1966 CB77 Restoration Project

Seadog · Post by **Seadog** » Fri Apr 20, 2018 5:15 am

Yes, a big improvement, I’m down to 0.001” now. What’s the norm?

G-Man wrote:A big improvement on what you had!

That last bit is the hardest.

G

Seadog · Post by **Seadog** » Fri Apr 20, 2018 11:11 am

I’ve read that the definition of insanity is doing the same thing over and over and expecting different results. If that’s the case, I’m certifiable.

I’ve found that I just cannot adjust the right side crank runout down to less than 0.001”. I’ll have to live with that. Having made that decision, I turned my attention to the left side, which was previously 0.002” off. After the sustained pounding the right side took, I found that the left runout is now less than 0.001”. I’m moving on.

G-Man · Post by **G-Man** » Fri Apr 20, 2018 12:40 pm

Seadog

That's probably the best you can get for practical purposes. I did get one side down to 0.0001 (yes 1/10 thou) but I lost that when I trued the other side.

The texts I have read say that the total runout (add the two sides) should be below 0.001 but that is maybe a little ambitious for the home workshop.

Great achievement though, considering what you started with!

G

Seadog wrote:I’ve read that the definition of insanity is doing the same thing over and over and expecting different results. If that’s the case, I’m certifiable.

I’ve found that I just cannot adjust the right side crank runout down to less than 0.001”. I’ll have to live with that. Having made that decision, I turned my attention to the left side, which was previously 0.002” off. After the sustained pounding the right side took, I found that the left runout is now less than 0.001”. I’m moving on.

Seadog · Post by **Seadog** » Fri Apr 20, 2018 2:19 pm

Thank you, G. I like paying attention to details, so I’m not overly happy about it, but it’s the best I can do, short of sending the whole crank out for rebuilding or buying a new one. At least the right bearing isn’t hopping around any longer. Hopefully, I’ll be dropping in the cam chain and closing up the cases this weekend.

G-Man wrote:Seadog

That's probably the best you can get for practical purposes. I did get one side down to 0.0001 (yes 1/10 thou) but I lost that when I trued the other side.

The texts I have read say that the total runout (add the two sides) should be below 0.001 but that is maybe a little ambitious fro the home workshop.

Great achievement though, considering what you started with!

G

Seadog · Post by **Seadog** » Thu May 31, 2018 7:38 pm

It's been quite some time since I updated this thread. Basically, much of the work is done, but i've yet to find a painter for the frame, so I'm stalled. I putter with refurbishing small parts, polishing wheel hubs, painting and the like. I've begun to think about my titled frame.

As a recap, I started this project with just a frame and went about finding a donor bike to flesh it out. The donor I found, although untitled, was so nice that I decided to title that frame and either sell or set aside the frame I started out with. I have since decided to make that another project, although a long term one, only to be seriously undertaken when this project is done.

I decided to just search for an engine, since it's the hardest bit to find, do any major work to it to get it ready and then set everything aside. I posted a wanted ad on Craigslist and, surprisingly, it actually yielded results. 2 nearby individuals offered a total of 5 engines. I bought 3 today.

The first, and most promising, is a partial 1966 CB77 engine. The serial number is only 263 lower than my frame number. I'm going to use that as the base. Unfortunately, it is missing it's lower crankcase, transmission and many small parts, but it does have the carbs, cam chain tensioner and points plate.

The second engine is, I think, a 1962 CB77 engine, serial 214196. The number doesn't fit with the engine number history chart, but I removed it from a frame with a 1962 wiring harness tag. It will provide me with many parts missing from the '66 engine, such as the crankcase covers, oil filter, oil pump, all of the kickstart mechanism, transmission, starter motor, etc. It also has carbs, but the earlier round bowl type, which i don't need.

The third engine is from a CA77. I've mostly stripped it down for parts. It has a good oil pump and transmission, and I'll probably use the bottom crankcase on the '66 motor. I'll be offering up some good parts from it, such as the carb and the right crankcase cover with all of the kickstart bits, cam chain tensioner, etc. If anyone sees anything they need in the photos below, let me know.

Of course, all of the engines are stuck. I've put the Dream bottom crankcase on the '66 engine for now and will be removing the head tomorrow to access the cylinders.

The '66 engine:

The '62 engine and the Dream engine:

Tearing down the Dream engine:

Bits and pieces:

'66 with the Dream lower crankcase:

Two '66 engines:

I have not yet come to a decision on the other 2 CB engines offered to me. One is a '66 or '67 (105xxxx) that's mostly stripped. The other is a CB head and cylinders on a CA crankcase. Also stripped of most of it's outside parts. i'll probably pass on them both.

Great fun!

G-Man · Post by **G-Man** » Fri Jun 01, 2018 1:51 am

Seadog

What a great find. That strange alternator cover is fetching good money (asked for anyway) on ebay so you might get some of your money back. Also - round bowl carbs are hard to find.

G

border0_3 · Post by **border0_3** » Fri Jun 01, 2018 3:15 am

Hi Seadog,

Great project, but be aware of CA - CB differences.

Sometimes different cases don't match. We had a gearbox that went tight when the cases were bolted up.
Using the 62 CB engine as the parts donor is the way to go.
The CA transmission is not the same as the CB. The ratios are different and meshing dogs are cut different.

Otherwise keep on building.

All the best - Richard