1977 CB550 SS complete engine rebuild....going to need help I think...

Well, I took a project off a friend's hands and I paid far too much for it maybe. Or maybe not. Either way, he had fully disassembled the engine and had the cases blasted etc. So my dilemma is that I have cleaned up and honed, or had machined several top ends, and cylinder walls, heads, valves etc, but I have NEVER been into the lower end on any engine let alone any of my vintage bikes. So today is the day I start that journey, which is part of the reason I bought this pile of bike parts in the first place and DTT is the reason I wasn't too worried about it. I'll be referencing www.CMSNL.com and other parts microfiches to get this thing back together again. If I had torn the engine down myself I might be in a better spot, but he's got everything in bags and boxes and such so I'll take any help I can get with the transmission side of things and getting the cases properly sealed up as I've never had to do it before. Here's a picture of most of it. I'll get better pics soon when I have the room to spread out and pull everything out to find it all. If anyone has links to a cb550 rebuild from the bottom up, or any other good info/links I'd be very appreciative. This won't be a fast build as I'm quite busy cleaning carburetors for people and fixing up their bikes. But I figured it was time to get on this to bring her back to life. Thanks in advance. 8)

log you're progress here, especially when/where you get stuck so some of us can chime in. I just recently finished up helping GV1390 button up a rebuild on his 550 so it's somewhat fresh in both our minds and he has a spare motor partially apart for comparison too.

Awesome. I really appreciate it. To be completely honest, I'm really not sure where to start. As in, what's the first thing you bolt back into the cases???? He didn't loosen or pull any nuts/bolts from the crank rods so I should be able to just put that back in as-is (after checking bearing journals/spots to specs of course) I'll take pictures and log as much as I can so that if/when I get stuck, it will be easier to find out what I did wrong, or where something is missing

first thing I would do is get a bore gauge and watch youtube videos on measuring bore....then measure pistons....then figure out which ones best fit in which cylinder.

Then I'd put the crank/rods in, followed by trans, then the oil pickup and accessories, then pistons onto rods and jugs, head, etc.

Onboard Bruno. I've got one of these half apart right now too. My 550 build stalled when I picked up too many other projects. I have it all bagged and tagged but didn't go into the bottom end either.

Of course you have the manuals right?

all the manuals are on SOHC4.net for free to download...

Yep! got the manuals for the 500's and 550's although now that you say that, I'm not sure if the manual I have for the earlier 550 is the same as the 77. Most likely but we'll see. I'll start with the youtube and bore gauge or something I can measure with properly.

Canyon, this should be fun eh? haha. I'll try to get spread out tonight and started so I can document it nicely. Here we goooooo!!! 8)

Don't sweat it, the bottom ends on these old lumps are pretty simple. The trans is the most complicated part and even it's insanely simple once you get down to it. As stated I'd start at the rotating assy and piston\bore combos after you've honed the jugs out. Order new cam and primary chains from tsubaki, may as well replace em, and consider the primary chain tensioner as well. Check your shift forks carefully for cracks or bends and inspect the dogs on your tranny gears for wear. Replace counter shaft and shift shaft seal and kicker seal too. Seal cases with threebond. Good luck and take your time.

Following along.

I'll follow along. I've got a 550 I'd like to tear apart this winter.

Sounds like a plan. I've had a 4x8 plywood piece (3/4" thick maybe) sitting on the side of the garage indoors for a while. I think I'll make that into a table to get this puppy going. I really need to pull things out to see where it all is! Here's some shots of the cases for now. Nothing looks bad to me. He said there was nothing wrong with the bike, he just pulled it apart because it was so dirty and he is anal about cleaning things. I've helped him get a couple of his clean machines up and running again since I know carburetors

Do you have the crank/rod bearings for it?

Good question. I have the bearing pieces yes, and I think he had the other bearings (just a ball bearing without seals on either side correct?) He's labeled them nicely in plastic bags. Here's the setup so far. Trying to separate everything out, and then put all of the transmission stuff on the left so I can get started on the build on the left side. I want to put a 1" strap of wood or something around the edge to help with any parts that may want to roll off or away from me. This is most of it though. Looking at the pistons makes me say that this wasn't in the best of shape before hand. Sides are all scraped up on a couple of them. So do I just ebay a set like this? And get a second jug for fun..haha. Let me know what you guys think. I'll get some pics of the pistons over the weekend and update Monday. I just remember thinking that I wouldn't run them for sure.

Or there's this on ebay currently : http://www.ebay.com/itm/76-HONDA-CB550-SUPER-SPORT-CB-550-HM169B-ENGINE-CYLINDER-JUG-TOP-END-PISTON-SET-/291379788594?hash=item43d796bb32&vxp=mtr

And rings: http://www.ebay.com/itm/Honda-CB550-CB550F-Piston-Rings-4-SETS-STD-Size-1974-1975-1976-1977-1978-550-/361308584015?hash=item541fab784f&vxp=mtr

They make good piston kits 1 over for these. I'm setting aside some parts cash for the same thing myself. Extra cost yes but extra horsepower for the effort.

How do the cam surfaces and rocker arms look?

I don't remember the cam surface off the top of my head, but some of the rocker arms had nicks or gouges in them. Although it really looked like a manufacturing "defect" rather than a scar from a chunk of metal or similar getting in there. I'll take good pics of those too.

Here's some pics. Looks like I'll need at minimum one piston. Cylinder walls don't look terrible, so I'm not sure if they were already "cleaned" up or what. Have to check the size. You can see the valve tappets are a little beat up (not sure if that's normal or not, but I don't remember it on my other top end cleanups) And there's one or 2 of the cam side of the tappets that are scarred or have some metal missing. I would think that I could take apart another CB550 head for those if needed, or replace the whole valve cover and tappets with an older model as well. But I'll check on that, let me know if that's wrong. Here's the pics.

Tappets are usually OK so long as you're able to back them out all the way. The rocker arms are also usually OK if you can run a finger nail along the follower and not have it catch on anything. The journals on the rocker box cover look pretty good.

Sonreir said:

Tappets are usually OK so long as you're able to back them out all the way. The rocker arms are also usually OK if you can run a finger nail along the follower and not have it catch on anything. The journals on the rocker box cover look pretty good.

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Awesome. Thanks. I'll check into that then. It seemed like it was missing metal from the factory versus something gouging it. The cam lobes all look fine and the surface they sit on does too, so maybe that's all good.

So is it wise to just get new chains, because I'm having a hell of a time to find a new Primary. The Primary chain is "obsolete" according to Partzilla and several others. http://www.partzilla.com/parts/search/Honda/Motorcycle/1977/CB550F%20A/PRIMARY%20SHAFT%20%2B%20CHAIN/parts.html

At least it's easy to find the bearings. Although what's up with 3 different part numbers?

From what I gather, I can start with the lower end, get the crank and transmission put back together and then deal with the pistons/cylinders after that is complete. Going to start looking at diagrams and find all the parts in the bags and get a move on. Going to consult the manual for the proper way to deal with the bearings etc. Hopefully nothing too crazy to do Chime in if you have secrets you are willing to give up!!

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look at the cogs on the side of the gears and the slots in the gears they mate with . . if the edges look shiny, it is ok, if they look rounded off, i would replace them.

if there are wear marks on the shift forks . . i would replace them.

if the forks have wear marks on the tip on one side and on the heel on the other, they are bent . . replace them . . also replace the gears they were riding on and look closely at the slots on the gears they were mating with.