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A fellow rider just picked up an old mountain bike which has some rust and plenty of gunk in the gears to wash out. He intends to use gasoline to clean the entire bike.

This is the first I ever heard of using gas to clean the chain, gears, spokes, pedals, derailleur. Does it work? Save time? It stands to reason it might cut through the grease but can it restore any luster to rusty components?

If no --> the materials & methods YOU use to clean/restore bikes would be appreciated.

also Is there anyway to get rust off the wheels, handlebars, nuts/bolts etc?

Please do not use product names, company names or backlinks in your answer; this is not an invitation for spam.

NOTE "Water, soap, elbow-grease, oil & rubber-protectant" is not an acceptable answer - looking for insight not a statement of the obvious.

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    note that gasoline is a mixture of petrochemicals, ranging from mildly toxic to acutely poisonous. You should avoid inhaling the fumes or getting it on your skin. If you want cheap organic solvents, kerosene is better and it's got fewer volatiles and the poisonous fractions don't soak through your skin as fast. But you're much better off with a proper degreaser.
    – Móż
    Oct 30, 2016 at 7:43
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    Kerosene is much better, it's what we used in my motor mech apprenticeship
    – Kilisi
    Oct 30, 2016 at 8:06
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    It needs to be emphasized that gasoline/petrol is extremely flammable, much more dangerous than most of the other alternative solvents. It should only be used "out of doors" (or at least in a garage with the vehicle door open). And, contrary to what's stated elsewhere here, it's critical to keep gasoline away from any rubber components, and some plastics. Even the fumes are damaging. Oct 30, 2016 at 12:33
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    And note that all gasoline will do is dissolve hardened grease and certain poorly-chosen (DIYer-applied) paints. It's not going to do anything for rust, and is apt to make some paints duller. Oct 30, 2016 at 12:35
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    Finally, understand that any bearings soaked in gasoline need to be properly relubricated. If pedals are soaked in it, eg, they need to be disassembled and the bearings re-greased. Oct 30, 2016 at 12:36

7 Answers 7

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Gasoline aka petrol, is a volatile fluid that will dissolve grease and oils. It will penetrate, soften, and loosen impacted and congealed dirt and dust.

Petrol / Gasoline will NOT fix your rust, nor remove your rust. It will not restore chrome.

Petrol is not terrible for rubber parts, but I wouldn't leave them soaking in the fluid.

The best use for petrol is to clean your parts, before doing a close inspection to decide whether they are serviceable still, or need replacement.

Downside for petrol is that right now its NZ $1.97/litre in my country (approx US $5.36/US Liquid Gallon) and that adds up. You can't reuse the dirty petrol for anything, and the grease won't settle out so it can't even be decanted.

Petrol is also hard on your skin, so wear gloves, and clean up immediately afterward. Moisturising your hands before starting is surprisingly good protection too.


Rust

Rust is oxidised iron, which comes from steel being exposed. Often appears on friction points like chainring teeth, and anywhere that the paint has been damaged letting fresh oxygen to the steel.

There are options:

  • Leave it alone. This uglifies your bike and makes it less desirable to thieves, as long as its still mechanically and structurally sound.
  • Paint over it - this is a very short-term fix and will not last more than a month before the new paint is bubbling off.
  • Remove the rust then paint it - this is elbow work with a file and sandpaper, or some motorised tool doing the same thing. You MUST paint the surface within a few hours, else the virgin steel starts to rust again.
  • Treat the rust - There are many rust treatments which transform red rust into a more stable black oxide of iron. Most contain Phosphoric Acid and require PPE. The fumes are something else! Once the rust has blackened and dried, you can sand and overpaint.

Petrol would be used as a degreaser on the rust before sanding. Turpentine would be similar, but that's even more expensive than petrol.

Have a look at Suggestions for removal of old chrome? where I am doing something similar to some handlebars. That question will be updated as progress continues.

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    Wondering whether paraffin will do the same job as petrol. It's been used in the automotive industry for a long time too. As mentioned above though, it'll do nothing for the rust. I personally use biodegradable degreasers that are normally bike-specific. Many smell very strongly of lemon. If there's a lot to shift, make sure you use gloves or your hands will get very dry and itchy. Not good to absorb this stuff either.
    – Chris
    Oct 30, 2016 at 7:09
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    You can leave the grot to settle and re-use the petrol for cleaning more parts, though. Commercial kero baths have a settling tank plus a filter, for example. But that is strictly "cheap or desperate" territory, where you're trading years of life later for saving money now.
    – Móż
    Oct 30, 2016 at 7:44
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    @Chris - to clarify, you're referring to the British "paraffin", which is known as kerosene in the USA, right? In the USA, "paraffin" typically refers to paraffin wax which doesn't seem like it would be an effective cleaner, but some do use paraffin wax as a chain lube
    – Johnny
    Oct 30, 2016 at 19:36
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    Actually since it's all basically a petrochemical then it's a solvent just the same. Petrol is rarely used as a solvent in the UK except in car accidents when is pours out of the tank and dissolves the road.
    – Chris
    Oct 30, 2016 at 20:46
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    @Criggie excellent & useful info. +1 for thorough discussion of rust. In short we've got a "yes, with a sort of, kind of and a no." I marked your answer as sufficient; but since I did not anticipate the discussion my OP is creating, plz feel free to leave your answer/comment. Thx SE Bike OCD support group!!!! xD. FYI - gas costs ~ $US 2.35/gal in LA, CA @ time of this writing 11/16.
    – Tapper7
    Nov 5, 2016 at 14:32
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Gasoline does work for cleaning parts. But it's also extremely toxic and flammable, and may damage rubber or plastic parts (depending on the parts). So don't bother, just use degreaser. (If you want to get the strong stuff, go to an auto parts store. If you want to get massive quantities of the strong stuff, go to a janitorial supply or restaurant supply store.)

Also, don't go too crazy when cleaning your chain. You don't want to remove all the grease, you just want to get the dirt off the surface.

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  • yep, made that mistake before. One time I cleaned by chain with degreaser and a wire brush and it was squeaking for a week no matter how much chain lube I put on it. Ended up having to soak it in a bag of chain oil to get it fixed. Nov 15, 2020 at 19:09
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Gasoline may work as a degreaser, meaning it may improve the looks of your metal by removing the superficial coat of oil/grease.

I would not recommend the use of gasoline, because it will have additives that are intended for motor engines, and you do not know the effect they will have in your parts. Secondly, I would not recommend using it in a chain, because manufacturers often discourage usage of kerosene in them, which is similar to gasoline (may damage chain parts).

That being said, it is important to remember that gasoline, as a strong non-polar solvent, may easily damage rubber, plastic parts, paint clear coat, etc... Something to definitely keep away from most parts of your bike.

You may use a standard citrus degreaser, which is sold by major bike maintenance companies. As they are water based, you should remove it after with a dry cloth. They will not rust your parts, unless you leave the part soaking for a couple of days in it.

If you have rust spots, the recommended solution is to replace the part, as rust removal techniques are somewhat limited. If it is, for example, a rusted chain, I would definitely recommend the replacement of the part.

If you have minor spots of rust in your frame (assuming it is a steel frame), you could use some sprays for rust. They convert iron oxide to a more stable form, and it may stop the process right away.

However, if the rust area is large enough to compromise structural integrity, I would replace the the part. It is better to spend money in the part, than in the hospital after the part fails.

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  • thx for the info. the bike I ride is flawless; prev. owner & I both kept/keep it indoors. here in Los Angeles the roads don't get salted; a collector-friendly climate for cars/bikes. The question refers to a "beater" we came across (has miniscule rust spots in the areas you'd expect; nothing "structural" we'd not keep or ride a bike in THAT bad a condition! could be a decent bike with some part swaps)....& I was wondering if materials engineers had come across a rust removal method I haven't...I've bought a few "rust removers" they don't clean/restore as advertised.
    – Tapper7
    Nov 5, 2016 at 14:57
  • @Tapper7 of course they don't work effortlessly... "spray on, wait, hose off" is one of the biggest crocks of advertising. You generally get better results with added effort.
    – Criggie
    Nov 9, 2016 at 6:15
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It needs to be emphasized that gasoline/petrol is extremely flammable, much more dangerous than most of the other alternative solvents. It should only be used "out of doors", or at least in a garage with the vehicle door open and no nearby source of ignition such as a water heater. Even flicking on a light switch in a gasoline-fumed garage could be hazardous.

Gasoline is also quite toxic. While many of us have, in our youth, survived using gasoline for cleaning bike and automotive parts, eventually the inhaled fumes will affect your liver. If your liver is reasonably healthy you'll likely not have a noticeable problem, but if you have liver disease already then repeated exposure could "push you over the edge" to liver failure. Plus there are problems you can have with your skin, eyes, lungs, and kidneys.

And, contrary to what's stated elsewhere here, it's critical to keep gasoline away from any rubber components, and some plastics. Even the fumes are damaging. While most tires and plastic parts will survive a brief exposure, I have seen rubber and plastic bits instantly dissolve in gasoline, and, in particular, "gumwall" tires are highly susceptible to damage if splashed gasoline is allowed to sit on the sidewall for more than a few seconds.

As to it's effectiveness, note that all gasoline will do is dissolve hardened grease and certain poorly-chosen (DIYer-applied) paints. It's not going to do anything for rust, and is apt to make some paints duller. And other solvents (such as one might buy at an auto parts place) are just as effective and at least somewhat safer.

Regarding the use of any petroleum-based solvent, understand that any bearings soaked in it need to be properly relubricated. If pedals are soaked in a solvent, eg, they need to be disassembled and the bearings re-greased.

For rust, I have had some modest luck using an oxalic acid solution (or "Barkeeper's Friend" scouring powder which contains oxalic acid) to remove light rust from chromed surfaces and even brake cables. The oxalic acid solution is available from paint stores as "wood bleach".

For rusted brake cables (a common problem with the bikes we rehab for charity) I dribble the oxalic acid solution down the cable into the housing, and usually a frozen cable breaks free within 5 minutes or so. (I've devised a scheme, using some rubber tubing, for forcing liquid into housings that are really tight at the ends.)

For, eg, chrome fenders with bits of rust showing through, scrubbing with a damp cloth and Barkeeper's Friend generally improves appearance significantly. (I suppose it would be good to follow up with a waxing, to prevent further rust, but we don't usually go that far.) For rusty bolts, to improve their appearance, I treat them first with a spray of the oxalic acid solution, then dry and oil the item to prevent the rust from reappearing.

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No, gasoline is completely useless to remove rust. Rust is an inorganic compound, which is neither dissolved nor modified by hydrocarbons. There are a ton of commercial products to remove rust, as you don't want any product suggestions, go and search yourself.

Gasoline is only good as a de-greaser, but: gasoline contains benzene. Benzene is extremely toxic and has been proven to cause cancer in humans a long time ago (timeline here: https://www.publicintegrity.org/2014/12/04/16320/benzene-and-worker-cancers-american-tragedy).

Not worth to risk of brain damage, leukemia or liver cancer as there are plenty of other alternatives available. To de-grease, use detergent and hot water (pressure washer, but be careful bearings don't get wet), to get rid of rust, use commercial products.

There is no chemical agent that will remove rust and leave a good surface by itself, all require mechanical cleaning, i.e. a wire brush. You can also have the parts sand-blasted for little money. There are a lot of different blasting agents, and some leave a nice and shiny surface.

As Mike also pointed out, gasoline is also extremely flammable. This is hard to believe when you haven't experienced it yourself.

Here is a video of a guy who nearly died

lighting a fire with gasoline. This is probably a similar amount what you would use to clean a bike. The gasoline vapors are very dense and flow like water, they can travel quite a distance to an ignition source. One spark and you are a human torch.

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    FYI phosphoric acid does a good job of chemically changing red rust to black iron oxide. Personally I sand the rust down before so there's less to convert, After conversion what was rust is a black metallic blob that is not a good finish either, but can also be sanded and filed.
    – Criggie
    Nov 8, 2016 at 8:11
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    Good point. I've tried that a while ago and in contrast to gasoline it works. Here is a video what finish one can expect with phosphoric acid. youtube.com/watch?v=J7pIGZ2ufhk
    – bikerjoe
    Nov 9, 2016 at 2:12
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My friend tried a very powerfull thing - citric acid, such as in lemons and limes, which can dissolve rust. Start by pouring some citric acid onto a sponge, steel wool pad or rag. We used a thin compressed steel wool, but for this purpose may come any solid material. Simply rub or scrub the rust off the bike. You can also clean the chain, but you need to remove carefully all traces of acid. Acid used here at your own risk. After you have scrubbed the bike clean, wipe it down with a towel or rag to get off any extra residue, because letting citric acid sit too long can lead to damaged metal. it is very important to dry thoroughly all parts of the bike. Take a dry paper towel or old rag and wipe everything dry several times. On the rag must remain grease and rust.Than to provide an efficient work of your bike, lubricate all moving parts. Inject grease during rotation of the wheel or apply a little gel lubricant to a paper towel and gently wipe the chain. After some time make sure that no rust left on and you can paint it with a special spray paint. We tried and it worked!

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DO NOT USE GASOLINE FOR ITS SOLVENT PROPERTIES Gasoline is highly flammable. An illustration why it shouldn't be used came at pizza one night after a club bike ride. A ride coordinator said, "I've got to go lead a ride for so-and-so on Saturday. He was cleaning his chain with gasoline in the garage and burned it down."

I really like using soap and water for ordinary grime on the frame and rims, followed by drying it all off. I favor odorless mineral spirits for cleaning parts like chain and bearings -- in a well-ventilated space. And there is this cotton wadding impregnated with some kind of polishing substance, which is good for restoring the shine to bare metal. One brand name is Dura-Glit.

Good luck -- and don't burn your house down.

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  • Welcome to bicycles.SE @ichabod, and thanks for a well-written answer. We recommend all new users take the tour, and it can't hurt to read about how to answer either. Again, welcome, and we'll look forward to reading more from you in the future.
    – rclocher3
    Nov 11, 2016 at 18:16
  • Everything has some level of risk. If someone was dumb enough to use petrol / gasoline / benzine near a source of ignition, (pilot light, lit ciggy) then they were stupid.
    – Criggie
    Nov 11, 2016 at 20:51

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