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Installed Ring Gap
- CoreyClough
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Looking in my factory supplement manual for the '84->, it doesn't state the piston ring gap as installed in the cylinders. It does show it for the ZR550, which should be the same as a KZ550 I believe??? The top and second installed ring gap should be 0.15-0.30mm( .006-.011" ) With a Wear Limit of 0.6mm( 0.023" ). None for the oil rings obviously. Is there a "rule of thumb" to ring gap and bore size?
In another manual I have, it states no installed ring end gap for the '84->(A1-A3), but it states it gap for KZ550-F1, M1.
I'm getting set to gap the rings for the head I've surface-honed a month back, as the standard rings have finally come in.
Here's the spec's on the used pistons I have:
Piston Ring Groove Thickness Information ZR550/KZ550:
Top 1.21-1.23mm(0.047-0.048" ), Wear Limit 1.131mm(0.051" )
2nd 1.23-1.25mm( 0.048-0.049" ), Wear Limit 1.33mm(0.052" )
Oil 2.51-2.53mm( 0.098-0.099" ), Wear Limit 2.61mm( 0.1027" )
Actual Piston Groove ReadingsGPz550:
Top and 2nd 1.207mm( .0475" )
Oil 2.438mm( .095" )
The Piston Grooves seem to be within the service limit, but it's the ring gap I'm worried about. Not too big, and not too small. Anyone think the above listed gap should be OK? Right out of the box, the top and second ring installed gap measure within the above recommendations.
Pictures? You bet!!!
Rings in the bore about 1/2 way down. Can you see the "T" Stamp?
Tiny "T" for top, barely visible just to the left of the gap:
Ain't no way I'm missing the "T", so I've highlighted them all:
Not a trick question, but which one is the compression ring, and which one is the second ring? They are both are the same thickness of 1.168mm( 0.046" ).
Any input would be greatly apreciateded. Thank you.
'85 GPz550(ZX550-A2)
GPz550 Base Manual --> tinyurl.com/ze5b3qo
GPz550 Supplement Manual --> tinyurl.com/h34d2o6
GPz550.com --> www.nwsca.com/scripts/gpz_forum_2005/default.asp
First Race Win GPz550 --> tinyurl.com/o5y3ftp
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- BSKZ650
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If you are using stock rings with rehoned bores, then they are prob going to be on the larger side , wear in the cyls and material honed,
The ring you show on the top, is the top ring.
also dont forget to check the wear in the piston ring land area
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- CoreyClough
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As you can see, the ring land area is very good. These pictons have very low mileage on them, and look to be in excellent condition with very little wear.
'85 GPz550(ZX550-A2)
GPz550 Base Manual --> tinyurl.com/ze5b3qo
GPz550 Supplement Manual --> tinyurl.com/h34d2o6
GPz550.com --> www.nwsca.com/scripts/gpz_forum_2005/default.asp
First Race Win GPz550 --> tinyurl.com/o5y3ftp
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- bountyhunter
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This is a stock '84-> GPz550 engine, with standard bore pistons and rings.
Looking in my factory supplement manual for the '84->, it doesn't state the piston ring gap as installed in the cylinders. It does show it for the ZR550, which should be the same as a KZ550 I believe??? The top and second installed ring gap should be 0.15-0.30mm( .006-.011" ) With a Wear Limit of 0.6mm( 0.023" ). None for the oil rings obviously. Is there a "rule of thumb" to ring gap and bore size?
YES, and here it is:
ring end gap should be about .003" - .004" (nominal) PER INCH OF PISTON DIAMETER.
3" diameter piston: .009" - .012" (nominal)
my manual also says the service limit is about twice the nominal value.
1979 KZ-750 Twin
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- bountyhunter
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Not a trick question, but which one is the compression ring, and which one is the second ring? They are both are the same thickness of 1.168mm( 0.046" ).
The ring with no grooves is the top ring. The one with the grooved lip is second, lip goes downward.
1979 KZ-750 Twin
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- CoreyClough
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There aren't any cut-outs, or odd shape on either of the rings. Just what you see there. They are both the same thickness top to bottom, and inside to outside.
'85 GPz550(ZX550-A2)
GPz550 Base Manual --> tinyurl.com/ze5b3qo
GPz550 Supplement Manual --> tinyurl.com/h34d2o6
GPz550.com --> www.nwsca.com/scripts/gpz_forum_2005/default.asp
First Race Win GPz550 --> tinyurl.com/o5y3ftp
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- bountyhunter
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1979 KZ-750 Twin
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- CoreyClough
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www.riken.co.jp/e/piston/b/b_2.html
I do think you are right about the top ring being the one having the "special" edge. I don't have the rings that came off of these pistons, as that might help too.
Yes, interesting the piston ring groove, and the rings are exactly the same for the top and bottom, dimension-wise. I would think Kawasaki would state which ring goes on top, by maknig a 1 or a 2 next to the "T" stating the correct placement.
Thanks again for your replies.
NOTE*** Looking at the picture above, the darker ring, deemed the 2nd ring, has a bigger free gap than the one you stated is the top ring.
'85 GPz550(ZX550-A2)
GPz550 Base Manual --> tinyurl.com/ze5b3qo
GPz550 Supplement Manual --> tinyurl.com/h34d2o6
GPz550.com --> www.nwsca.com/scripts/gpz_forum_2005/default.asp
First Race Win GPz550 --> tinyurl.com/o5y3ftp
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- mark1122
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offten the second ring sometimes has a slight taper.
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- CoreyClough
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Someone has got to know for sure which ring goes on top, and which goes in the 2nd position.
'85 GPz550(ZX550-A2)
GPz550 Base Manual --> tinyurl.com/ze5b3qo
GPz550 Supplement Manual --> tinyurl.com/h34d2o6
GPz550.com --> www.nwsca.com/scripts/gpz_forum_2005/default.asp
First Race Win GPz550 --> tinyurl.com/o5y3ftp
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- timebomb33
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1973 z1 2-1974z1-a,2-1975z1-b dragbikes1015cc+1393cc, 1977kz1000,1978kz1000,1981kz1000j, 1997 zx-11, 2000 z12r,1428turbo nitrous pro-mod and a shit load of parts thats all for now leader sask.,CANADA
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- CoreyClough
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Like Chris Farley said on Tommy Boy,"If you want to get a good look at a T-Bone you could stick your head up the bull's a$$, or you could just take the butcher's word for it."
'85 GPz550(ZX550-A2)
GPz550 Base Manual --> tinyurl.com/ze5b3qo
GPz550 Supplement Manual --> tinyurl.com/h34d2o6
GPz550.com --> www.nwsca.com/scripts/gpz_forum_2005/default.asp
First Race Win GPz550 --> tinyurl.com/o5y3ftp
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