Topic: Fresh meat, engine teardown questions

[Muddyape]

Bought a 1976 CB550k with 10,000 miles on her a couple of weeks ago for $500. I tore it down and dug into the motor which fired right up when I went to look at it three weeks ago. So couple of questions;
1) while I have it apart should i replace the rocker box with a later version to avoid potential problems with the outer cam journals going out of round that I've read about here. Right now everything seems in order.
2) heavy carbon build up on piston tops, valves and exhaust ports. Should I just clean, hone and replace rings? Bores seem to be in good shape with no obvious scoring. 
3) having horrible time removing cylinder block from case. Dont want to start bashing the fins off to get it loose. Suggestions?

Just looking to freshen her up like new. Replacing gaskets, o-rings etc. Any other advice?

Thanks, Brian 

[Duke McDukiedook]

Uhm, if everything fired up and ran just fine when you first bought it why would you tear the engine apart?!?!?

Got a tasty batch of meth last week?

[Muddyape]

Nah, no meth. Planning to build this nice and want to know everything about it (inside and out) have another bike (an HD) and will take my time with this, powdercoat engine etc. Got a bit of the OCD and just like things the way I like. So teardown seemed logical.

[faux fiddy]

Geez= 10,000 miles and a runner, no wonder it doesn't want to come apart.

I figure the best way to make a call on the bores is to use a inside guage and see, but they are prolly fine.

If you wanted a built, balanced, bored out motor there are plenty of old cores available around here  with problems to start out with that would make a good project.  This one you might just want to clean some carbon off and  button it back up and ride it. 10,000 is hardly broken in for the cared for ones, others it's pastured and  shot full of holes.

[Muddyape]

Sounds reasonable.....just had a heart attack couple of months ago (@38 yrs old) and been home going crazy looking for something to do while I recoup figured since its snowing and 20 degrees out I'd lock myself in the basement. I appreciate the advice but she's coming apart. So any suggestions on getting this cylinder off?

[wrenchmuch]

I can understand the need to know its all clean and happy inside your engine  . At this age the rubber engine internals (tensioners ,guides , seals ) are hard . As the engine runs it will beat bits of rubber off things like the camchain guides . Replace these parts while your in there . If the head is good why swap it out for a later one ? Unlike the 750 the cam bearings in a 550 are integrated with the head . Can't imagine the would be a lot of wear on them at 10000 MI . Sorry can't help with the barrels .
Heart attack at 38 . God bless you , hope your on the mend .

[Muddyape]

Thanks. Just saw a thread about this Cam bearings on here and didn't know if it should be addressed or not. Leave it alone I guess. As far as seals etc. I'll take care of those too. The heart attack was a "bump" in the road and motivated me to start this project. Got to realize that anything can happen at any given time so waiting for things to just come along is no longer an option. Live for today. Im an 18 yr veteran of a police department in Massachusetts version of Dodge City with 6 yr old twins and a redheaded wife........."the perfect storm"

[faux fiddy]

My stuc bores were from stuck rings in the bores, which shouldn't be an issue with yours. I used a piece of hard delron plastic to start to beat on the top of the pistons, but yours should just turn if you want them to move.

I would make sure there is not some little flange under the carbs with a bolt or something like that you overlooked. Other than that , spinning the motor and muscling  the bores to rock back and forth, and maybe finding a putty knife or something  to gently prise into the gap. Maybe a plastic chisel like they use for falling trees?

Wish you a speedy return to 100% and  better health in the New Year.

[Elan]

the cam chain would usually be the next thing to go , z1 enterprises sells a heavy duty replacement one.  may want to measure the primary chains to see if they are anywhere near stretched. Do you have the bible i mean workshop manual?  its available for download on this site.

[faux fiddy]

the cam chain would usually be the next thing to go , z1 enterprises sells a heavy duty replacement one.  may want to measure the primary chains to see if they are anywhere near stretched. Do you have the bible i mean workshop manual?  its available for download on this site.

Aha! , and, but of course. That hidden bolt is on the cam sprocket.

Here are some reassembly  photos of a 550 I refer to for the 350 camshaft. The'yre close enoughto the same procedure.

http://forums.sohc4.net/index.php?topic=369.msg57914#msg57914