Topic: Dad's 1978 Honda CB550k

[joegeis]

While Mark's got my cylinders, my simple fork oil leak has turned into a whole front end job. Since I had the front tire off, I decided to get the fork lowers powder coated to match the wheels. I forgot to remove the bearings, so they got cooked and needed to be replaced. I went with All Balls this time, since I noticed a little greasiness on my fork tubes previously. Maybe these are better. I lost a circlip, so went ahead and replaced both of those. I finally got my spare oil lock piece. As I was getting everything cleaned up and reassembled, I found myself with three of them... I don't know what happened. The original must have been in my parts box the whole time and I just missed it. Ugh.

I also put on superbike bars, new grips and bar end mirrors. I had previously bought the 4into1 SS braided front brake line kit and a aftermarket master cylinder because my original one was seized so badly I couldn't rebuild it. Well, in order to get everything to fit on the smaller bars, I loosened the banjo bolt to adjust the angle of the brake line, and when retightening it I snapped the bolt! It took barely any pressure. It wasn't even secured to the bars yet. I was holding it in one hand! Cheap junk! Anyways, I didn't feel like trying to drill out the bolt from the MC and I didn't like the brake lever feel anyways, so last night I purchased a Nissin 14mm modern MC on Dime City Cycles. I' fine with the more modern look. In fact, I think it will go with my bar end mirrors. It just goes to show that there are no small and simple jobs!

What I thought would be a couple hours putting the front back together turned into most of the day and an extra $200 in parts... Anyways, here are some photos. I'll be cleaning up and porting the head and intake manifold today and lapping the valves and replacing the valve seals later this week. I'm almost certain my oil pan is leaking (or maybe its just been running down from my base gasket). Either way, I'll probably drop the pan since the exhaust is already off, replace the gasket and add some liquid gasket. I purchased Hondabond from Common Motor Collective, but they sent me Permatex Motoseal Gasket Maker 29132. I'm assuming this is the same stuff? I've also got some Permatex #2 on order from Amazon.

[BenelliSEI]

Joe…. looking good! With the head Brocken off that banjo bolt, it should come out easily. Jam anything in there (the right size easy out would be better) and it should turn almost freely?

[joegeis]

Thanks Benelli! No dice on that banjo bolt though. It's not budging! I have not yet invested in an easy out kit, and honestly I'm kind of excited about my pending upgrade anyways.

I did some work with the head today. I got the valves apart and started taking a brass brush to the valves and the combustion chamber (not sure what its called - but the spherical area where the valve faces are that's all carbon-y). My brass brushes are really fine/soft and not doing much work on the carbon unfortunately. How clean should everything before going back together? Of course I'll lap the valves so everything seats nicely, but is it important to get the valve stem, surfaces and chamber spic and span? Anything else I can use besides my soft brass rotary brushes that might work better but not damage anything?

Also, I severely underestimated how difficult it is to clean off the old gaskets and make the mating surfaces nice. I was using PB Blaster and a razor, but realized I was still lightly scratching the aluminum. I've orders some CRG gasket solvent, plastic razor/scraper tool a carbide scraper and some maroon scotch bright.

Finally i inspected my intake manifold to see how bad they lined up, however I think it actually looks pretty good. I can feel a tiny bit of a lip on each one, but much better than some of the photos I've seen around here. I'm also planning to do some pocket porting above the intake valve. I got my copy of Hondaman's CB550 book and some carbide bits and will give it a go later this week.

Here are a few photos, and a link to the album with more.

[grcamna2]

How do your valve guides feel Joe ?

[joegeis]

How do your valve guides feel Joe ?

fine I think. I didn't really pay attention when slipping the valve stems out. I'll give them an inspection with the flashlight. Valves all felt tight when removing. No wiggle or play and no damage as far as I could tell so far to the seats.

[HondaMan]

That old carbon should come off the valves OK with a rotary wire brush. 50 years ago I held them by their stems with 2 wood blocks (think: paint mixer stick, broken in half) and cleaned them with a wire brush in my trusty Black & Decker variable-speed electric drill (still have it!), then relapped them in their seats.

The stubborn carbon in the chambers will yield to a Swiss Army penknife's curved blade, nearly a perfect curve match (I have about 6 of those).
Sorry about the master cylinder's bolt, but you are not the first to report that - and not just for the Hondas, either .

I think "4into1.com" is crypto for "parts that failed inspection, sold anyway"...

[joegeis]

That old carbon should come off the valves OK with a rotary wire brush. 50 years ago I held them by their stems with 2 wood blocks (think: paint mixer stick, broken in half) and cleaned them with a wire brush in my trusty Black & Decker variable-speed electric drill (still have it!), then relapped them in their seats.

The stubborn carbon in the chambers will yield to a Swiss Army penknife's curved blade, nearly a perfect curve match (I have about 6 of those).
Sorry about the master cylinder's bolt, but you are not the first to report that - and not just for the Hondas, either .

I think "4into1.com" is crypto for "parts that failed inspection, sold anyway"...

so, safe to use some steel on the valves, as long as I don't go ham? Was the rotary wire brush you used brass or steel?

yeah, no more 4into1 parts for me!!

edit - I tackled the intake manifold with the dremel as practice before doing the porting. It was more forgiving than I expected and I got a good feel for it. I did both where it connects to the head as well as where the rubber boots connect. I used the cone shaped bit, a sanding flap wheel and a maroon scotchbrite sponge bit. Its a significant improvement! I'll do a modest bit of porting with my new dremel confidence, staying well clear of the valve guide later this week. My exhaust port  has so much carbon buildup, I'm not sure where to even begin. The head does not fit in my ultrasonic tank either, so I suppose I'll have to do a little work with a few brushed by hand and some PB Blaster. I do plan to wash the head in the sink with soap and water once I'm all done cleaning up the ports, chamber and gasket surfaces. I don't believe there is anything on the head that will rust, right?

I'll also go after the valves and chamber with a steel brush, knife and/or wire wheel. Oh yeah, and I've been chasing the threads on all the bolts and nuts, and soaking all the pieces in Evaporust and giving them a little WD40 misting. All my hardware should be good and refreshed for reassembly.

I forgot to ask this before, but does it matter if the valve assemblies go back where they came from? I labeled and bagged everything so it all goes back exactly where it came from, but wasn't sure if it mattered. I would like to throw all the valves in the ultrasonic cleaner, but they will get mixed up that way.

Before/after:

[grcamna2]

I always like putting the valves back where they came from 

[BenelliSEI]

Easy way to keep valves and stuff organized….

+1 to “back where they came from”.

[BenelliSEI]

My “valve cleaning” set up….. Scotch Brite and Varsol after a good scrape with a pen knife. Plastic tubing protects the valve stem and box cuts down on the spray. Wear an old shirt!

[grcamna2]

My “valve cleaning” set up….. Scotch Brite and Varsol after a good scrape with a pen knife. Plastic tubing protects the valve stem and box cuts down on the spray. Wear an old shirt!

Plastic tubing,then you install the valve in the drill press ?

[BenelliSEI]

My “valve cleaning” set up….. Scotch Brite and Varsol after a good scrape with a pen knife. Plastic tubing protects the valve stem and box cuts down on the spray. Wear an old shirt!

Plastic tubing,then you install the valve in the drill press ?

Yes.. clamp tight without risking damage if it spins.

[grcamna2]

My “valve cleaning” set up….. Scotch Brite and Varsol after a good scrape with a pen knife. Plastic tubing protects the valve stem and box cuts down on the spray. Wear an old shirt!

Plastic tubing,then you install the valve in the drill press ?

Yes.. clamp tight without risking damage if it spins.

I want to have a shop(I'm in an upstairs apt.)w/ a drill press,hopefully someday soon.
I imagine you can spot whether a valve is bent or not,using the drill press.

[joegeis]

Finally had a little time to get back to work on the bike. Last night I finished porting the intake and scraping off the old gasket from the head (still need to clean up the bottom end).

It's really hard to get a good picture, but how does my porting look? I was super cautious as I didn't want to nick the valve guides, but I focused on creating an even, concave round surface above the valve guide, removing any raised bump, and then feathering that out to the sides a bit. I also matched up the opening at the mouth just below the valve seat. I didn't really do much with the exhaust port, just cleaning up the opening a bit and removing any burs (which I think were mostly just carbon buildup).

Before / After



My picked up some CRG Gasket Remover, which made this process much easier. I soaked the hell out of it and tried to be as careful as possible with my razor. The plastic razors did absolutely nothing, not did the carbide scraper. Constantly swapping to fresh razors worked best, though I feel like I still have a lot of scratches and gouges. Once I had most everything off, I took a red scotchbrite and a wooden block and "sanded" the surface, using the gasket scraper fluid as lubricant, which helped remove any remaining adhesive. You can see quite a few scratches, and the scotchbrite left the surface with a bit of texture - its not a glass smooth surface, which I believe is a good thing, right? Also I used a straight edge and feeler gauges. There is a 0.004 gap at the center. Is this going to be a problem, or is that an acceptable tolerance?

[MauiK3]

Might want to get that head flattened a bit, I'm no expert but that might be too much. Others here know way more than I do.

[joegeis]

I'm picking up a granite slab off Facebook Marketplace today and I'll get some of that sticky sandpaper to wet sand it down a bit.

I was going through the reassembly steps in Mark's new book, and also realized I'm missing the valve spring seats on my valves, so I'm picking up those as well.



Finally, I'm working on removing my base gasket and getting that surface prepped. While that gasket came up more easily, it still needs quite a bit of work to clean up. However, with it on the bike and with the cam chain and posts still in the way, how the heck do you get a good, clean and flat surface??

[joegeis]

Ok, I got the head nice and flat using the granite, some 220g sandpaper and some oil to wet sand it. I couldn't even get a 0.002 feeler underneath, so success there. I also got the base gasket surface nice and cleaned up using the gasket remover, a razor blade and some red scotchbrite. While I was there I chased the threads on the studs. Remaining steps:

1. Lap the valves in
2. Thoroughly clean the head
3. Reassemble (I still need to go through everything and make sure I have all the washers and replacement gaskets. I bought a kit, but worry it might not include some things).
4. Install new brake lever and refill/bleed.
5. Drop oil pan, check it for damage and flatness, replace gasket and seal it up to stop the leaks.
5. Replace petcock with one that has an internal sock filter. Remove my inline filter.
6. Valve adjustment, set timing, tune carbs, etc.
7. Ride before the season is over!

[joegeis]

starting to reassemble things now. Two things:

1. I found all but one of my valve spring seats. They were still stuck on the valve guide. I'm only missing one, though I have a full set lost in the mail somewhere, and hopefully arriving soon. Regardless, I started reinstalling the valves (save the last one missing the seat). I got 7 of them done, then looked over and saw a pile of fresh valve stem seals, definitely not yet installed. First time was just for practice, apparently!
2. I think I removed the valve stem o rings when disassembling everything, somehow. I definitely do not see any o rings anywhere around the valve guides. I've done some digging and it sounds like these are not supposed to have been removed unless replacing the whole valve guide, which I am not doing. I have new o rings, but I do not see how to possibly install them. There doesn't seem to be anywhere for them to go. I didn't take any pictures of this when pulling the valves apart. Am I fine to exclude these? Should I just place them under the smaller seats? It's not clear where the heck these actually go...

Finally a couple questions - as I start to put the cylinders, pistons cam, etc. back together, am I fine to just coat things in engine oil? I don't have any assembly lube, but not sure its needed on the top end. I've read a lot of mixed messages using the search function here. Also, the base gasket and head gasket go on dry, right? I don't have any real concerns on damage or non-flat mating surfaces. My surfaces look good.

[joegeis]

I got all the parts in the mail and finally got the engine back together again. I put a good 8 hours into today. I got the carbs back on and I was trying to route and install all my cables. I know that because I swapped to shorter "superbike" bars (which I understand are similar to the CB400 bars), I knew the cables would be a little long. I figured they would still serve well enough for getting the bike running again and I could worry about shorter cables later, if I felt it was necessary. I got the clutch and choke cables done, and I'm struggling with the throttle return or "push" cable. While the pull cable fit as expected, the push cable seems like there isn't enough wire. I can't get reach the retention hook with the threaded bit. I've taken it apart and at the handlebars, made sure there were no kinks, and fully adjusted as much as I can. I feel like I'm missing something obvious... Please, save me. What am I doing wrong??

There are PD46 carbs, incase that matters.

[HondaMan]

starting to reassemble things now. Two things:

1. I found all but one of my valve spring seats. They were still stuck on the valve guide. I'm only missing one, though I have a full set lost in the mail somewhere, and hopefully arriving soon. Regardless, I started reinstalling the valves (save the last one missing the seat). I got 7 of them done, then looked over and saw a pile of fresh valve stem seals, definitely not yet installed. First time was just for practice, apparently!
2. I think I removed the valve stem o rings when disassembling everything, somehow. I definitely do not see any o rings anywhere around the valve guides. I've done some digging and it sounds like these are not supposed to have been removed unless replacing the whole valve guide, which I am not doing. I have new o rings, but I do not see how to possibly install them. There doesn't seem to be anywhere for them to go. I didn't take any pictures of this when pulling the valves apart. Am I fine to exclude these? Should I just place them under the smaller seats? It's not clear where the heck these actually go...

Finally a couple questions - as I start to put the cylinders, pistons cam, etc. back together, am I fine to just coat things in engine oil? I don't have any assembly lube, but not sure its needed on the top end. I've read a lot of mixed messages using the search function here. Also, the base gasket and head gasket go on dry, right? I don't have any real concerns on damage or non-flat mating surfaces. My surfaces look good.

Those O-rings in your gasket set (probably green ones?) go underneath the valve guides if they are being replaced with Honda's own OEM guides. That's not usually done, and it's always mystified my why they come in the gasket sets? Most of the aftermarket guides I have seen and installed don't have the grooves under them, so then they still don't get used. The 50/50 head is very easy on the guides, though, and they seldom need changing unless they got rusted or such.

[joegeis]

starting to reassemble things now. Two things:

1. I found all but one of my valve spring seats. They were still stuck on the valve guide. I'm only missing one, though I have a full set lost in the mail somewhere, and hopefully arriving soon. Regardless, I started reinstalling the valves (save the last one missing the seat). I got 7 of them done, then looked over and saw a pile of fresh valve stem seals, definitely not yet installed. First time was just for practice, apparently!
2. I think I removed the valve stem o rings when disassembling everything, somehow. I definitely do not see any o rings anywhere around the valve guides. I've done some digging and it sounds like these are not supposed to have been removed unless replacing the whole valve guide, which I am not doing. I have new o rings, but I do not see how to possibly install them. There doesn't seem to be anywhere for them to go. I didn't take any pictures of this when pulling the valves apart. Am I fine to exclude these? Should I just place them under the smaller seats? It's not clear where the heck these actually go...

Finally a couple questions - as I start to put the cylinders, pistons cam, etc. back together, am I fine to just coat things in engine oil? I don't have any assembly lube, but not sure its needed on the top end. I've read a lot of mixed messages using the search function here. Also, the base gasket and head gasket go on dry, right? I don't have any real concerns on damage or non-flat mating surfaces. My surfaces look good.

Those O-rings in your gasket set (probably green ones?) go underneath the valve guides if they are being replaced with Honda's own OEM guides. That's not usually done, and it's always mystified my why they come in the gasket sets? Most of the aftermarket guides I have seen and installed don't have the grooves under them, so then they still don't get used. The 50/50 head is very easy on the guides, though, and they seldom need changing unless they got rusted or such.

Thats good to hear, since I buttoned it all up today! Struggling with the throttle cables, but once I sort that out and reinstall the exhaust, I'll be ready to try and start it up again! Hopefully tomorrow.

[MauiK3]

Be sure to post some photos!

[grcamna2]

Be sure to post some photos!

Ride report 

[joegeis]

Ok, had a lot of family stuff to do today, so only minimal work on the bike. I basically took care of the "loose ends," added oil (important!), valve clearances, cam chain tension, throttle cables, air filter, bled the front brake, tested the front brake lever switch, gapped and installed spark plugs.

I think all I have left is to install the exhaust and try to start it up!

About the throttle cables - I don't know what was wrong. I took it all apart, made sure all adjustments were loose as possible, the reattached the push cable first, then the pull. Everything installed as it should and I adjusted the slack from there. No idea what I was doing wrong yesterday! I still have shorter cables coming though, There is too much slack in the line.

Here are some photos of how she currently sits:


New modern brake master cylinder. Brake feels great after bleeding it. Excited to try it on the road.


Brake line has a horizontal S loop, I'm concerned about. I'm going to get a solid line from the MC to the caliper and bypass the switch. I'll create a jumper to use the lever's switch. I tested it with some alligator clips today and it works.


Big swoop out on the throttle cables.


The oil I'm using, along with 2oz of ZDDP:


Mark's new book, next to my Clymer manual!

[denward17]

Looking good!

Is that oil JASO MA2 rated?

If not, you may have a slipping clutch.