Author Topic: Brian's 1977 CB550 Rebuild (Clueless) (Read 3458 times)

Gorms · « **on:** May 19, 2009, 03:52:48 PM »

I am the definition of the word noob and hope I havent gotten in over my head. I am going to attack this slowly and hopefully, with the help of all you guys, this project will be a fun learning experience that will leave me with a very cool bike.

This past weekend I went for a little drive and came home with two (!) 1977 cb550's, one of which is missing the forks and wheel assembly. The complete bike ran but was extremely dirty and had a leaking head gasket. Both tanks are rusted out. What did all this stuff cost me? $260. Not bad for almost two complete bikes. The plan is to build a cafe racer and pretty much rebuild/restore every piece on the bike.

The past few days I removed the wiring harness, lights, seat, carbs, cables and finally the engine. Today I started to break into the engine to replace all the gaskets, seals, bearings, and piston rings. Since I have two engines, I will be using the best parts from both to rebuild the engine with the case number that was originally in the bike that I have a title to.

I am very handy with a good set of tools but have never rebuilt and engine or a complete motorcycle. I am going to have many questions, the first of which are below. I bought the Clymer's manual but have yet to receive it. My first questions are:

1) Does the Clymer manual cover engine rebuilds? If not, is there a good manual on this?

2) Once the camhshaft is exposed, how do I loosen the timing chain tensioner so that the chain can be removed from the cam sprocket? I am aware of the two screws on the center back of the cylinder bank for this purpose but could not get the tension loose enough (I took the top bolt out and played with the bottom slotted and threaded rod but it only rotated a bit).

3) Any cafe builders out there, when the battery is relocated under the seat, the wiring harness is too short. Is one custom made?

Pics to come as soon as I upload them to photobucket.

THANKS!

Gorms · « **Reply #1 on:** May 19, 2009, 05:01:32 PM »

OK so I just found the 550 manual available for download from this site. All I can say is wow! Its got everything!

Hush · « **Reply #2 on:** May 19, 2009, 08:50:29 PM »

Welcome and happy building.....you promised pictures.....best get thembefore you start your rebuild...we wanna see that the finished product is better than the starter bike.

moham · « **Reply #3 on:** May 20, 2009, 10:04:56 AM »

My advice is three fold:

1) go to the FAQs and find/download/print the factory shop manual for your bike. I took a pdf of the manual to Kinkos and had them print it on thick card stock and put in spiral binding (~$35). This is much better than a bunch of loose pages and the thick stock stays in better shape.

2) take digital pics of every step of disassembly, following the manual.

3) bag and tag Everything! It may seem like overkill, but When I labeled bags, I cross-referenced the steps in the manual and took corresponding pics.

All of this has helped me tremendously with tear down and rebuild, so far. Good luck.

Gorms · « **Reply #4 on:** May 20, 2009, 07:19:22 PM »

Thanks for the tips. Here are a few picture of the breakdown of the bike. Some pictures of the rocker and cam are still on the camera and I am out of town. Like I said, I have two engines, one of which I believe has 16k miles so I will build the best motor I can from the parts of both. I will be posting pictures and I will ask you opinions about the condition of the rockers, cam, cylinders, pistons, etc. The rockers of the engine I opened do look a little worn and one has a worrysome pit that I will detail. I have been putting things in bags religiously and one thing I have learned is to not only label the bag but also a piece of paper in the bag because even permanent marker wil rub off sandwich bags.

As to the manual. I printed it off before I left (all 188 pages). Im going to put them in page protectors to keep the grime on my hands from ruining them, and put them in a binder.

Gorms · « **Reply #5 on:** May 24, 2009, 09:00:06 AM »

So I am finding that '77-'78 carburetor rebuild kits are pretty much non-existant except through genuine honda parts, which are pricey. The '76 and earlier kits I see include not only gaskets but float needles and jets. Are these parts necessary to replace also? I can buy just the carb gasket kit through honda for about $12 per carb. Is that all I need if I thoroughly clean the other parts?

BlindJoe · « **Reply #6 on:** May 24, 2009, 11:27:34 AM »

yeah, just clean them good and get the gaskets

TwoTired · « **Reply #7 on:** May 24, 2009, 02:55:50 PM »

If the metal parts inside the carbs are not corroded, or damaged, they are quite reusable with a simple cleaning.

Gorms · « **Reply #8 on:** May 24, 2009, 03:33:23 PM »

Thanks guys, good news. Just got the pistons off the con rods which was easy enough. The manual say the next step involves using pullers to get the generator and primary shaft out. I dont have those tools so I guess I will orde them right? Any other way? The engine is pretty filthy so in the meantime I will do some cleaning up.

The plan is to disassemble the other engine and compare the wear on the parts. The rockers on this one has a pit on one of them. I really dont want to take the con rods off the crankshaft if I dont have to. Is that ok for an engine that has 38K miles? Im assuming the other engine has less than this so if I can use that crank, I will.

Oh and any tips on lossening the clutch bolts without letting the crank spin, especially now that I have the con rods exposed and dont want them falling into the case? Also, what are good tools/solvents for getting gasket material off the mating surfaces?

moham · « **Reply #9 on:** May 24, 2009, 10:02:23 PM »

Quote from: gorms on May 24, 2009, 03:33:23 PM

Thanks guys, good news. Just got the pistons off the con rods which was easy enough. The manual say the next step involves using pullers to get the generator and primary shaft out. I dont have those tools so I guess I will orde them right? Any other way? The engine is pretty filthy so in the meantime I will do some cleaning up.

I bought the generator puller from a local Honda shop for about $7 (the manual has a part no. for it) and it worked perfectly. I think other guys have used an engine mount bolt but I'm not positive on that...You can tap out the primary shaft with a brass or other soft drift. Just go slow and easy and it should come out alright. I tried making a slide hammer and it worked a bit but was more hassle than just tapping it out.

Quote from: gorms on May 24, 2009, 03:33:23 PM

Oh and any tips on lossening the clutch bolts without letting the crank spin, especially now that I have the con rods exposed and dont want them falling into the case?

Whenever I was trying to keep the shaft from spinning, I just took an oak dowel and shoved in between the case and the crank shaft. Again, go slow and easy...

Quote from: gorms on May 24, 2009, 03:33:23 PM

Also, what are good tools/solvents for getting gasket material off the mating surfaces?

I used a window scraper razor blade (using much caution and a light hand) and some spray-on gasket remover (not super effective) and a plastic putty knife (pretty much useless) and a metal putty knife (caution again). Pretty much just very slow, painstaking work because you don't wan to mar the mating surfaces of the cases. Other folks will have other tips...

Gorms · « **Reply #10 on:** May 28, 2009, 01:07:28 PM »

The "parts" engine looks so much nicer than the running engine that I am bringing it to a firend's to have it compression tested tomorrow. The running engine has liquid gasket all over it (been taken apart before) and some screws are stripped. It also has 38K miles. The "parts" engine looks much better, isnt leaking as far as I can see, and may have 18K on the clock as the odometer of the bike it came out of reads this.

What is worrying me is the exhaust valves on both engines. They look pretty bad to the untrained eye. The first 5 pictures are from the 38K engine which I have semi-apart and the last 4 are from the parts engine. Are they as bad as they look?

Gorms · « **Reply #11 on:** May 28, 2009, 03:30:51 PM »

I did some sraping/light sanding on the valve of the disasembled engine. It looks like the corrosion is built up the valve, obscuring the letter "E" and some slots on the face of the valve. Does this mean its just a build up and the valve is fine underneath? I also compressed the valve springs slightly and found that the mating surfaces of the vlaves are relatively smooth and shiney. Slightly speckled with borwn spots but it looks more or less like some good mating is going on between the valves and the seats. Hopefully the test on the complete motor will come back good. If it does do you think I should just run the engine?

I do have big plans for this cafe build but want to make sure I have a good engine before ordering thousands of dollars in parts. I want this engine to last a long time in a bike that is complete. If down the road I need a rebuild, I would have the time and cash to do that.

Hush · « **Reply #12 on:** May 28, 2009, 03:41:55 PM »

Not sure why you are stripping the motor down to it's base parts Gorms but hey it's your build.
I use a trailer tie down the kind with a ratchet attachment to hold my rotor on the left side of motor, to remove rotor just use either one of your back axles or a bolt of the same size/thread, keep winding till it pops off.
I wrapped the tiedown around the rotor a few times then around the riders foot rest bracket and cinched it up to hold it.

Gorms · « **Reply #13 on:** May 29, 2009, 02:07:41 PM »

The compression results are in:
145psi, 105psi, 145psi, 150psi

Sounds like the 145 numers are high (carbon buildup?) and the 105 is low. Can anyone shed some light on these numbers? Guy said maybe a valve adjustment may bring the 105 up. Might invest in a compression tester...

He also said that I should just run the engine. If you guys agree, I will talk to Benjie at BCR and get my tank and seat ordered. I need some reassurance though. Please chime in.

Gorms · « **Reply #14 on:** May 29, 2009, 02:11:09 PM »

Also, this engine has been sitting for who knows how long so maybe I should get it running outside the bike (thats OK right?) and run it for a few min, adjust the valves, and test again.

TwoTired · « **Reply #15 on:** May 29, 2009, 02:24:24 PM »

Compression tests are for in service engines where all the parts are comfortable with each other. Dormant parts become estranged. With the engine stopped, at least a couple of valves have not be resting on their seats,and my not return to full seall until have some wear occurs.

Run the engine for 50-100 miles. Test compression when the engine is hot and all the metal bits have expanded to fit together best.

Absolute numbers are only valid for a specific test apparatus, as the volume they add to the chamber varies with the manufacturer. Just look for numbers within 10% of each other.

I can't tell from your pictures whether you have rust on the valves or if that is oil deposits. Suspect the latter. Replace all the valve guide seals.

Gorms · « **Reply #16 on:** May 29, 2009, 02:43:44 PM »

Thanks. Good point about the fact that the valves would not be seated during storage. Maybe the valve on the 105psi cylinder was raised. Unfortunately I cant run the engine for 50-100 miles because the bike is in peices.

Gorms · « **Reply #17 on:** May 29, 2009, 08:37:42 PM »

Question:

Are the spokes the same for all years of cb550's? I have a '77 and if they are the same, I can get spokes for $80 on ebay vs $255 from honda.

Gorms · « **Reply #18 on:** May 30, 2009, 05:21:55 PM »

^^ Anyone?

moham · « **Reply #19 on:** May 30, 2009, 08:51:37 PM »

Check part numbers...

Gorms · « **Reply #20 on:** May 31, 2009, 09:48:42 AM »

Part numbers differ. Is that definitive? Ebay ad says they will fit cb550K but thats not good enough for me since I have a '77. It would really be nice to find a source that list all the differences between cb550 model years.

News:

Author Topic: Brian's 1977 CB550 Rebuild (Clueless) (Read 3458 times)