Classic & Vintage - Regreasing cottered crank bottom bracket without removal

This is probably high up there in lazy maneuvers so I'm expecting a lot of no's, but has anyone ever greased a bottom bracket on a bike with a cottered crank without removing the crank arms?

I don't even know if this is physically possible, depending on clearance between the crank arm and the bottom bracket shell. I'm just asking because I got a free high-ten azuki off craigslist and both bottom bracket cups have notches that fit the 3 slot end of my park lockring tool. They're loose enough that I'm able to easily adjust both while the crank arms are still on. The bottom bracket could probably use some grease but I really don't want to futz with the cotters if at all possible.

This is probably just karma for scoffing at the price of the $50 cotter press tool a week or two ago, but that tool still costs $50 more than what I paid for this bike and I don't plan on adding any more cottered crank bikes to the stable.

Or... does anyone in San Diego have one of the cotter presses I could borrow? :)

There are other ways of getting a cotter pin out, you know. Not with a hammer, of course. I have a small vise that I got at a yard sale for a couple bucks; I think it came on a drill press or something once. That, together with a socket, always works for me. Sometimes I tighten the screw up until it won't go anymore, and the thing still won't budge; then one good tap with the hammer is all it takes.

If you really don't want to do any of that... oh, fine. Why not just get some fairly runny grease and dump a lot of it down the seat post? Of course you won't know whether it actually gets all the way down there unless you pack the whole seat tube with grease... In fact, I think I read about that in the "bonehead moves" thread!

I'm a caveman. I just use a hammer and a piece of pipe on the opposite side of the cotter to help relieve the force of the hammer strike.

I haven't done it but if you can get the grease in there go for it. I'd say the possibility depends on how deep the BB cups are and you won't know that until you give it a go. You could spray some brake cleaner, etc in there to clean things up first but that stuff is pretty toxic so be careful. You could also try shooting grease into the gap between the spindle and cups with a giant syringe.

Oil into seat tube if it is an older Raleigh Sports that took oil anyway.

has anyone ever greased a bottom bracket on a bike with a cottered crank without removing the crank arms?

Yes...well tried is more like it.

Discovered the meaning of 'LOOSE' ball bearings. ;)

Doh!

Oil into seat tube if it is an older Raleigh Sports that took oil anyway.

+1. however, if there's a bunch of scaly, rusty, flaky stuff down in the BB shell, it's going to mix with the oil. but i have heard from others that this is a viable way of getting some lube down there. some people claim oil is better for bearings than grease, anyway.

Hammer is bad.

I used a C Clamp and a 15 or 16mm socket.

Undo the nut/cover on the cotter

Place the socket over the other end of the cotter.

Place the "spinny" portion of the C-Clamp on the socket

Placed the "fixed" side of the C-Clamp on the nut side.

Tighten the clamp until the cotter pops out into the socket cup.


If you place the "fixed" end of the clamp on the socket, it tends to fall off and the socket slips out.

I also let some Tri Flow soak in overnight.

Don't use a hammer. I wrecked the pants leg protector thingy on my chainrings when I missed.

Regardless of how you do it, you'll need to completely remove the old contaminated grease, have clean dry cups for the new lube, and replace the balls. If you don't, I really think you would do better to leave things undisturbed, rather than get to stirring that witches brew of scale and rust and silica.

Regardless of how you do it, you'll need to completely remove the old contaminated grease, have clean dry cups for the new lube, and replace the balls. If you don't, I really think you would do better to leave things undisturbed, rather than get to stirring that witches brew of scale and rust and silica.
+1 Once you get used to it, pulling a cottered crank is not a big deal.

Don't use a hammer. I wrecked the pants leg protector thingy on my chainrings when I missed.

Very true that is a real concern. I'd prefer the special tool thing if I had it.

dude you dont want to clean and relube the BB that is clear - the bike was free this is also clear - so just ride the darn thing and enjoy it

RHM, I can't wait to try your socket and c-clamp technique! I have a Hercules to test that on. It sounds promising.

To the OP, I bet you could find a local bike shop to remove those cotter pins for a very small fee. Remember to buy new ones and not re-use the old.

About greasing with partial disassembling - See these pictures:

http://dl.dropbox.com/u/4370787/Gre_0704.JPG

http://dl.dropbox.com/u/4370787/Gre_0705.JPG

http://dl.dropbox.com/u/4370787/Gre_0706.JPG

You should know, just in case you don't, that Alemite makes an attachment for their grease guns that has a very small orifice for grease application in tight spots. Here is a picture I just took of mine in action. Squeezing the handle quickly shoots a thin high-pressure stream of grease about four feet (in the USA) or 1.3 metres (in Canada). I have found this invaluable for putting grease quickly into tight places that have been flushed out with thin oil or kerosene & blown clear with compressed air.

You should also be aware that Keystone (and others) makes an adhesive lubricant known in the industry as "open gear grease" that comes in aerosol cans and can be squirted as a foam (!) into very close quarters. They all have good adhesion and the lithium-based types are water resistant. Better than oil in places where grease is required but difficult to get it into.

I have a good collection of specialty tools and dry and wet lubricants designed for use in machining and maintenance procedures. The grease fitting that squirts grease is especially useful because it allows precise placement of the lubricant.

RHM, I can't wait to try your socket and c-clamp technique! I have a Hercules to test that on. It sounds promising.

To the OP, I bet you could find a local bike shop to remove those cotter pins for a very small fee. Remember to buy new ones and not re-use the old.

No, that was The Golden Boy, who suggested a C-clamp. C-clamp technique is trickier; I use a small vise! The thing about the C-clamp is that you want the jaws open about 2" and a 2" C-clamp is way too flimsy. 6" C clamp may be beefy enough to do the job, but then you have 4" of thread sticking out the adjustable end, and this makes the whole thing a little floppy; as a result the force can get a bit oblique, which will bend the cotter. If you use a C-clamp, better make yourself a large spacer, like a thick chunk of oak with a hole in it, instead of a socket. You can do it, but a vise is foolproof.

Here's my home made cotter pin puller/press and it works just grrrreat!


Anyone with a welding machine and access to these simple components, can make up one of these little tools.

Slip the too onto the appropriate end of the cotter pin, snug up the bolt and give a little tap on the end to set the taper. Tighten and tap again. Just tap, you do not have to hit hard.

Things might not free up immediately and a wee bit of WD40 might prove useful.

Anyway, hope this is a help.

177516 177517

^I was hoping randyjawa would show us that thing again. I want one. Brilliant!

Hmmm.. lazy way to clean/grease the BB beraings and races??
I would think that you could just pour copious amounts of mineral spirits through the seat tube and down into the BB shell (remember to spin the BB axle when you are pouring in the mineral spirits and have a bucket to catch the mess). You should be able to flush out a good amount of any old grease and dirt that have accumulated in the BB shell and bearings draining out through the BB drain hole(s) and the seams between the BB axle and cups doing so. Make sure you have the seat stays tipped up so the gunk does not end up in them. After you think you've got most of the dirt and gunk out, you can seal the seam between the BB axle and the cup opening with maybe modeling clay and leave a small gap to jam the tip of a grease tube against or into it. Push enough grease into the seam and it should easily work it's way towards the bearings and races when you spin the axle while pushing in the grease. Repeat on the other side and you are done.
Of course I only recommend doing this if for some reason there is just no parctical way you could open up/dismantle your BB to properly service it....or if you are just really really lazy cyclist......:rolleyes::D

Chombi

No, that was The Golden Boy, who suggested a C-clamp. C-clamp technique is trickier; I use a small vise! The thing about the C-clamp is that you want the jaws open about 2" and a 2" C-clamp is way too flimsy. 6" C clamp may be beefy enough to do the job, but then you have 4" of thread sticking out the adjustable end, and this makes the whole thing a little floppy; as a result the force can get a bit oblique, which will bend the cotter. If you use a C-clamp, better make yourself a large spacer, like a thick chunk of oak with a hole in it, instead of a socket. You can do it, but a vise is foolproof.

Ahh, I understand. The only C-clamp I have is huge so that may present a problem. My vise is broken, I've been looking for a reason to buy another.