Topic: 78 CB 550K motor rebuild

[AlekStooge]

Got the assortment. I found a 5 pack for $7.25 on Ebay. This was a better value.

I'm debating on whether to dig into the top end to see what it going on.

[AlekStooge]

I took off the valve cover last night.


I was concerned about the pucks being so loose when I was installing them. They are a lot more snug.

I don't have compression gauges or a compressor to do a leak down. I either bent a valve due to inexperience during my cam degree or I over gapped the piston rings, yeah I was unsure of that when I was filing them.

Here are the plugs 1-4, bike was upright when running






Anyone care to chime in?

I also looked at my carbs. Cal mentioned to take the 45 pilots out. I must have forgotten to do that. I don't have replacement 42s, just the original which are pretty gnarly. Only one of them is drilled out by the PO. 108 on the mains.

[AlekStooge]

I got a Motion Pro compression guage. I also was looking at a Bikemaster because of more fittings and the schrader is at the plug end. I know consistency across cylinders matters more than accuracy but still I read having the schrader at the plug is better because of less volume. Correct? Read the engine FAQ on this as well.

Any here are the numbers with 59mm Wisecos 10:1

1-195 psi
2-194 psi
3-196 psi
4-195 psi

This is kicking the bike about 20 odd times for each cyclinder. These numbers are the highest I got them to go. I am concerned that it is oil sealing the rings because there is so much in there. Is that possible?

[AlekStooge]

Been a while since I worked on this or more acurately updated. I rebuilt the carbs and got them back on. I was going through my checks and noticed the exhaust valves were sitting high. I addressed this before but it bothered me.

I am degreeing the cam again. My center line numbers came up 95 intake and 88 exhaust. I am suprised it is that far off the card. I know it's whether they match that's important. I don't know which adjustment I should do? Logic would tell me, increase the exhaust.