Topic: CB 550 piston rings - which one goes top

[Fritz]

Hi!

I've ebayed a used cylinder block for my 550 lately that I want to have overbored 0.25mm

Today the repro piston kit arrived.
There are two kinds of piston rings. One with a beveled outer edge and one without.
I guess the beveled one goes on top of the other, right?

[bryanj]

The one with the chrome(grey) outer is the top ring, all numbers face upwards

[MRieck]

This thread should go in the FAQ section as the pic is very good and the answer to the point

[Fritz]

Ah, thanks a lot!

I didn't notice the chrome finish on the outer edge of the top ring. Should have read this thread carefully:
http://forums.sohc4.net/index.php?topic=60840.0

One last question: The manual says that the gaps should be 120° apart with no gap being in line with the piston pin or 90° off the pin axis. So would this pattern be right?

[bryanj]

Put the oil scraper expander in first, then the lower rail with the gap at about 90 Deg to the gap of the expander, then the top rail with the gap opposite the lower rail gap, 2nd ring at 120 from gap of oil expander, top ring 120 again.

Not in Honda book but from Hepolite(Big UK piston producer) many years ago

NB I should have said all MARKINGS face upwards as standards dont have numbers

[MRieck]

Put the oil scraper expander in first, then the lower rail with the gap at about 90 Deg to the gap of the expander, then the top rail with the gap opposite the lower rail gap, 2nd ring at 120 from gap of oil expander, top ring 120 again.

Not in Honda book but from Hepolite(Big UK piston producer) many years ago

NB I should have said all MARKINGS face upwards as standards dont have numbers

You've done this sort of stuff before?? 

[bryanj]

Just occasionaly since i got my OND in 1975 Mike!!!