In Search of the Elusive Spooge, Rear MC, 76GL1000

[leonardhcross]

After a failed attempt to relieve binding of my rear brake calipers on my 76 project bike, I reviewed NGWClub forums once again. Most of the submissions indicate that a plugged spooge hole is the most likely source of my brake binding. However, the forums have given some conflicting thoughts on how to locate the spooge hole with some saying that it is under the reservoir and others saying that it can be found by removing the threaded plug on the back of the cylinder. In this video, I am including both a graphic image and a photo which show conclusively how to locate the elusive spooge hole. In the photo, the red arrow is pointing at the spooge hole which, as you can see, is at the back of a depression or dimple. The photo found in a post by member NotSoLilCrippseys is definitive. Now, all I have to do is to find a way to unplug it..https://www.youtube.com/watch?v=IRFaLlR ... u3&index=1

[robin1731]

Are you refering to the return hole?

[leonardhcross]

Are you refering to the return hole?

Yes. It is commonly referred to as the "spooge" hole. I do not know the origins of that name.

[pidjones]

I use a high "E" electric guitar string for that and the pilot jets. I have a section chucked up in a pin vice.

[leonardhcross]

I tried probing the dimple with a piece of high E guitar string but it was not stiff enough to start an opening. I have now ordered a pin vice. Looking forward to unplugging that tiny return “spooge” hole.

[CYBORG]

"spooge" hole. Now there's one Bob can have some fun with.

[Sagebrush]

Cut a bristle from a wire brush or wheel and hold it with a needle nose to unplug it.

[Rat]

"spooge" hole. Now there's one Bob can have some fun with.

But … but … that's the proper name for that tiny little return hole … isn’t it ???

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Google shows this for spooge hole …



Gord(must be true)Jones

[redglbx]

[Whiskerfish]

Looks like the correct nomenclature is "bypass hole" or "bypass port". The larger hole should be the "intake/return hole" depending on the application. The reason the bypass port is so small is that at the very beginning of the piston stroke it is open to the pressure being sent to the caliper. Once the piston moves past that point the port is blocked and the brakes get 100 percent of the pressure developed by the piston. It has to work that way for thermal expansion and to allow you to bleed the system. We got smart about the bleed part working on Liam's 1200 . The spring in the rebuild kit we had (brand new) was a few mm too short and did not push the piston back past that port, so our repeated efforts to bleed the system were frustrating to say the least. These pics are generic, not GL specific and borrowed from http://www.mgb-stuff.org.uk/bmaster.htm

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[Rat]

One of the few times my ‘supervision' actually helped …

Gord

[CYBORG]

Thankyou Bob

[leonardhcross]

These responses are fantastic! All I can hope is that some newbie down the road with a seized rear caliper can type in "rear brakes seized" and get directly to this link. The forum at it's best.

[Whiskerfish]

One of the few times my ‘supervision' actually helped …

Gord

Who said supervisors don't count

[Whiskerfish]

Thankyou Bob