1963 CB77 SuperHawk

MILLENNIUM FALCON

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Hello, I am working on this Super Hawk for a gentleman that saw a bike I was selling on craigslist. Its in pretty decent shape! Within 1 hour I had it running. His goal is to get it all sorted out and return it to mostly original condition. I will try to post updates on here as I go along. He has boxes of parts. the bike is mostly complete. Eventually he wants me to paint it to look original.

 
Cool project.

First restoration I did professionally was a CB77 way back in ... long time ago. Last one I restored was a couple of years back.

That one is a very later production build with alloy fork legs and the seat was different to earlier ones in that it had a slight "bump" at the tank. Those may be early style mufflers and the seal should be inside that raised ring around the front end of the muffler IIRC.

Somewhere around here I have a CB77 race project that I should dig out and see what needs to be done to it.
 
interceptor said:
Jeez, how many bikes do you have ;)

Don't think of them as bikes, but as "potential Bikes" aka projects. And at last count Way TF too many for one lifetime.

Projects
1 CB160 road bike - Exhaust to redesign
2 CB160 race bikes - need to be built
1 CB77 race bike - Needs a fuel tank and pistons
1 Dunstall GT750 -Finished - Needs to be sold
1 reed valve custom framed GT750 - too much work - not enough time
1 TL1000 suspension GT750 - tank is in "the body shop"
1 GT750 drag bike - Frame never came back from major surgery to move the motor forwards
1 RD350 drag bike - Modifying the swingarm now for wheelie bars
There are others I think - if I can find them.. :)

Plus the bikes that are already running.... That's why I don't have a life or any cash or free time.
 
teazer said:
Cool project.

First restoration I did professionally was a CB77 way back in ... long time ago. Last one I restored was a couple of years back.

That one is a very later production build with alloy fork legs and the seat was different to earlier ones in that it had a slight "bump" at the tank. Those may be early style mufflers and the seal should be inside that raised ring around the front end of the muffler IIRC.

Somewhere around here I have a CB77 race project that I should dig out and see what needs to be done to it.

I'm far from an expert on CB77s but I also have one waiting in the wings. Shouldn't a 1963 CB77 speedo run counterclockwise? If the forks are from a later bike, that might explain it -- IIRC the speedo drive at the front wheel is specific to the ones that run counterclockwise.
 
teazer said:
Don't think of them as bikes, but as "potential Bikes" aka projects. And at last count Way TF too many for one lifetime.

Projects
1 CB160 road bike - Exhaust to redesign
2 CB160 race bikes - need to be built
1 CB77 race bike - Needs a fuel tank and pistons
1 Dunstall GT750 -Finished - Needs to be sold
1 reed valve custom framed GT750 - too much work - not enough time
1 TL1000 suspension GT750 - tank is in "the body shop"
1 GT750 drag bike - Frame never came back from major surgery to move the motor forwards
1 RD350 drag bike - Modifying the swingarm now for wheelie bars
There are others I think - if I can find them.. :)

Plus the bikes that are already running.... That's why I don't have a life or any cash or free time.
Wow! Sorry, didn`t mean to go off track ::) Back to the regularly scheduled program...
 
Yeah I am no expert on these bikes... This is the first one I have worked on. The guy told me it was a 63' i havent looked up the numbers yet. Not sure about the speedo. You guys know more than I do about these hondas. I went through the carbs today. They were spotless, as it the tank! I put new fuel lines and filters on it. I also gave it new plugs. It will start right up with the button, but the left cylinder keeps cutting out. After 30 seconds of running the temp gun says the right header is 250 degrees, but the left one only gets to about 130 degrees. It appears to have good spark but so I need to figure out what is going on there. Whatcha think... Points? coil? It has a new spark plug and the condition does not change if I spray fuel in the intake on that side so I doubt its a fuel issue.
 
MILLENNIUM FALCON said:
Yeah I am no expert on these bikes... This is the first one I have worked on. The guy told me it was a 63' i havent looked up the numbers yet. Not sure about the speedo. You guys know more than I do about these hondas. I went through the carbs today. They were spotless, as it the tank! I put new fuel lines and filters on it. I also gave it new plugs. It will start right up with the button, but the left cylinder keeps cutting out. After 30 seconds of running the temp gun says the right header is 250 degrees, but the left one only gets to about 130 degrees. It appears to have good spark but so I need to figure out what is going on there. Whatcha think... Points? coil? It has a new spark plug and the condition does not change if I spray fuel in the intake on that side so I doubt its a fuel issue.

I would check fuel flow first. Drop the float bowl -- is it dry? If so, you might have a bad float valve or sticking floats. The float bowl gaskets on these can expand and make the floats stick, so it'll fill up with gas, then the float sticks and no more gas gets to it. If you're getting good spark, it's almost certainly a fuel issue.

But you should also: adjust valves (when dead cold), check and adjust point gap, check and adjust timing and advance to make sure all those things are correct.
 
The wiring harness generally has the year of manufacture on it. That's a nice late 60's custom and a good bike to put back on the road. I haven't owned a CB in many years, but I have two 1963 CL250 scramblers. One of them has a 305 motor in it.
 
Both carb bowls are full when I pop them off. When the bike is running on one cylinder...if I spay ether in the dead side nothing happens that is what makes me feel it an ignition problem. I do need to check the valves... Point gap is good. I still need to check timing/advance. I need to find a good write-up on timing for these bikes. I dont have the manual yet.
 
Earlier bikes had different speedo/tacho combo and different drive.

130 degrees is very cold and suggests low compression or lack of spark or maybe really retarded timing on that side. Check the points gap on both sides first and then set the timing so that it sparks at the LF and F marks on the rotor.

Are both choke plates lifting correctly and do both slides open together?

What is the frame number and engine number (use xxx as the last 3 digits). It is probably after CB77 -1034092

How clean are the carbs? I mean the tiny drillings through for air and fuel? Try spraying carb cleaner through one passage in one carb and repeat on the other and compare the way they flow. Repeat on every circuit.
 
Ok, still cant get the left side to run.... The carbs are spotless. All new brass. Air screw set to 1.25. No idea on float hight but the bike "used to run great" :) Valve clearances were perfect, Point gap is set, compression is 158 on the right, and 153 on the left. I have strong looking spark on both sides when I crank it with a plug clipped in to view. Left pipe still barely get warm while right pipe gets nice and hot. This has me baffled. Spray ether in the left carb nothing changes... when pull the left plug wire nothing changes... when I pull the right plug wire the engine immediately dies. When I put the timing light on it... the line is right between the L & F. I need to find a source on how to set the timing...unless y'all can tell me. Thanks!
 
In my limited experience, if you spray starter spray into the carb and you notice no difference, then it may be an electrical/ignition problem. I have cut off a little of the end of the spark plug wire and then screwed the cap back on and it fires right up. Have you checked for spark on that side? -- I was just involved in a post on here where the same thing was happening to someone. It ended up being a bad/corroded connection
 
Thats what I was thinking. Yes, I do have spark.... not sure If its good spark or not, but it looks good with a plug clipped in when I crank over the engine. Could a weak coil be the problem? is there a way to test it?
 
Can you swap the coils easily? If the problem follows it to the right cylinder then you have your answer. You can also swap the plugs or substitute a new plug.

Like someone mentioned the wire is suspect. The screw caps can loosen just enough to be positional- that is, you get spark with it out of the head but none once you move it. Like mentioned cut it back an inch and make sure the wire you have inside is not corroded/green.

Another consideration- the wire is shorting. Again it could be the fact that it's ok when the plug is out but when you bend it with the plug in it's shorting to something close by. Easy way to check wire/cap is to drag a test light along the length of the wire. If there's a break you'll see sparks. A test light can also be used to check if you're getting spark- simply slip a small section of vacuum hose over the top of the plug and into the cap. Vacuum hose has carbon in it and will conduct. If you're getting spark a test light probe will draw a spark out of the vacuum hose as the bike runs. Again it could be useful to test a possibly positional setup.




Here's where I list all my bikes:
'71 Kaw 250 Bison
'81 KZ750 cafe
'94 XR250L
2014 Yamaha Bolt

In progress: '68 CL350
 
MILLENNIUM FALCON said:
... when I pull the right plug wire the engine immediately dies. When I put the timing light on it... the line is right between the L & F. I need to find a source on how to set the timing...unless y'all can tell me. Thanks!

That's not right..I don't have a CB72/77 rotor here, but doesn't it fire on the left side at LF just before LT (Top dead center) and the right at F? If the points cam is upside down that could happen I guess. Doe the timing light fir at all if you put the inductive clamp close to the coil?

You could also disconnect the blue and yellow leads from points to coil and swap the HT leads and see if it fires on left or right side.

That would tell you if it's the coil or the points and condensor.
 
Well I put a new set of points on it and clipped about 1/2" off the plug wires at the plug end and the coil end...... Now it is running on both cylinders but wont idle. I Rode it around the house a few times and its was smooth and had decent power but it would die as soon as I let off the throttle. So I guess Im making progress. It wont start unless I give it a bunch of throttle.... Air screw is at 1.5 turns... Needle is 2nd clip from the bottom. and both needles protrude about .045 from the bottom of the carb... Im guessing the carbs are out of sync or something.... Not sure. :/
 
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