Author Topic: 1975 CB550K1 550 Four  (Read 16787 times)

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Offline CJK

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Re: 1975 CB550K1 550 Four
« Reply #75 on: July 17, 2015, 01:59:50 PM »
...oh snap. I thought they were supposed to go that way because that's how they looked when they came off the bike!


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Offline CJK

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Re: 1975 CB550K1 550 Four
« Reply #76 on: August 12, 2015, 10:38:15 AM »
I flipped the float needles so that they are in the carbs correctly and actually work :)

I adjusted the float height and nowwww I understand why everyone says to adjust them with the carbs sideways because you don't want the spring depressed.

After adjusting the float height, I installed the carbs as well as air filter. Then checked the points gap and set static timing.

...and voila! I kicked it over a few times and it actually started. I was really shocked it works.

It appears cylinder 1,2, and 4 are firing. The header pipe for #3 didn't feel warm.



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Offline CJK

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Re: 1975 CB550K1 550 Four
« Reply #77 on: August 20, 2015, 06:14:37 PM »
The idle still isn't quite right. Cylinder 3 is firing. So I decided to take the plugs out and see what's going on.

All the air screws are at 1.5 turns out. It seems like #3 isn't getting any fuel so carbs are coming off to clean out the pilot jet again.



Can someone offer some suggestions to help out?


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Offline calj737

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Re: 1975 CB550K1 550 Four
« Reply #78 on: August 20, 2015, 07:16:11 PM »
First thing to do is to perform a Clear Tube check of the fuel level. This is a major indicator of what's happening internally to your carbs. You can even fire the bike and watch the fuel level while revving the motor.

Post pictures of that
'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 CJK

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Re: 1975 CB550K1 550 Four
« Reply #79 on: August 20, 2015, 07:30:33 PM »
Roger that, calj737. I will try to get  that done now. I'll lodge the tubing into the drain screw hole


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Offline CJK

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Re: 1975 CB550K1 550 Four
« Reply #80 on: August 20, 2015, 08:00:58 PM »
There is clear tube method for carbs #3 and #4. The bike was not running at the time. I think I'll need an assistant to be able to hold the tube in, start the bike and take a picture next time.

...although next time, I probably won't spill nearly as much gas so it won't be as messy.






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Offline streak09

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Re: 1975 CB550K1 550 Four
« Reply #81 on: August 21, 2015, 03:25:29 AM »
No need to have the bike running. Just make sure it is standing up straight, not on the side stand.

Offline CJK

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Re: 1975 CB550K1 550 Four
« Reply #82 on: September 27, 2015, 03:17:41 PM »
Been working on it on and off. I verified with the clear tube method that the floats are set correctly and that fuel is in the bowl. After that, I removed carbs and cleaned passageways one more time as well as swapped slow jets between Cylinder 3&4.

While idling, the bike is still having trouble running on all four cylinders. After running it yesterday, I checked the pipes and all 4 were very hot (I checked by licking them).

I picked up a HF Compression Test kit to do a quick compression test. This kit has a 1/2" x 20" hose length, so I know my readings are lowered do to that. I did 3 5-6 revolution readings on each cylinder with open choke and WOT. All cylinders were showed about ~53-58 PSI, which puts them in the +- 10% range.