Author Topic: Cb750 K0 -oil gallery plug under shifter cover? (Read 14651 times)

scottly · « **Reply #25 on:** December 17, 2011, 03:46:51 PM »

My K1 has no plug, nor does my K7 parts motor. The shift cover gasket seals the hole. There is a "lump" on the inside of the cover over the hole.

MRieck · « **Reply #26 on:** December 17, 2011, 08:23:57 PM »

Quote from: scottly on December 17, 2011, 03:46:51 PM

My K1 has no plug, nor does my K7 parts motor. The shift cover gasket seals the hole. There is a "lump" on the inside of the cover over the hole.

The K7 should have it.....I'm sure of that.

ekpent · « **Reply #27 on:** December 17, 2011, 08:31:08 PM »

Maybe my gasket theory from some pics holds oil

scottly · « **Reply #28 on:** December 17, 2011, 09:06:18 PM »

Has anyone actually seen one of these plugs?

ekpent · « **Reply #29 on:** December 17, 2011, 09:09:39 PM »

Quote from: scottly on December 17, 2011, 09:06:18 PM

Has anyone actually seen one of these plugs?

Pictures or it did not happen ----

Magpie · « **Reply #30 on:** December 17, 2011, 09:58:49 PM »

Pics>

CB750F2 · « **Reply #31 on:** December 18, 2011, 02:37:39 AM »

Has anyone actually seen one of these plugs

Yes. I have two motors. One is a K1 and the other an F2 and both motors have the plug fitted. As I said in my earlier reply the Part No. is 11209-300-000. Doesn't the "300" part of the part number indicate that it the early models were fitted with the plug? Pat

markb · « **Reply #32 on:** December 18, 2011, 05:02:32 AM »

Quote from: MRieck on December 17, 2011, 09:49:18 AM

Quote from: markb on December 17, 2011, 08:54:15 AM
I wonder what the odds are that I happen to lose at least 3 plugs without realiziing it.
Very, very slim. It appears they did not come on the first bikes. I retract my earlier statement. That being said I would still plug it if possible.

When I read my statement back it sounded like I was trying to be a smartass. If anyone took it that way I apologize. I'm just amazed I never saw this plug before. They obviously exist.

Quote from: CB750F2 on December 18, 2011, 02:37:39 AM

Doesn't the "300" part of the part number indicate that it the early models were fitted with the plug? Pat

Yes, that would indicate that they were first used on the K0's.

K5owner · « **Reply #33 on:** December 18, 2011, 06:10:52 AM »

I have a new case & will take a look at it, take some pics. If the case doesn't have the plug; I'll measure and see what it would take to machine one out of aluminum. Hope to post something later today.

-Ray

markb · « **Reply #34 on:** December 18, 2011, 09:01:21 AM »

OK Cliff, I looked again at my cases. None of the three early ones has a hole with a flat. E100 appears to have the remnants of an M6 thread. The others don't appear to have been threaded unless they were drilled out with a larger drill.

I'm speculating that the original intention might have been to use a threaded plug and abandoned along the way. The other end of the hole is permanently plugged with something that looks like JB Weld. I guess they all have that.
Unless you want to, I'd be tempted to post this on the SOOC site to get a read on this from the sandy experts.

Magpie · « **Reply #35 on:** December 18, 2011, 10:39:16 AM »

That's really interesting Mark. I searched through my cd's of saved pictures and found one of engine 260 with a round hole but can't see if it's threaded. You would have a better response from the sandcast guys since, like me, they're drooling over your latest project.

markb · « **Reply #36 on:** December 18, 2011, 01:32:28 PM »

Cliff, I posted it over at the SOOC site. It will be interesting to see what they have to say. Here's a link to the thread:
http://cb750sandcastonly.com/smf_forum/index.php?topic=695.msg4560

Magpie · « **Reply #37 on:** December 18, 2011, 02:08:05 PM »

Thanks Mark! That's a nice clean engine case! So, I bit the bullet, got an Athena cover gasket, and as per Hondaman's suggestion in his book, smeared a very thin coat of Permatex Grey on it, made doubly sure the screws were the right length and put it together. I have just put my flame suit on however it's not leaking but I'm eagerly waiting for a response to your post on the sandcast forum.
Now on to more leaks. There's a weep of oil at the end of the front corner of the motor where the cylinders meet the head. I'm hoping that merely retorquing the head will fix this. I don't know if the head was planed previously but a machine shop said the head and cylinders were flat. A local Honda mechaic said to use 2 washers on the ends of the studs to be sure I'm tightening to the stud and not the end of the stud threads. he bumps the torque to about 20 pounds on the head studs. Any thoughts on this one Mark?

K5owner · « **Reply #38 on:** December 18, 2011, 02:38:24 PM »

Here's a pic & specs on the oil galley plug.

Quick sketch, not to scale
-looks like I'll be making one of these because it doesn't come with the new case

Magpie · « **Reply #39 on:** December 19, 2011, 11:05:09 AM »

From the sandcast forum
"Sandcast bikes rely on the gasket to seal off the end of that oil gallery. "Later" bikes use a rubber plug which has a lip that sits in a small shallow counterbore at the end of the gallery to seal off the gallery. I have never come accross any reference to this plug in the parts lists, and have no idea when it was first fitted." Cliff.

andy750 · « **Reply #40 on:** January 02, 2012, 10:21:38 AM »

Just to add to the information on this thread and because I removed the gear shifter cover on my K2 today - CB750K2 with plug:

Andy

Dunk · « **Reply #41 on:** July 05, 2014, 04:46:36 PM »

Any source for these plugs or off the shelf plug that will work? My K1 is leaking at the bottom the the shift cover gasket and this is the only thing I can figure it to be. Just changed the gasket again and it seems to be leaking less, but it leaking right in this area. Just noticed the oil gallery in mine with no plug and thinking that's where it's coming from.

Dunk · « **Reply #42 on:** August 08, 2014, 06:02:22 PM »

Had anyone made a part for this? Thinking of trying cutting a small piece of rubber out by hand to tap in the end of this passage May a piece of aluminum dowel that I can turn down to a slight press fit and use bearing and sleeve sealer? My concern is that it doesn't end up too deep and starve the transmission for oil. Just living with the leak for now but it is definitely annoying. Not profuse but it leaves a spot wherever it sits.

scottly · « **Reply #43 on:** August 08, 2014, 10:22:33 PM »

Quote from: cadunkle on July 05, 2014, 04:46:36 PM

Any source for these plugs or off the shelf plug that will work? My K1 is leaking at the bottom the the shift cover gasket and this is the only thing I can figure it to be.

My K1 doesn't have the plug and doesn't leak. It's more likely oil coming from the automatic chain oiler, or a leaking shifter seal.

Dunk · « **Reply #44 on:** August 09, 2014, 05:07:48 PM »

No and no. Drive sprocket area is dry. Neutral switch is new as I suspected it was that before restoring the bike. It's now definitely not leaking from the neutral switch or oring. With bike running I can wipe it dry , wait a bit, then it'll only be wet at the shift cover gasket in the area of this oil passage. Driving me nuts.

scottly · « **Reply #45 on:** August 09, 2014, 06:42:52 PM »

If you are sure it is leaking from the shifter cover gasket, and not migrating there from somewhere else, pull off the cover, remove the gasket, and see how flat the cover sits against the case. Make sure the locating dowel near that area is not mangled, preventing a good seal. Also, inspect the gasket to see if there is a slight imprint of the galley hole.

Elan · « **Reply #46 on:** November 01, 2017, 11:48:28 AM »

Shamelessly bringing this post back from the dead. I have this plug in production and it will be available soon

Jerry Rxman Griffin aka MuthaF'er · « **Reply #47 on:** November 01, 2017, 01:17:28 PM »

No shame to that!! Thank you AGAIN. What's next??

PeWe · « **Reply #48 on:** November 01, 2017, 02:08:17 PM »

Easy to loose the rubber plug when cleaning the case. I have done it twice with pressure washer. when flushing the oil channels inside. PLOP! and it flew a meter. I was lucky both times and saw when it happened. K6 and a K2 case.
Is it nitril rubber? I guess that all rubber and O-rings in the old CB's were nitril rubber? Viton is a later rubber?

Dunk · « **Reply #49 on:** November 02, 2017, 08:05:59 AM »

Elan, thanks for producing this particular piece of unobtainium. I was able to find a plug still in a spare engine to use of mine, but new plugs will be much easier than the various alternative methods of plugging this hole. I'm in for a couple of them when these are available.

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Author Topic: Cb750 K0 -oil gallery plug under shifter cover? (Read 14651 times)