Author Topic: 1976 550K Project  (Read 23994 times)

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Offline Stev-o

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Re: 1976 550K Project
« Reply #25 on: October 05, 2014, 04:01:23 PM »
Bet your pilot jets in the carbs are clogged.
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline mrfish2

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Re: 1976 550K Project
« Reply #26 on: October 05, 2014, 04:06:39 PM »
Bet your pilot jets in the carbs are clogged.

One of the pilot jets i cleaned completely, even with guitar string, and the other 3 i had to replace. I used Napco rebuild kits, they're made in Japan.

And no, I haven't done everything in the 3000 mile service yet.
1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.

Offline goldarrow

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1976 550K Project
« Reply #27 on: October 05, 2014, 04:10:04 PM »
What size are your pilot jets? And what do they look like?
Life Is Full Of Challenges - And My Backyard Is Full Of SOHC4's

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CB750 K0, K2, K23 JDM, K45, K5
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Offline mrfish2

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Re: 1976 550K Project
« Reply #28 on: October 05, 2014, 04:22:27 PM »
They're #38, stock size. The only difference I could find between the new ones and the old ones were the size of the holes in the stem. The only reason I replaced them was because I couldn't get the guitar string to go all the way through, it kept getting stuck so they were clogged pretty good.
 
1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.

Offline Stev-o

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Re: 1976 550K Project
« Reply #29 on: October 05, 2014, 06:45:43 PM »
Bet your pilot jets in the carbs are clogged.

One of the pilot jets i cleaned completely, even with guitar string, and the other 3 i had to replace.


Ok,  lost that bet.  Have you checked your spark advancer?
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline goldarrow

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Re: 1976 550K Project
« Reply #30 on: October 07, 2014, 08:26:20 PM »
So what have you done on the maintenance list? Valves check, ignition timing check, etc...
Life Is Full Of Challenges - And My Backyard Is Full Of SOHC4's

CB550 K0
CB750 K0, K2, K23 JDM, K45, K5
And the little ones z50r, xr50r, st90


750k5 http://forums.sohc4.net/index.php?topic=114817.0

Offline mrfish2

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Re: 1976 550K Project
« Reply #31 on: October 30, 2014, 12:43:07 PM »
Sorry been pretty busy with school, but checked the timing and adjusted the points last week and got another chance to mess with it again today. Put some more fuel in the tank and she fired right up but had gas pouring out of the #3 carb. Must have a float sticking. It was weird because it didn't take long for it to idle fairly decently. Maybe it was just the points haha.

Question: when I rev it up it hangs up when I let off the throttle, like say I rev it up to around 5k it'll stay around 3-4k for longer than it should before dropping back to idle. Thoughts?
1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.

Offline mrfish2

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Re: 1976 550K Project
« Reply #32 on: November 09, 2014, 04:10:00 PM »
Figured out it was a vacuum leak around one of the carb boots.

Spent the past couple days installing clubman bars and I have to say all that time spent routing the wires through the bars was well worth it. Took the front turn signals off too as they were in the way of the clubmans and aren't required in NC anyways. I'm putting the rear fender back on as soon as I get some more time to clean it up real good. Shorter throttle cables are on their way (ordered some from 4into1.com that are for a 400F but are about 5 inches shorter than the stock 550 cables so they should work well with the clubmans) along with a new chain and sprockets. After all that is installed all that's left is rebuilding the the master cylinder/caliper (I've been putting that off for a while) and a set of tires and she's ready to hit the road. I know you guys like pics so here ya go




1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.

Offline Slinky

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Re: 1976 550K Project
« Reply #33 on: November 10, 2014, 08:07:49 AM »
nice man, looks really good!

Offline mrfish2

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Re: 1976 550K Project
« Reply #34 on: November 15, 2014, 03:08:16 PM »
Finally had some time to rebuild the forks today with new seals and new oil. It's amazing what some Simple Green, a brass brush, and some elbow grease will do.




But now he looks kinda pitiful without his shoes on



Any advice on getting this old inspection sticker off?

1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.

Offline calj737

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Re: 1976 550K Project
« Reply #35 on: November 15, 2014, 03:16:17 PM »
You can try Denatured Alcohol. Maybe Acetone. Or, burn it off with a torch if you haven't already rebuilt your forks. Wouldn't want to heat the lower with new seals in there  ;)
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline mrfish2

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Re: 1976 550K Project
« Reply #36 on: November 20, 2014, 02:41:45 PM »
Routed the new throttle cables today and ran into a little problem. The length of the 400F cables I ordered fit perfectly with the new clubmans, but the Push cable's end was too big to fit into the right hand controls (see below).




Took the dremel to it and ground around the edge to make it fit. Didn't take much, but I figured I would post this on my build thread in case anybody else orders these cables for their bike.


1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.

Offline mrfish2

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Re: 1976 550K Project
« Reply #37 on: November 26, 2014, 11:32:33 AM »
Finally got the brake piston unstuck

Old brake pad


Rust in the caliper assembly
1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.

Offline calj737

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Re: 1976 550K Project
« Reply #38 on: November 26, 2014, 01:53:12 PM »
Soak that baby, then re-assemble.
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline Stev-o

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Re: 1976 550K Project
« Reply #39 on: December 07, 2014, 08:05:21 PM »
I've seen a lot worse.  Remove the seal and clean that groove til it's spotless.  Install a new seal.
Good time to paint the caliper too...
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline mrfish2

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Re: 1976 550K Project
« Reply #40 on: December 07, 2014, 08:14:02 PM »
I'm actually surprised how clean some parts are on this bike (besides all the rusty chrome). I'm getting some Dow Corning grease in the mail this week so i can finish up the brake rebuild, and I've already got a new seal and piston. Got the new tires mounted yesterday as well. I should have this thing on the road by Saturday (after 22 years haha) and I'll post up some pics too.
1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.

Offline calj737

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Re: 1976 550K Project
« Reply #41 on: December 08, 2014, 03:12:28 AM »
I should have this thing on the road by Saturday (after 22 years haha)...
Noticed you didn't say which Saturday-  ::)
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline mrfish2

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Re: 1976 550K Project
« Reply #42 on: December 08, 2014, 04:15:09 AM »
Haha good catch, but in fact I actually mean this Saturday! I'm not saying it'll be ready to take to a show, but it'll definitely be a daily driver for me.
1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.

Offline mrfish2

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Re: 1976 550K Project
« Reply #43 on: December 11, 2014, 01:47:37 PM »
She's done! (well...almost...) Got some new Dunlop K70 tires put on, brake caliper rebuilt, and finally finished bleeding the system today. New grips and mirrors curtosy of Dime City Cycles. Gave the tank a polish and wax yesterday and boy does it shine now, even with the faded paint.

Rode her for the first time today too, and man was it sweet. Then after about ten miles I came to a stop light and she sputterd and died, so I thought maybe the idle screw was too far out. Kicked her back to life, adjusted the idle screw, and went on my merry way. The very next stoplight I came to she decided to do the same thing again. Kicked her back a second time (with cars honking at me from behind) and proceeded to get home as fast as I could. I'm pretty sure the vacuum leak is back cause the idle kept hanging up, and when I got back I checked the headers to find that #4 was cool enough to touch (this being after a ~30 minute ride). Any suggestions?


The day I brought her home


Today


1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.

Offline streak09

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Re: 1976 550K Project
« Reply #44 on: December 11, 2014, 04:10:08 PM »
I'm getting some Dow Corning grease in the mail this week so i can finish up the brake rebuild

Is that just an overall lubricant? Or used for very specific applications?

Also, congrats on the maiden voyage! If you can touch a header after a 30 minute ride, then its not fireing at all. What do the plugs look like? You mentioned an overflowing carb, maybe it is now stuck closed? I think you are on the right track with vacuum leak as well.

Offline mrfish2

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Re: 1976 550K Project
« Reply #45 on: December 11, 2014, 04:17:27 PM »
The Dow Corning stuff is for the back of the brake pads where they come in contact with the caliper bodies. When the caliper heats up from being used this type of grease (pure silicone) won't run everywhere like a typical petroleum grease. There's a few threads around here that go into more details about it.

The plugs are brand new, but I've yet to pull them out. It was getting dark when I got home so the agenda for tomorrow is to figure out for sure if it's a vacuum leak or not, and pull the bowl off the #4 carb to see if anything is sticking. I adjusted the points and tappets a few weeks ago, and it shouldn't be the coils because #1 IS firing. But will a vacuum leak cause a specific cylinder not to fire?
1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.

Offline streak09

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Re: 1976 550K Project
« Reply #46 on: December 11, 2014, 06:34:15 PM »
In my experience a vacuum leak is usually associated with hanging revs. I wouldnt think it would cause a no fire condition, maybe in severe cases (like no manifold  ;)).

Offline mrfish2

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Re: 1976 550K Project
« Reply #47 on: December 11, 2014, 06:40:05 PM »
Maybe it's the other way around? As in not getting fuel or spark to that cylinder might cause it to sputter and die at idle? I posted this question in the Bikes thread so more people might see it.
1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.

Offline calj737

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Re: 1976 550K Project
« Reply #48 on: December 12, 2014, 04:26:09 AM »
More than likely you're not getting fuel to #4. But, double check the plug caps to the coil and spark plug are fully seated. Then, open the drain screw underneath the offending carb and catch the fuel that flows out. Any debris?

Start the bike, and use the handle of a screwdriver and rap on the carb body. This can help dislodge a stuck float or stuck "closed" float valve. It's not uncommon to agitate debris that's accumulated in the gas tank after years of sitting idle on maiden voyages. Is there an inline filter of have you fully cleaned and flushed the tank to verify no corrosion?

Pipe should be equally hot within 30-60 seconds of firing. Use a spray bottle of water directly onto the header to avoid scalding your hand, but test them for temps promptly. If they're hot, and you ride but the bike quits, pull over and test the pipes each. If a pipe continues to work, then not, probably a float issue in that carb (wrong height or debris as mentioned).

Eliminate these possibilities before moving on to igntion, and set your idle once, after hot and leave it be. And vacuum synch your carbs soon.
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline mrfish2

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Re: 1976 550K Project
« Reply #49 on: December 12, 2014, 09:57:23 AM »

It ended up being the float valve in the #4 carb, so now that pipe is just as hot as the rest. And no, I don't have a fuel filter on the lines. I cleaned and RedKoted the tank a few weeks back.

But after fixing the float valve and setting the height again I rode it for a few miles and it struggled getting up hills and misfired a lot. Like I would roll on the throttle and it would speed up, then die, then speed up again, and sometimes die a second time before finally speeding up. Definitely not the "flat spot" I've read about. I'm gonna go check the tappet clearances again to be sure, but it sound like it's a vacuum leak again.
1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.