Topic: 1978 CB750K — Post 836 OIL PRESSURE - not good

[the technological J]

i ws reading and not sure if it wsas addressed but if u bead blast the engine you'll want to paint it as soon as possible... aliminum oxidizes fast .... it wont hurt the fins or anything but it''l look like crap real quick

[SKTP]

If I polish the aluminum, then I don't have to paint, correct? Or are people clearcoating after polishing. Sorry I'm sure this has been addressed before, I'll get searching.

Thanks for the comments. Hopefully I'll get a look at the pistons later today or tomorrow. Are broken rings uncommon? I hope the inside of the cylendars are not all scored up...I'm guessing there'd be quite a compression loss with that much ring gone? This is the best Lego set ever!

[fastbroshi]

  Right.  I don't think clearcoat would stick at all if you polished.  Haven't seen any polished blocks besides one on Carpy's site.  Lot of maintenance to keep it looking tip  top.  I wouldn't call broken rings common but it happens.  And yes you're going to lose compression with broken rings.  The pressure in the cylinder basically leaks right past it. 

[the technological J]

i have some polished aluminum and mothers cleans it up real well i wouldnt worry about clear coating it ... but i would keep up on it every couple of months with some mothers other wise you'll completly lose the polish to it and have to redo it

[SKTP]

Got some more work on tear-down done yesterday...all the cylinder rings appear to be intact. I'm going back to thinking that broken bit is a shifter fork...I should know soon as the case-split should be happening soon. My girlfriend helped with this session. My impact driver just arrived today from Sears, clutch and Alternator out soon...

[SKTP]

Just noticed that my right and left are reversed in that jPeg. In reality, the right is the right and the left is the left. I just messed up the lables in Photoshop.

[SKTP]

Any tips or step-by-steps on removing cylinder studs?

[fastbroshi]

  On mine I used an old fork leg to bend over a stud, then heated the part of the block it was screwed into for 20 seconds or so, then tried to turn it out with that same fork leg I was using to bend them over.  I snapped one but that was the night before, I started by using a small pencil torch and it ran out of fuel.  I tried to turn it anyway.  Doh!!  
  On that note, I didn't like the way my threads looked and want to chase all the crap out of them.  Does anyone know if you can use a standard type tap to chase these?  I thought I read somewhere you shouldn't as it enlarges the threads slightly.

[SKTP]

You have to bend them?!!! Do you plan on bending them back and using them again? There must be another way?

[MCRider]

I recommend using a stud remover. (Duh). Like this: http://www.harborfreight.com/1-2-half-inch-drive-stud-extractor-94640.html

Allows you to get low on the stud, reduces likelihood of breaking. Get a big breaker bar on it. 3/8" allways worked for me but it will take 1/2".

Heat and penetrant is good also.

[fastbroshi]

  Sorry, I assumed you wanted to remove them to replace with the heavy duty variety.  I didn't try any other way since I'm replacing mine.  You could try the double nut technique, after hitting the block with some heat of course.

[fastbroshi]

That particular tool sucks if you snap off any of your studs too close to the face of the case.  Any tips on removing one of those MC?   We're talking MAYBE a .5" to work with.

[MCRider]

That particular tool sucks if you snap off any of your studs too close to the face of the case.  Any tips on removing one of those MC?   We're talking MAYBE a .5" to work with.

I  have an example of that in my build thread, but I'd play heck trying to find it. I bot a set of cases off ebay with the studs out except one broken off with probably a 1/4 in above the surface. Took it to a machine shop. They welded a rod about 4" onto the stub. Heated the cases and turned it out. Cost $25.  Others have had some luck drilling it out but it takes precision, like a really good set up vice and drill press or mill to be accurate enough.

[SKTP]

Is it possible to split the cases with them (the studs) still in place? I imagine it'd be akward but maybe possilbe? What do the studs mount into? Only the top case, or all the way through? No books or manuals seem to have much info on the studs. One step they are there, then magically they are gone? Thanks for nothing books! :p

I guess $80 for APE studs isn't so bad especially since I hope I will never ever have to re-split this engine.

[MCRider]

Is it possible to split the cases with them (the studs) still in place? I imagine it'd be akward but maybe possilbe? What do the studs mount into? Only the top case, or all the way through? No books or manuals seem to have much info on the studs. One step they are there, then magically they are gone? Thanks for nothing books! :p

I guess $80 for APE studs isn't so bad especially since I hope I will never ever have to re-split this engine.

The studs are in the top case only. In the world of stock engines the studs are never removed. It is not necessary to remove them for any purpose other than to replace them.

I'd upgrade to the HD studs if at all possible but hey that's just me. Many say no, and I can respect that. I think they contribute to a more oil tight engine.

If you break an old one getting it out you will likely have to split the cases to get the stub removed. I've taken out 2 sets personally and didn't have one break. I've seen and heard of many breaking, usually just one per engine that is. Soak and heat and go easy with a good tool.

[SKTP]

Thanks...

[SKTP]

Took a little break from engine tear down and mocked up my CB450 K0 Black Bomber headlight nassal...I'm super hyped on it.

I took apart an old Tach to see why the Black Bomber tach might be seized...it looks pretty simple in there...I'm going to try to make the paint-can opener tool tonight as the most difficult part of tach-rebuilding seems to be cleanly opening the rim

Anybody know how the Bomber Tach is suppose to mount in the bucket? I do not have the rubber part...I was thinking inner-tube pieces?





- Is part 27 a chunk of rubber? I have the speedo/tach unit, the bucket and part 26.



- Are 6" head lamps (the bulb part) fairly universal? I think David Silver Spares has a re-pro of the rim...and yes, I will be getting rid of the MASSIVE turn signals

[fastbroshi]

  Sorry no info on the Black Bomber tach, but I'm a big fan.  Not gonna follow you on Twatter though, sorry.  Isn't it cool how the odometer goes vertically? 

[SKTP]

Not gonna follow you on Twatter though, sorry. 

I don't have Twitter or Twatter?...I love how the odometer goes vertically. I wonder if the readings will be remotely close to accurate...I know I saw a calibration thread somewhere...

[Jerry Rxman Griffin aka MuthaF'er]

Is that broken ring-looking piece the retainer for the final shaft? You'll know when you split the cases.

That mystery bolt doesn't appear in the manuals as it's on the later engines and not the earlier.

I'm with MC on the studs and the tool. Double nutting might work but you will twist the whole shaft and have a bigger potential for breaking one. Grip them down low with the tool. Just don't get on the base and gouge it. I've done 2 sets also and haven't broken one yet. I took out a set this past week. Sprayed with PB Blaster the day before. Didn't need to apply heat. I found 3 loose studs with 1 that had the top of flange above the base. All the head bolts were relatively loose too. No wonder it leaked oil. I'm damn glad I got Gordon's Frame Kit installed. I'll be able to retorque the head this time. I'm using the APE HD studs too.

[SKTP]

Almost there. Sure have learned a lot about how everything goes together (I hope?!). Here's the latest batch of teardown. I must be the slowest ever.
I have learned a couple  of things that are not immediately obvious to a newbie:

- you do not have to disconnect the alternator wiring to get it off

- after consulting this thread: http://forums.sohc4.net/index.php?topic=59158.0
I probably should have left the top alone and taken the bottom off and got the tranny working before taking everything apart
It appears you can spilt the cases with the top end on (maybe everybody knows this already). Due to the massive amount of cleaning/polishing/painting I am going to do. I think I am OK with it (top end disassembly) plus the top end was pretty easy to take apart and seems less complicated than originally thought (again, I'll prove it to myself when the bike runs again.)

- don't think I needed to take the clutch apart. (questions about clutch below with the photos)

Here's the pics...I hope to split the cases tonight after work

rolling chassis. taking that apart is phase #2


Alternator wiring...so dirty I'm not even sure of the wire colors.


Piston are pretty easy to remove

here's 4 angles of one piston. I am starting to think that I have gone this far, why not go 836cc?



clutch disassembly


what tool grabs that circle bolt with the 4-notches? Any link to tool appreciated. I want to tourque it back on properly. I smacked it off with a hammer and screwdriver to get it started then used think nosed vise grips that I ground down to fit in the notches. Why would they use such a weird nut?


Right around when I took off that c-clip I thought, I really doubt I need to take this clutch basket off. I think that clip is going right back on. How would you get it off if you had to. Is there a way to get around the manual's suggested "sproket puller"?


The shifter linkage seems pretty straight forward










starter removal



Thanks for any tips or feed back...soon the cleaning begins

[MCRider]

Alternator wiring: In the gang of 3 that has one yellow wire...they are all yellow and it doesn't matter which goes where.

[SKTP]

Arrrrgggghhhhh!!!! So the cases are split the tranny is out of the bottom case and I can see those half-moon bearing retainers on the top cases tranny area. But nothing looks like the other chunk of the mystery broken bit?! What the heck is it?! I'll be taking more apart all week. There's almost no more to tear-down. I hope I can figure out what was messing up the tranny....case-splitting photos to be posted soon

[jaguar]

is that normal for the master?
or was it a bad coating?

i was going to have my calipers done and thought about doing the master too.

[SKTP]

I'm pretty sure that's what brake did to the powder coat