Ok, so I recently took the front and back wheels off, washed them and lubed them back up quickly, and went for a ride... however, by the time I got back, I noticed that there was a slight clicking noise with resistance coming from the back wheel. I thought it would just be the nuts contacting the frame so I sprayed some WD-40 on them thinking it would remove some dirt causing the problem. That was two days ago, and although yesterday was better, today I went out to the bike and now there's a loud, gritty noise coming from it when I walk the bike forward but not backwards. I'd rather hear from someone who may have had this problem before taking things apart, especially since it's only forwards and not backwards, so any help would really be appreciated.
What kind of bike do you have? Does it have a freewheel?
Good maintenance to your Bike, can make it like the wheels are, true and smooth!
Oh yeah, sorry, got ahead of myself: it's a Motobecane Mirage Sport, maybe 20 years old, although it's in very good condition and I replaced the tires, derailer, chain, etc... and forgive my ignorance but a freewheel means that while the bike is moving forward, the pedals don't necessarily move with it, right? That's the case with my bike. Lubricating the inside of it helps but I'm nervous about taking it apart so I figured I'd ask- the problem arose after I sprayed dirt out of it.
To me it sounds like you cleaned out the lubricant from the ratchet mechanism when cleaning the bike. This would be bad news as in order to really get it right you'd have to overhaul it. If it is a freewheel (as opposed to freehub + cassette) you can get one for dunno, 16 EUR (18 USD?). Freehubs are more tricky.
Lay the bike on it's side and drip some motor oil into the rear gear cluster right at the gap between the part that turns when you pedal backwards and the part that stays still. Keep pedals backwards a little to help the oil work in. If the sounds gets quieter, you know that is the source of the sound and you'll probably be able to get some more use out of it.
It sounds like you got water, soap, and/or WD40 into the bearings in the gear cluster and quite likely into the wheel bearings as well. You might want to think about opening up the wheel bearing and regreasing them as these are more expensive to replace than the freewheel. You really need to be careful when washing a bike not to spray stuff into where the bearings are. Usually best to spray cleaner onto a rag and then wipe the bike by hand.
Ok, so I took the axl part out of the freewheel and oiled the ball bearings inside, put the axl back in, and put the wheel back on (sorry for the lack of correct terminology here). I didn't take the actual freewheel of of the wheel itself. The noise generally went away for a little bit.
Several hours later, the noise is back! What happened, I'm using general all-purpose oil (3-in-1 brand), should I be using something else?
Please use grease to lube ball bearings, oil will flow out.
Yes, if you can actually get at the bearings, use grease. Automotive bearing grease is fine if you want something cheap and easy to get. I am assuming you took the axle out of the hub and lubed the wheel/hub bearings. The freewheel screws onto the body of the hub, but has it's own separate set of bearings. I recommended putting oil into the freewheel as it is a quick way to get some lubricant inside the freewheel which is a bit trickier to take apart than the hub/axle. You can also get away with oil in something like a freewheel which doesn't really have a lot of load on the bearings. But bearing like the wheel, bottom bracket, etc. that have high stress on them need something sturdier like grease or the lube will not last more than a couple hours as you've discovered. I'd also recommend taking the time to clean the bearing thoroughly before lubing. Putting new grease on top of old grit kind of defeats the purpose of the whole exercise. But kudos for getting in there and working on it. Best way to learn...