Narhay

I have a brass wire wheel on a drill and use that to knock off the black stuff that builds up on chainrings. It also allows me to get into the tooth grooves.

willydstyle

OK, an update. I started going at my crank with simple green, and it didn't help much. I switched to Formula 710 and a bit of steel wool and got these results:

Henry III

I used to let stuff soak in Simple Green but it it sits too long and there's any type of screen printing you can kiss that goodbye and some anodization loses it's luster like on Campag parts. Also painted parts lose their shine and get a cloudy appearance.

Narhay

I've resigned myself to having to disassemble chainrings. Try the wire wheel, it will knock off the remainder of that black stuff.

eschlwc

some of the bikes i buy are so disgusting with the worst crud this cruel world emits i wonder why the owner bought the bike in the first place. i haven't any idea how the bikes could provide any happiness in their sad, forgotten state.

the worst of it is always the freewheel and rear derailleur pulleys. i take them off and let them soak in a coffee can of mineral spirits for an hour.

the freewheel then gets easily cleaned by hand. it then soaks in a motor oil before drying.

the rd is fully overhauled.

chain rings are unbolted and either just washed (if i'm lucky) or deanodized (with oven cleaner) and polished with sandpaper (if i'm unlucky).

Prowler 

Finally. For some reason it took 30 posts before someone mentioned mineral spirits. I use MS for all kinds of gunk; cheap and it handles it all. I've no reason to think it damages paint or anodizing or screen print or decals. Mostly I'm using it sparingly (not slobbered) and I keep a jigger or two in a cat food can for soaking screws, bearing cages, cones and other metal bits. For really awful dried gunk I'll scrape that off with a dull knife first but I could just let it soak but it takes longer. I use an old tooth brush dampened with MS on alot of spots - metal bits, components and even crannies of the frame. I also keep a few small pieces of Formica type laminate around - they make good scrapers. Better than plastic but softer than steel.

I keep a couple of inches of MS in an old plastic milk jug for cleaning chains. After it gets awful looking just let it sit for a couple of weeks and the filth just settles out to the bottom and you decant the clean MS off and keep going.

Some folks worry about MS being flamable. Well, no more so than the gasoline, kerosene, alcohol, carb cleaner, laquer thinner, motor oil and all that other stuff I keep out in the detached garage where my shop is. Risks of having a multi purpose shop.

Michael Angelo 

+1 for mineral spirits. One should also be aware that any kind of de-greaser will wash out bearings. Including hub and Bottom bracket bearings. The LBS's love for you to use simple green, carb cleaner, or any other nasty solvent. That way they can sell you new parts......


I use mineral spirits, being careful to keep in away from the bearing areas. For the rest of the bike I use dawn soap and water, followed by a good wax job....done!!

old's'cool

Um, yeah... anything that is good at taking off crud is excellent at taking off oil and grease. Anything that I want to clean thoroughly with solvent I first disassemble completely; and of course re-apply the appropriate lubricant(s) during re-assembly. Chains excepted, but that is another discussion!!

RandolphCarter

^^^ This ^^^

Since any bike I'm dragging home is usually a total basket case, I quickly learned to appreciate the gunk-dissolving value of mineral spirits.

Please note there is a difference between "I just dragged home an old bike I pulled out of a dumpster, and I need to clean off 35+ years of accumulated crud" and "I've been riding my bike for 3-4 months since the last tuneup and I've noticed a minor amount of gunk building up on the freewheel". I'm focusing on the first scenario.

Here's what I usually do:

1) Disassemble. I don't try to clean heavily soiled parts while they are mounted. You won't get all the crud, and you'll probably leave residue in places you can't reach. Further breakdown is probably needed once you get the parts off of the frame, like Pastor Bob outlined with his freewheel overhaul. This will also allow you to determine if the parts in question are even worth time and effort.

2) Initial de-gunking. Scrape the crud off with a variety of tools. I have a horribly ugly collection of plastic paint scrapers, putty knives, screwdrivers, and dental picks I use for loosening/scraping. This is followed by a quick wipedown with a paper towel moistened with mineral spirits.

3) Soak! Like others pointed out, put the parts in a mineral spirits bath and let them marinate. I have several containers I use for this. One will have the parts soaking in it, and it will be spirits I've used before. the other I will clean out and use either fresh spirits or reclaimed spirits using Prowler's settle/pour-off method. So soak the parts, swish them around, the great majority of the crap should dissolve or easily rub off. Use an old toothbrush to scrub away the gunk. Blot dry with a paper towel, and then rinse in the clean spirits. Let dry on paper towels. Any steel parts should immediately get a thin coating of lube or oil to prevent rusting.

Also, when I'm working on larger alloy parts like chainrings and rims (or even derailleur cages and brake calipers), I frequently use Ajax and a green ScotchBrite pad to clean things up. You'll need to be careful if there are any decals/pantographs/anodizing you want to preserve.

ramzilla

I've got a tractor parked in the shed. So, always have a good supply of diesel fuel handy. My technique includes diesel, several clean 1 gal & 1 qt paint cans, kitty litter trays, elbow length nitrile gloves, wire brushes, shop rags. I completely disassemble bike. Roll up chain & place on bottom of 1 gal paint can. Put freewheel on top of chain. Toss in the FD & RD, both brakes, bottom bracket. You can fit everything in a one gallon can with the exception of the crank arms & chainrings. Pour enough diesel into can to cover everything. Put lid on hammer tight. Then, shake the the can vigorously. Let it soak overnight. Shake, soak, repeat, etc. Sometimes I soak stuff for several weeks while waiting for new tires & other parts to arrive. Eventually, I put on big nitrile gloves & fish everything out. Wire brush everything over a kitty litter tray. After I get the freewheel clean I'll soak it in automatic transmission fluid. Oh yeah. I've brought several very nice old Suntour freewheels back to life this way.