Topic: '78 CB550 Refurb-O-Mod!

[BradyN]

EDIT: removed the broken photobucket links
I've decided its finally time to stop stalling (no pun intended) and get going on this project. Here's my '78 CB550K:
*snip*
Overall, not too bad. It runs pretty well, as far as I can tell. Last year I rebuilt the front caliper with a new seal/piston and pads but did not change the lines. They work fine, but squeak TERRIBLY. I also patched the exhaust holes as best I could. I just bought a parts bike toorecently, a '75 I think:
*snip*
 No title, and it doesn't run, but look at those cool wheels! I should really just call it a "wheels bike," because thats really why I bought it. That and another disk and caliper, and any other parts I might need that I haven't thought of yet.

Anyway, my plans for the 78 550 so far are:
 - 3K mile service
 - change bars to 400F bars, and hopefully run the cables inside the bars
 - rebuild those Lester wheels (if they even fit on my bike!) and use them
 - add a second caliper and steel braided brake lines

First things first though, I want to be able to start my bike without hotwiring it. Last season my ignition stopped working suddenly. I managed to pull it out today and look it over.
*snip*
That's as far as I could break it down, but I couldn't figure out a way to get it apart further without breaking it. I spraying in with de-oxit but it still doesn't seem to work. I guess the best option is to get a reproduction one?

Also the block connector that plugs into that is a bit melted from using bits of wire as my 'key' last fall, is this a obtainable part or should I just clean it up and reuse it?

I also read that cleaning the electrical connections is a good thing to do on these bikes. So I pulled the headlight out to see what was in there...
*snip*
Then I screamed in terror and stuffed it back in there, haha. Its actually not too bad, the plastic covers are dirtier than the actual bullet connectors, which looked shiny and clean on the ones I pulled. Eventually I'll get into there in more detail and see if everything is alright. The only thing that jumps out at me is a female bullet connector on a brown wire that isn't connected to anything.

Most of what I'm doing is probably very basic to all of you, but this is my first time working on a bike so its pretty overwhelming. I'll try to search for any answers that I need before asking here, but I'll post my progress just in case other people are trying the same things or are curious. Thanks for checking it out.

[SOHC4 Cafe Racer Fan]

Those Letters will fit on your later 78 550.  The bonus is that you have the rarer 18" rear Lester (versus the 16").

[BradyN]

Those Letters will fit on your later 78 550.  The bonus is that you have the rarer 18" rear Lester (versus the 16").

Okay great, I wasn't sure because I read the earlier 550's used different swing arms. Anyway thought it would be worth scooping up because of the 18" rear.

[Bankerdanny]

I have those same wheels on my '75 550F, they are the main reason I bought the bike.

The swing arms might be different, but the spacing and axle sizes are identical, so the wheels will bolt right up to your '78.

You should consider swapping the carbs, intake runners and airbox from your parts bike to the '78. The earlier carbs are a bit easier to work on and for some reason rebuild kits for the PD series carbs are harder to come by. The '78 PD's were also the leanest setup of all the 550 models, so you might pick up a small amount of extra power with the '75 carbs, although I never felt like my '77 550K was underpowered.

[Bankerdanny]

Oh, and there is a really good thread out there on rebuilding the switches on 550F's and 77-78 550K's http://forums.sohc4.net/index.php/topic,74213.0.html

This is a known failure point on the 550's with the factory switch between the gauges. Hopefully the pictures are still there. I am at work and pictures from the various hosting sites are blocked, so when I reviewed the thread all I saw were x's.

[BradyN]

I'm going to have to get a new exhaust at some point (unfortunately) because mine is mostly made of rust and JB Weld, that might be a good time to switch carbs. I read that the earlier ones are easier to adjust, do you think they'd make a noticeable increase in power, along with a 4 into 1 exhaust? How difficult would it be to get the PD carbs running *well* with a new exhaust?

Oh, and there is a really good thread out there on rebuilding the switches on 550F's and 77-78 550K's http://forums.sohc4.net/index.php/topic,74213.0.html

This is a known failure point on the 550's with the factory switch between the gauges. Hopefully the pictures are still there. I am at work and pictures from the various hosting sites are blocked, so when I reviewed the thread all I saw were x's.

Thanks for the link! That switch looks slightly different than mine, which makes me think mine might not be original. There's no easy way to crack it open, but I might just pry at it seeing as I'll have to replace it anyway.

[BradyN]

I just ordered repro ignition switch from 4into1.com. After comparing the pictures they have of the switch to mine, it looks like I already had a repro switch in there. It's a bit different than the one in the link about repairing the original switch. After reading a few threads about these switches, it seems they fail pretty easily because they can't deal with the current through them too well. I'm going to look into hondaman's relays for the ignition switch.

[BradyN]

Well I finally got a chance to start on the 3K mile service today. Things didn't go so well :/ But I got some new tools!

I decided to start with valve tappet adjustment. It took some prying to get the ignition cover off, looks like it was sealed on there with this black sealant:


Do I need to re-seal it, or can I leave it as is?

I was a bit confused over setting the valves, seeing as there are 2 pairs of marks. After a bit of reading it seems that the first mark is TDC of 1 and 4, ths second mark is the 'firing' mark of 1 and 4 (because it is a wasted-spark ignition) and the second pair of marks have to do with strobe timing, I guess? Anyway, I think I figured it out.

The valves all seemed very close to spec, but I was surprised to find that the tappet covers had a soft, rubbery silver-colored thread sealant on them and a harder black sealant around the edges. Here are some pictures to help describe it:

sealant:

leftover thread sealant:

When I took the tappet covers off the thread stuff got left behind on the threads but I was able to pull it out cleanly.

After I was done adjusting disaster struck.


The threads sheared off as I tightened the tappet. I was able to unscrew the broken thread easily, but that little chunk fell in. I tried to get it out with long tweezers but it fell deeper.

What do I do now? I guess I have to take the valve cover off and retrieve that piece?

[SOHC4 Cafe Racer Fan]

Unfortunately yes since it's aluminum and you cannot easily use a magnet on an extension.

[Scott S]

 Try some grease on a Q-Tip.

[Bankerdanny]

On the plus side the tappets are attached to the valve cover rather than the head and it can be removed with the engine in the frame, neither of which is the case with the 750. You can replace the damaged adjuster with one from your other engine.

[BradyN]

Thanks for the help guys.

Scott, I'll try the qtip w grease. If that doesn't work, I'll attempt to pull the valve cover. I tried the impact function of that screwdriver I got, but it kinda sucks. You have to push so hard I was afraid I'd push the bike over. I ordered another impact driver with interchangeable bits and I'll try again.

I think I'm going to try to remove the black gunk on the tappet covers and replace them with new orings.


Is there a gasket on the valve cover? If so can I reuse it?
edit: seems there's an orings seal there. If it's anything like the tappet covers there'll be a lot of sealant in there. I'm not going to order more parts until I crack it open.

[Ashdowner]

Steady with the impact driver. On mine I've replaced all the original cross headed bolts with cap bolts for an allen key. Might not be original but they make everything so much easier.

[Stev-o]

Subscribed. 

Remove all the sealant otherwise you risk another disaster - clogged oil passages in your motor [and possible seizure].

[calj737]

If you need replacement tappet covers, let me know. I've got plenty and they're yours free as a "House Warming" gift.

When you reinstall the tappet covers, the lightest smear of AntiSieze on the threads will help them release in coming years. Its aluminum-aluminum fit and that can be disastrous if galled.

If you decide to remove the valve cover, please first release the valve adjusters to avoid bending a valve. The rockers are fixed to the underside of the cover, and prying it off can cause an open valve to be bent by the added torque.

Don't fret the small stuff; you're on your way to a nice bike and these blood blister are part of the territory and make it all worthwhile. 

[BradyN]

If you need replacement tappet covers, let me know. I've got plenty and they're yours free as a "House Warming" gift.

When you reinstall the tappet covers, the lightest smear of AntiSieze on the threads will help them release in coming years. Its aluminum-aluminum fit and that can be disastrous if galled.

If you decide to remove the valve cover, please first release the valve adjusters to avoid bending a valve. The rockers are fixed to the underside of the cover, and prying it off can cause an open valve to be bent by the added torque.

Don't fret the small stuff; you're on your way to a nice bike and these blood blister are part of the territory and make it all worthwhile. 

Thanks Calj, I appreciate the encouragement. I ordered a tappet already when I thought this would take only a few minutes, but its proven to be a little more complicated just because I have to replace most of the screws. I might take you up on the offer if I break any more of these tappet covers when I tighten them down. I broke most of the screws on the head cover loose, but I'm waiting on the new fasteners to open the head. Also, I haven't been able to get the cylinder head side covers off. The small short screws are proving to be very difficult to remove.

Remove all the sealant otherwise you risk another disaster - clogged oil passages in your motor [and possible seizure].

I'll remove the sealant from the tappet covers and get new o-rings. I didn't order new gaskets for the breather cover or the valve cover, hopefully the old ones will be fine.

Had to grind slots into the screws to break them free:

Having serious trouble with these little screws, I haven't been able to get them out with the impact driver:

Under the breather cover. Looks like someone grinded at the holes there, but it might be just a rough casting clean up from the factory?

I noticed the chain master link clip was on backwards, so I pulled it off and cleaned it with kerosene. I pulled the sprocket cover and cleaned the area around the front sprocket. It looks pretty dirty, but this is after 45 minutes of scrubbing with kerosene. There was caked on mud and chain lube that was hard as a rock!

There's plenty of work for me to do while I wait for the new screws to arrive. I have to put the chain back on and adjust the chain slack (it was way off when I measured it), I got a new seat cover to install, and I still have to install the ignition switch. Its frustrating because I just want to RIDE this damn thing! But hopefully going over this stuff will be worth it.






 

[calj737]

The casting flash on the valve cover is normal. The end caps have a rubber o-ring under them on 2 dowels. Once you get the screws out, they can still be finicky to remove.

[BradyN]

Okay. My next idea to remove the end caps is to shoot PB blaster under the end cap, where hopefully it'll reach the threads of the screw. Then I'll file the edges of the screw head to mate with the impact driver bit better. If that doesn't work, I'll have to resort to more extreme methods...

I ordered new 6x3mm o-rings from "The O-Ring Store." Much cheaper than buying the official part for several bucks a piece.

[calj737]

Use a 3/32" drill bit, and drill the center out. Careful, that screw is short. Once you've done that, a left hand drill bit will turn it right out.

[RAFster122s]

May wish to put a relay kit on your ignition, as the EMGO ignition switches are not known to be ANYWHERE near as good as an original, it will handle the heavy load that would go through the switch between the feed wire and the red-switched power coming out of it...  That way your switch lasts.

David

[RAFster122s]

Be certain to use anti-sieze on the screws going back in...
Original screws can be had, or the kit from Yamiya if you are feeling flush with cash. They do carry the rare/hard-to-find period correct "8" bolts used on the early bike, if you want to keep the "8"s on the bike.  Otherwise a polished stainless bolt set from AlloyBolts on ebay is a good thing...
Forget if they use the id of AlloyBoltz insead of "Bolts".

David

[BradyN]

Use a 3/32" drill bit, and drill the center out. Careful, that screw is short. Once you've done that, a left hand drill bit will turn it right out.

I've never done this so I just want to be sure I'm understanding it correctly: Use the thin 3/32" drill bit to make a hole down the shaft of the screw, then a slightly wider left-hand drill bit to remove it?

May wish to put a relay kit on your ignition, as the EMGO ignition switches are not known to be ANYWHERE near as good as an original, it will handle the heavy load that would go through the switch between the feed wire and the red-switched power coming out of it...  That way your switch lasts.

David

Thanks for the tip. The ignition switch that died on me is one of the EMGO reproductions, so its clear they're not too reliable. I was thinking about getting Hondaman's relays for the switch and the cutout switch too. I just have to figure out how to mount it all up. I might wait until I switch handlebars. I managed to find bolts and screws at "Z1 Enterprises" for pretty cheap, but I had to get the two side oval screws and the longer flange bolts from Bike Bandit. The crush washers were actually the most expensive part. I could probably reuse the copper ones but they looked a little chewed up so I got new ones.

[calj737]

Use a 3/32" drill bit, and drill the center out. Careful, that screw is short. Once you've done that, a left hand drill bit will turn it right out.

I've never done this so I just want to be sure I'm understanding it correctly: Use the thin 3/32" drill bit to make a hole down the shaft of the screw, then a slightly wider left-hand drill bit to remove it?

Exactly.