Author Topic: Cb550 rebuild: in need of some serious advice  (Read 1277 times)

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Offline 700504

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Cb550 rebuild: in need of some serious advice
« on: June 22, 2016, 10:58:17 PM »
Currently working on rebuilding a 1978 cb550k for a friend. I've done motor work on several 750's and a 650 in the past and haven't come across the same issue as I'm having now. To make it short: I got to where I was honing the cylinders and notice the scores you can see in the attached pic. Catch a fingernail on it but if you press you finger really hard on the wall and rub; you can feel I very very slight dimple in one spot. What are my options? I'm feeling leery about this cylinder right now.
1978 cb750k
1977 cb750f2
1974 cb750k
1973 cb750k
1981 cb650 (rip)
1969 ct90

Offline strynboen

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Re: Cb550 rebuild: in need of some serious advice
« Reply #1 on: June 23, 2016, 02:29:41 AM »
find a used sleeve heat up cylendetbank and press it inn...think it vil rattel a lot ..use that one..the piston rings have be rusted in..and broken Loose..leave a korodet ring in the cast iron
i kan not speak english/but trying!!
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Offline calj737

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Re: Cb550 rebuild: in need of some serious advice
« Reply #2 on: June 23, 2016, 03:55:03 AM »
Replace or over-bore. You might try a rigid hone out of curiosity if availability and costs are impediments.
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

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Offline 700504

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Re: Cb550 rebuild: in need of some serious advice
« Reply #3 on: June 23, 2016, 08:18:30 AM »
Thanks for the advice guys, we're trying to find out all the options
1978 cb750k
1977 cb750f2
1974 cb750k
1973 cb750k
1981 cb650 (rip)
1969 ct90

Offline 700504

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Re: Cb550 rebuild: in need of some serious advice
« Reply #4 on: June 23, 2016, 08:37:15 AM »
I'll post it to parts wanted as well, but does anyone out there have just one standard bore sleeve for sale? Or should I get a whole othet set of jugs and make one out of two?
1978 cb750k
1977 cb750f2
1974 cb750k
1973 cb750k
1981 cb650 (rip)
1969 ct90

Offline 700504

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Re: Cb550 rebuild: in need of some serious advice
« Reply #5 on: June 23, 2016, 09:50:35 AM »
Just posted it to parts wanted for either a whole set or single sleeve, even if we have to go with a whole set, it'll be cheaper than a re-bore (since we've already purchased the rings and gasket kit).
1978 cb750k
1977 cb750f2
1974 cb750k
1973 cb750k
1981 cb650 (rip)
1969 ct90

Offline strynboen

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Re: Cb550 rebuild: in need of some serious advice
« Reply #6 on: June 23, 2016, 12:58:57 PM »
im in Europa so cant help.

..but i have used" a. used".(.2# used???..dont get that English)..... sleever and piston on my 400 four..and it vork just as fine as it vas new..so you are fine vith a used sleeve in spec kondision..but if you can..get the piston and rings vho run in the same part..then it vill be ekstra fine..a light ball /Flex hone if you use nev rings..
« Last Edit: June 23, 2016, 01:00:49 PM by strynboen »
i kan not speak english/but trying!!
http://forums.sohc4.net/index.php?topic=60973.0
http://forums.sohc4.net/index.php?topic=144758.0
i hate all this v-w.... vords

Offline 700504

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Re: Cb550 rebuild: in need of some serious advice
« Reply #7 on: June 23, 2016, 01:02:37 PM »
Thank you very much. Currently talking to someone on here with a set of cylinders. Hopefully they all check out fine. If not I'll be forced to replace the one sleeve. Already have new rings, already cleaned the pistons. Started honing then i found the pitting.
1978 cb750k
1977 cb750f2
1974 cb750k
1973 cb750k
1981 cb650 (rip)
1969 ct90