corroded bullets
• Bullet Style Electrical Terminal Crimping Tool — the open-barrel crimper for new bullet and spade terminals
• 6-Pin Plastic Wiring Harness Connector — male and female housings with brass spade terminals; also in 3-pin and 4-pin
• Vintage Honda Motorcycle Electrical Connector and Repair Kit — bullet and spade terminals, plastic connectors, heat shrink, and wire in one kit
• AGM Motorcycle Battery — sealed replacement battery; a dab on the terminals helps keep corrosion off
• Incandescent Instrument Gauge Bulbs (5-Pack) — a small dab on each bulb base before it goes in

Last updated: October 2026