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-   -   Crank bolt cover/BB (https://www.bikeforums.net/showthread.php?t=1269394)

louky 03-26-23 09:14 AM

Crank bolt cover/BB
 
I want to disassemble this to service BB.

1) Does the crankbolt cover unscrew or pry out? I would like to not damage this if possible.
2) Is this tool what I need to remove the lockring on the BB? I know I can get it off with a punch or pipe wrench but would like to do it properly.
3) After the lockring comes off, is there a specific tool to remove the next part, or can I do it with a large adjustable wrench?
https://cimg0.ibsrv.net/gimg/bikefor...6664aa6195.jpg
Amazon.com : Park Tool (109917) HCW-5 Lock Spanner : Bike Hand Tools : Sports & Outdoors

Chuck M 03-26-23 09:22 AM

The cap should remove with a dime or large screwdriver. It may be stuck pretty well and some damage may occur. Can't say exactly but that appears to be an appropriate spanner for the lock ring. You will also need a crank arm puller.

FBinNY 03-26-23 09:23 AM

It's supposed to screw out. Use something wide, like a quarter. A narrower screwdriver blade will likely gouge the plastic.

Worst case, they can also be pried out without damaging the crank's threads.

louky 03-26-23 09:34 AM


Originally Posted by Chuck M (Post 22840882)
The cap should remove with a dime or large screwdriver. It may be stuck pretty well and some damage may occur. Can't say exactly but that appears to be an appropriate spanner for the lock ring. You will also need a crank arm puller.

Thanks. I do have a crank puller. I have taken this type of BB apart before, but always on bikes where it didn't matter if there were to marks left on the parts. Just trying to do it right (for a change :lol:)

Chuck M 03-26-23 09:45 AM


Originally Posted by louky (Post 22840897)
Just trying to do it right (for a change :lol:)

You will never know if it is done right in the age of Internet forums. People will debate argue if leaving the fixed cup on the other side alone or removing it too is the right way. I'm middle of the road on it. If it comes out great, but if it is going to take a lot of force and I'm not painting the frame, I leave well enough alone.

Kontact 03-26-23 09:47 AM


Originally Posted by louky (Post 22840897)
Thanks. I do have a crank puller. I have taken this type of BB apart before, but always on bikes where it didn't matter if there were to marks left on the parts. Just trying to do it right (for a change :lol:)

This is a very standard BB type. Please go to the Park website and read the tutorial, then buy the correct tools. The questions you're asking suggest you are about to damage something out of a lack of familiarity.

smd4 03-26-23 12:49 PM

Those dust covers are plentiful on eBay, should you damage it.

JohnDThompson 03-26-23 02:10 PM


Originally Posted by louky (Post 22840873)
1) Does the crankbolt cover unscrew or pry out? I would like to not damage this if possible.

It should unscrew. It helps to spray with penetrating oil prior to removal, especially if it has not been serviced in a long time. Some of those caps are plastic, and become quite brittle with age, and may shatter when you try to unscrew it. If that happens, drive out the shards (if any) with a hammer and punch, taking care not to damage the extractor threads.

2) Is this tool what I need to remove the lockring on the BB? I know I can get it off with a punch or pipe wrench but would like to do it properly.
Yes, looks good.

3) After the lockring comes off, is there a specific tool to remove the next part, or can I do it with a large adjustable wrench?
The Park HCW-11 is a tool designed for this task.
https://cimg8.ibsrv.net/gimg/bikefor...d0f07113e.jpeg
If you're lucky, the cup will not be too difficult to remove, in which case a 16mm cone wrench or even an adjustable wrench may work, if you're careful.

maddog34 03-26-23 11:18 PM

if it's a really old plastic cover, it will be brittle.. they crack 6 times out of ten tries.
when the outer portion of the cover breaks away, i've had to chisel the remaining threaded sections out many times.
the trick is to not damage the crank's threads.... and to work within the confine created by the nut or bolt holding the crank on the spindle...
Sometimes you can remove the nut or bolt first... it requires a thin walled, 14mm socket.

canalligators 03-27-23 09:21 AM


Originally Posted by maddog34 (Post 22841601)

Sometimes you can remove the nut or bolt first... it requires a thin walled, 14mm socket.

Actually, you must remove the bolt or nut.

maddog34 03-27-23 01:38 PM


Originally Posted by canalligators (Post 22841861)
Actually, you must remove the bolt or nut.

actually, no, you don't... but it sure helps.

and there are times when you CAN'T remove the nut since it's trapped by the cap's threaded section and there's no room to insert a socket.

i have about 75 bikes loaded in a trailer to be hauled to the scrap yard that say i know this subject well.

i use a specially ordered Snap-on Flat blade Screwdriver socket to remove the slotted caps.. the tip is @ 3/4' wide... i bought that tool to adjust mower reel bearings on an old Jacobsen Gang Mower.

what do you use?

grumpus 03-27-23 05:17 PM


Originally Posted by louky (Post 22840873)
I want to disassemble this to service BB.

1) Does the crankbolt cover unscrew or pry out? I would like to not damage this if possible.

This sort is supposed to unscrew; I use something like the edge of a cone spanner, but the caps are usually brittle and easy to damage. There are others that are push-in/pry-out which don't get stuck, but tend to fall out.

Originally Posted by louky (Post 22840873)
2) Is this tool what I need to remove the lockring on the BB? I know I can get it off with a punch or pipe wrench but would like to do it properly.

It's the right sort of tool, but I don't think there was ever a standard for bottom bracket lock-rings (beyond the de facto Campagnolo one) so the fit may not be great. The listing details some dimensions which might give you a better idea of how well it will fit.

Originally Posted by louky (Post 22840873)
3) After the lockring comes off, is there a specific tool to remove the next part, or can I do it with a large adjustable wrench?

There are spanners like this but again no standard to guarantee that it will fit. As long as it moves freely an adjustable wrench should be fine.

smd4 03-28-23 04:53 AM


Originally Posted by maddog34 (Post 22842144)
actually, no, you don't... but it sure helps.

and there are times when you CAN'T remove the nut since it's trapped by the cap's threaded section and there's no room to insert a socket.

You can service a bottom bracket without pulling the crank arms?

grumpus 03-28-23 10:13 AM


Originally Posted by smd4 (Post 22842648)
You can service a bottom bracket without pulling the crank arms?

He's talking about what happens when a crank cap breaks leaving its threaded part in the crank.


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