I have an 82 GS850G. I had low compression in #3, 90 PSI, so I took cylinder head off and while I was at it I might as well do the rings. I bought Genuine Suzuki Parts standard rings. The cylinders were all within specs, maybe a thousands off. Rings measured inside cylinder and had at least a .004 thousandths gap. Ring slots placed properly. I put on all new Vesrah gaskets. Lapped in the valve and after a gasoline test, no leaks. Now I never had great compression, never over 140 PSI and I have owned this bike for almost 8 years. My compression, hot, was 132. 132.128.139 respectively. Any suggestions why my compression is so low or did I leave any steps out? Book says 129-171 PSI is compression range.
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rings and valve lapping, still low compression???
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rings and valve lapping, still low compression???
HI AGAIN,
I have an 82 GS850G. I had low compression in #3, 90 PSI, so I took cylinder head off and while I was at it I might as well do the rings. I bought Genuine Suzuki Parts standard rings. The cylinders were all within specs, maybe a thousands off. Rings measured inside cylinder and had at least a .004 thousandths gap. Ring slots placed properly. I put on all new Vesrah gaskets. Lapped in the valve and after a gasoline test, no leaks. Now I never had great compression, never over 140 PSI and I have owned this bike for almost 8 years. My compression, hot, was 132. 132.128.139 respectively. Any suggestions why my compression is so low or did I leave any steps out? Book says 129-171 PSI is compression range.Tags: None
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Valves adjusted properly? Valve timing off?1984 GS1100GK newest addition to the heard
80 GS 1000gt- most favorite ride love this bike
1978 GS1000E- Known as "RoadKill" , Finished :D
83 gs750ed- first new purchase
85 EX500- vintage track weapon
1958Ducati 98 Tourismo
“Remember When in doubt use full throttle, It may not improve the situation ,but it will end the suspense ,
If it isn't going to make it faster or safer it isn't worth doing
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Forum LongTimerGSResource Superstar
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What type of hone and what grit was used to deglaze the cylinders? What processes did you use to break in the rings? Baby the engine or run it hard, or medium?Ed
To measure is to know.
Mikuni O-ring Kits For Sale...https://www.thegsresources.com/_foru...ts#post1703182
Top Newbie Mistakes thread...http://www.thegsresources.com/_forum...d.php?t=171846
Carb rebuild tutorial...https://gsarchive.bwringer.com/mtsac...d_Tutorial.pdf
KZ750E Rebuild Thread...http://www.thegsresources.com/_forum...0-Resurrection
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I used a friends honing triple stone , I don't know the grit. I'll check with I'm. As far as valve adjustment I have adjusted the valves three different times. I have them opened to .004 on the intake and about .003 on the exhaust to let more air in and that is the present reading. Timing is right on. The bike runs really good, I was just concerned about the low compression. I haven't broken in the rings or valves, all I have done is ride the bike around the neighborhood a couple of times. Should I give it a couple hundred miles and do a compression check then?
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Sounds like you're still running in. Those numbers are ok - and they're pretty even.
Plus are you sure your compression tester reads accurately. Mine reads low consistently.79 GS1000S
79 GS1000S (another one)
80 GSX750
80 GS550
80 CB650 cafe racer
75 PC50 - the one with OHV and pedals...
75 TS100 - being ridden (suicidally) by my father
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Originally posted by hampshirehog View PostPlus are you sure your compression tester reads accurately. Mine reads low consistently.https://drive.google.com/open?id=0B9zH8w8Civs8ejBJWjdvYi1LNTg&resourcekey=0-hlJp0Yc4K_VN9g7Jyy4KQg&authuser=fussbucket_1%40msn.com&usp=drive_fs
1983 GS750ED-Horsetraded for the Ironhead
1981 HD XLH
Drew's 850 L Restoration
Drew's 83 750E Project
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Originally posted by hampshirehog View PostSounds like you're still running in. Those numbers are ok - and they're pretty even.
Plus are you sure your compression tester reads accurately. Mine reads low consistently.http://img633.imageshack.us/img633/811/douMvs.jpg
1980 GS1000GT (Daily rider with a 1983 1100G engine)
1998 Honda ST1100 (Daily long distance rider)
1982 GS850GLZ (Daily rider when the weather is crap)
Darn, with so many daily riders it's hard to decide which one to jump on next.;)
JTGS850GL aka Julius
GS Resource Greetings
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Forum LongTimerGSResource Superstar
Past Site Supporter
Super Site Supporter- Mar 2006
- 35640
- Torrance, CA
Those three blade hones aren't the best for deglazing. The dingo ball type is better, in 240 grit.
I'd give that bike of yours the ol Italian tune up (ride the crap out of it). Last thing you want to do is baby it.Ed
To measure is to know.
Mikuni O-ring Kits For Sale...https://www.thegsresources.com/_foru...ts#post1703182
Top Newbie Mistakes thread...http://www.thegsresources.com/_forum...d.php?t=171846
Carb rebuild tutorial...https://gsarchive.bwringer.com/mtsac...d_Tutorial.pdf
KZ750E Rebuild Thread...http://www.thegsresources.com/_forum...0-Resurrection
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jdvorchak
Originally posted by Nessism View Post
I'd give that bike of yours the ol Italian tune up (ride the crap out of it). Last thing you want to do is baby it.
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