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Resurrecting a 79 CB750F SS

Well today I pulled the plugs, valve cover/right side engine cover and changed the oil. I poured some motor oil on the cams, they were bone dry.
I think this looks ok
IMG_20171111_122017128[1].jpg
The number two spark plug gave me some grief. At first I thought it was cross threaded but it just had a bit of corrosion on it.
IMG_20171111_114901353[1].jpg
Are these cracks? I can't see anything on the outside of the cover.
IMG_20171111_124908351[1].jpg
Is this normal?
IMG_20171111_124148407[1].jpg

I have an endoscope on order, it should be here tomorrow. Now I'm going to check the valves. At only 8000 miles I hope they're still in spec.

Al
 
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I just did the valves. It looks like they're dead-on.

EX1 .003 .005 EX3 .005 .006 in
IN 1 .004 .003 IN3 .004 .004 in

EX 2 .004 .004 4 .006 .005 in
IN2 .004 .004 4 .005 .005 in

I'm pretty pleased with these findings. I'm going to order a new gasket and screw and put it back together.
 
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Well today I pulled the plugs, valve cover/right side engine cover and changed the oil. I poured some motor oil on the cams, they were bone dry.
I think this looks ok
View attachment 8094
The number two spark plug gave me some grief. At first I thought it was cross threaded but it just had a bit of corrosion on it.
View attachment 8095
Are these cracks? I can't see anything on the outside of the cover.

View attachment 8096
Is this normal?
View attachment 8097

I have an endoscope on order, it should be here tomorrow. Now I'm going to check the valves. At only 8000 miles I hope they're still in spec.

Al
Not cracks, my cover has those too, they look like possible faults in the casting die. Clean off the rotor ring contacts with electrical contact cleaner. Check the brushes in the cover for useable length and free moving.
 
Well the new master cylinder arrived today. I was getting ready to fill and bleed when I saw this.
What is that thing down inside near the ports? I found a google image of it in a CX650 but in that picture it's rotated 90 so the round metal tip is closer to the return port.

clip.jpg

Confused,
Al
 
Last pic is too small to tell anything (master c).

Can't tell from #2 plug pic very well either but it looks like it has some aluminum in the threads meaning you lost some thread from head and now easier to strip it out. What forcing parts over corrosion does with no lube.

Those aren't cracks, Chris has it right.
 
That thing in the MC has a part number. A guy from ADV confirmed that it belongs there. Now I have brakes.
I sprayed PB Blaster on the spark plugs about a week before I pulled them. Glad I did, not telling what would have happened. I'm going to use the endoscope to take a better look at the threads on cylinder two.
 
Luck................the part you speak of could be a fluid deflector of some type to prevent the compensation return shot hitting the cover gasket, that lends toward leaking.

I myself would correct any shims at .003" since .002" is effectively zero and WILL burn like that. Why we use .005" as a set-to number instead of the service manual .003", the latter causes a lot of valves to burn for no reason.
 
Well I decided to check out the cam chain tensioner today. The lock nut on the front adjuster busted loose with little effort, however, the bolt is stuck. I put a ratchet on it and tried to loosen it a bit, no go. Then I tried to tighten it a bit, no way. Not sure what's going on with it. I'll take a better look later. Got it!
Now I'm waiting on the valve tool, I'm going to swap a few shims from EX 1&3 and then pull one out of IN 3 and see what size I need. I found cool formula on how to calculate shim thickness: https://www.youtube.com/watch?v=tl9Cze6WcKI I think this method is a lot easier than trying to use that chart in the manual.
 
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Luck................the part you speak of could be a fluid deflector of some type to prevent the compensation return shot hitting the cover gasket, that lends toward leaking.

I myself would correct any shims at .003" since .002" is effectively zero and WILL burn like that. Why we use .005" as a set-to number instead of the service manual .003", the latter causes a lot of valves to burn for no reason.

EX1 .003 .005 EX3 .005 .006 in
IN 1 .004 .003 IN3 .004 .004 in

Well I managed to swap the .003 and the .006. Now they read .004 and .005. I ordered a shim for IN 1 V2 that is .05mm thinner. Hopefully that'll do the trick
 
Spiffy. Always look at the wear pattern on used shims, most polish only and fine but occasionally you get a specific wear pattern and best not to swap that one to another lobe as it can bring on sudden wear.
 
Spiffy. Always look at the wear pattern on used shims, most polish only and fine but occasionally you get a specific wear pattern and best not to swap that one to another lobe as it can bring on sudden wear.

I didn't notice a wear pattern on either of them. With only 8k on the odo I wasn't really expecting to see any. When I rebuilt the engine in my Saab I had to keep track of the hydraulic valve buckets. Styrofoam egg cartons came in handy!
 
I think it's going to look OK. When I put new tires on it I plan to remove the swing arm and blast/paint it. Or I might just get a used on from Ebay. It's probably cheaper that way anyhow.

IMG_20171119_105655772[1].jpg
 
Well she cranked but did not fire up. After I pulled off the carbs I noticed fuel going into the cylinders

IMG_20171120_172544253[1].jpg

Then I proceeded to remove the bowls. I didn't remove carb 2 bowl yet. I want to read more about that. But feast your eyes on these. Now, I'm a novice a carbs but I noticed right away that something was amiss. Yes, that's what I found when I removed the bowls.

IMG_20171120_174544845_HDR.jpg
IMG_20171120_174645865.jpg
IMG_20171120_174811192.jpg



I also noticed that the rear right valve cover bolt hole is stripped. What would be the best way to fixing that?

I got a pretty good picture of each jet. I thought primary was 68 and secondary is supposed to be 98? Isn't 120 a HUGE jump?
2017-11-20-20-04-08[1].jpg
2017-11-20-20-08-15[1].jpg
 
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