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A bit of history: the grooves on the spindle are partially destroyed/skewed by cycling with a loose crank, so I applied a lot of force to a hexdriver to get the crank arm on. Now, it would be quite hard, if possible, to disassemble it. I got the bicycle on a garage sale for a price of two cups of coffee.

The crankset began to creak.

Can I get a grease on it without disassembling the crank set?

I tried leaving the bike laying on a side and pouring WD-40 on the side of crankset. It helped for some time, because it's fluid enough, but WD-40 is not a proper grease; it needs to be reapplied once in few days, and then it makes it worse because it also acted as a solvent for the original grease.

Maybe there's a grease I can heat up to about 80°C to make it fluid enough to get into the crankset and curdle inside?

I don't have access to special the tools like crank arm remover, or whatever else could be needed. I only have generic wrenches, screwdrivers and hexdrivers.

I would highly appreciate NOT receiving these answers/comments:

  • invest time and money -- buy proper tools and disassemble it. I recognize this is probably the right answer; but it's just a creak of a bicycle that costs me two cups of coffee.
  • replace the whole crankset. I'm pretty sure I can get a few more hundred miles out of it and replace it later. Plus, it costs as much as a new (used) bicycle - more than this whole one, - plus the time and tools to install.
  • take it to a bicycle shop. I live in a very expensive area; it will probably cost me more than buying a new bicycle.
  • WD-40 is not a (proper) grease, use the right one.

Thank you.

  • It doesn’t matter how expensive your bike is, all that matters is that you maintain it properly. – Swifty Apr 26 at 18:02
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    What I would do is get some regular auto grease (the thick yucky stuff), lay the bike on its side, smear the grease around the gap between the rotating piece and the fixed piece, and then try to press the grease into the gap. The exact technique is going to depend on the details of your setup, and it will be hard to get behind the chainrings (if you can't somehow remove them), but the procedure can be modestly effective (though nowhere as good as disassembling and coating the parts with grease). – Daniel R Hicks Apr 26 at 18:03
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    Does the bike have a cartridge BB or is it loose balls in a cup and cone race? – Criggie Apr 26 at 23:22
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    It's a sealed cartridge. – Victor Sergienko Apr 26 at 23:29
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    As an interim solution a proper lubricant like a MoS2 might help a little more than WD40. Heating a grease won't do. A good grease doesn't flow when it gets a little warm. Otherwise it'd run out in summer. Getting the hole BB spindle hot enough will destroy too much else on the bike. Criggie's answer is the way to fix it. Even though it's work. – gschenk Apr 27 at 16:08
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Given the parameters of the question...

The goal is to get a better lubricant than WD-40 into the bottom bracket.

Two suggestions:

  • Do the "leaving the bike lying on a side" thing and use motor oil. It's much better than WD-40 but not as good as grease.
  • I have a can of spray lithium grease. It's thicker than oil and you might be able to spray something like that into the bottom bracket between the axle and the cup.

Heating grease changes it's characteristics. My thought is I'd rather use motor oil than heated grease.

Keep your eye out for a different two-cups-of-coffee bike from a garage sale.

  • Thanks! Pushing it in with a pressured air may work. Otherwise, I will do it properly, eventually. – Victor Sergienko Apr 26 at 21:39
  • Heating the oil to 100ºC shouldn't harm anything - it's the normal motor oil operation temperature. It could rather harm the paint, but I doubt that as well; exposing a black bicycle to the sun for an hour would heat it the same. – Victor Sergienko Apr 26 at 21:40
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    Heath the oil won't help. The feew drops that get through creaks will cool down and not get where it's needed. You'd have to heat the BB so that the inside is git enough. Then hope for capillary action to get a little where you need it. Tried such things before. Just a mess. Get a solid lube [en.m.wikipedia.org/wiki/Dry_lubricant ]in a thin oil solution instead. Use that often to deposit enough lube particles. – gschenk Apr 27 at 16:12
  • Tested it for 2 weeks. A can of lithium grease spray helped, thanks. Probably not due to pressured air, but due to the time I let it leak through, laying the bike on its side. This cost around 1/30 of the full disassembly and replacement, not counting time invested, and will let the bike run for some more years. – Victor Sergienko Jun 7 at 23:41
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I'm going to offer the contrary answer - why not fix it properly?

Summary: Your spindle/crank interface is damaged, so the crank has been forced onto the spindle and is now at a high state of torque. Its confirmed that the spindle is damaged and likely that the crank arm is now damaged as a result. And the rest of the bike is OK.

So the worst case is that your BB needs replacing, and that the crank arm is damaged enough to need replacing too.

Replacing the BB with a nice new cartridge will give you a new spindle/axle, and it will give you a much better pedal feel. You will have to match the new spindle to your crank's interface, being square taper or octalink or whatever.

Shimano UN26 BB cartridge, square taper

You won't know if the crank's a writeoff till you get it off. So pick a time when you don't need the bike for a bit and can work on it.


Consider that had you changed the BB for a new cartridge, the crank arm would have gone on easier and not been damaged. By cramming it back together, you've made your problem worse. Do it right sooner, not postpone till later.

Just cos the bike had an initial cost to you of 2x coffees, doesn't mean its junk. You could look for another donor bike to salvage some cranks, or check Ebay/craigslist/gumtree/etc.

Note that your left and right crank don't need to match, they just need the same fittings and same overall length.

As for getting the current one off - leverage will help. If the bolt shears then the stub will be in the BB spindle/axle which is trash anyway, and the new one will come with replacement bolts.

You don't need a LBS for this - its dirty but its not hard. The only tool that will be odd is the fitting for the ends of the cartridge.

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    Depending on your location, there are bike cooperatives around the world that can help you with access to tools, and advice in person. They often have parts available should your crank arm prove unserviceable once removed. – Criggie Apr 26 at 23:34
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No.

It seems that you have already done your homework and know why you don't want to fix things properly or why WD-40 doesn't really work. But you had to ask, didn't you.

  • Thanks. Sure, I wanted to get a confirmation and more ideas. I will accept one of the answers depending on whether a spray grease works. – Victor Sergienko Apr 26 at 21:35
  • From the description it sounds like the creaking may also be from crank-spindle interface. – ojs Apr 26 at 21:39
  • Thanks! I think I tried rotating it with a single pedal, on both sides, but I'll test again. – Victor Sergienko Apr 26 at 21:41

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