The can sputters empty with the chain half-lubed, or you're three days into a trip and the chain is squeaking. What in the garage — or the gas station — actually works on a chain? Ranked honestly, from legitimate to chain-killer.
Legitimate stand-ins: gear oil and engine oil
Heavy gear oil (80W-90) is the classic — it's what riders lubed chains with for decades before aerosols, and it genuinely lubricates rollers and seals. Clean engine oil works on the same logic, a little thinner. Apply either sparingly to the inside run with a rag or brush (standard technique), wipe the excess, and accept the trade: both fling more and attract dirt faster than dedicated lube, so they're a bridge to the next proper clean-and-lube, not a new system — unless you adopt the old-school clean-constantly discipline that made gear oil work in the first place (the comparison covers that lifestyle).
Emergency-only: WD-40 and its cousins
Light penetrating oils displace water and leave a thin, short-lived film. As protection for a chain that just got rained on with nothing else available, better than nothing; as lubrication for riding, nearly nothing — the film is gone in miles (the full WD-40 verdict). Use it to prevent overnight rust, then get real lube on the chain before real miles.
Do not use
Cooking oils oxidize into varnish and gum — a chain dressed in olive oil ends up sticky, grit-caked, and harder to clean than a neglected one. Thick grease can't penetrate roller clearances; it armor-coats the outside, collects every particle of dust, and starves the actual wear surfaces. Brake fluid, penetrating solvents, diesel: solvents and hydraulic fluids aren't lubricants, and some attack O-rings (the chemistry list).
Dry is the worst option
The reason makeshift oil beats purity: metal-on-metal running wears rollers measurably per mile and cooks seals (the heat spiral). If the choice is engine oil or nothing, it's engine oil, every time.
Next time insurance
The fix for this whole article is a backup: a small travel can in the tail bag (the touring kit) or just two cans on the garage shelf, replaced when the first dies. Chain lube is the cheapest consumable on the bike — running out should be a once-per-riding-career event.
Quick answers
What can I use instead of chain lube?
In a pinch: gear oil (80W-90) or clean engine oil applied lightly to the inside run. Both lubricate genuinely, just fling and attract dirt faster than dedicated lube — clean and re-lube properly soon after.
Can I use cooking oil or grease on a chain?
No. Vegetable oils oxidize into gum, and thick grease can't penetrate the rollers — it coats the outside, catches grit, and starves the parts that matter.
Is riding with a dry chain worse than using engine oil?
Yes. A light coat of engine or gear oil beats bone-dry metal every time. Dry running wears rollers fast; the makeshift oil just needs replacing with real lube promptly.
Homemade chain lube: the recipes people actually mix
The DIY searches keep growing, so here's the honest rundown of what garage chemists mix. Chainsaw bar oil thinned with a little solvent — the solvent carries it into the links, evaporates, and leaves tacky oil behind; the most defensible homemade recipe because bar oil is designed to cling. Gear oil, straight or thinned — lubricates fine, flings hard, collects grit; the budget dirt-bike classic with a cleaning tax. Motor oil — better than a dry chain, worse than everything else; fling city. The DIY wax pot (paraffin melted with a little oil, chain dipped) — genuinely effective and clean-running, but it's a stove project with hot-wax hazards, and modern o-ring chains don't benefit inside the links the way old plain chains did; wax the outside, respect the o-rings. The one universal rule: never anything with grit-attracting stickiness on a dirty chain — homemade lube over grime just makes grinding paste with extra steps. Clean first, always: that's the 60-second job.