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compression problems?
- IowaKZ
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16 Aug 2008 16:46 #232386
by IowaKZ
1980 G1 Classic
Bettendorf, Iowa
compression problems? was created by IowaKZ
I have an issue with my 1980 KZ1000 G1. It just doesn't seem to have the power I think it should. it's kind of balky until it gets really warm. It shouldn't be an issue, except this:
when I put new plugs in, it's really peppy for a day or two, then it settles back down to kind of sluggish.
Plugs in 1, 3, & 4 are a little oily. plug 2 looks good.
I checked the compression cold today and here is what I got: I checked each one 2x.
1: 145 to 150
2: 140 to 145
3: 150 both times
4: 150 to 160
then I put some oil in #2 and rechecked it and it increased to 150 both times.
I have not checked the valve clearance yet, I wanted to check the compression first.
Are these compression values ok? Is #2 a concern? Are the oily plugs a sign of ring problems?
Sorry for all the questions. Oh yes, I am running the original EFI, so there is not really any adjustment, although I could change out my fuel filter and run some seafoam throught it i guess.
Any other thoughts?
thanks much.
when I put new plugs in, it's really peppy for a day or two, then it settles back down to kind of sluggish.
Plugs in 1, 3, & 4 are a little oily. plug 2 looks good.
I checked the compression cold today and here is what I got: I checked each one 2x.
1: 145 to 150
2: 140 to 145
3: 150 both times
4: 150 to 160
then I put some oil in #2 and rechecked it and it increased to 150 both times.
I have not checked the valve clearance yet, I wanted to check the compression first.
Are these compression values ok? Is #2 a concern? Are the oily plugs a sign of ring problems?
Sorry for all the questions. Oh yes, I am running the original EFI, so there is not really any adjustment, although I could change out my fuel filter and run some seafoam throught it i guess.
Any other thoughts?
thanks much.
1980 G1 Classic
Bettendorf, Iowa
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- bill_wilcox100
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16 Aug 2008 17:45 #232392
by bill_wilcox100
1977 KZ650-B1 (Stock)
Upgrades:
- Dyna S Electronic Ignition (DS2-2)
- Dyna 3 Ohm Coils (DC1-1)
- Coil Repowering Mod
- Progressive Springs Front & Rear
- Saddlemen Seat Cover
- New Metallic Red Re-Paint & Repro Badges.
Montreal, Canada
Replied by bill_wilcox100 on topic compression problems?
Your "Oily Plugs" symptom does not appear to follow the compression results.
The oily plugs can be caused by the intake valve leaking some oil into the fuel intake and coating your plugs.
However, intake valve #2 is probably OK.
Best of success.
The oily plugs can be caused by the intake valve leaking some oil into the fuel intake and coating your plugs.
However, intake valve #2 is probably OK.
Best of success.
1977 KZ650-B1 (Stock)
Upgrades:
- Dyna S Electronic Ignition (DS2-2)
- Dyna 3 Ohm Coils (DC1-1)
- Coil Repowering Mod
- Progressive Springs Front & Rear
- Saddlemen Seat Cover
- New Metallic Red Re-Paint & Repro Badges.
Montreal, Canada
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- IowaKZ
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16 Aug 2008 18:20 #232397
by IowaKZ
1980 G1 Classic
Bettendorf, Iowa
Replied by IowaKZ on topic compression problems?
Thanks Bill, I guess the next step is to check my valve clearances.
1980 G1 Classic
Bettendorf, Iowa
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- bill_wilcox100
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16 Aug 2008 20:01 - 16 Aug 2008 20:02 #232408
by bill_wilcox100
1977 KZ650-B1 (Stock)
Upgrades:
- Dyna S Electronic Ignition (DS2-2)
- Dyna 3 Ohm Coils (DC1-1)
- Coil Repowering Mod
- Progressive Springs Front & Rear
- Saddlemen Seat Cover
- New Metallic Red Re-Paint & Repro Badges.
Montreal, Canada
Replied by bill_wilcox100 on topic compression problems?
At this point I doubt it's valve clearance. That would affect compression but not oil fouling.
More likely need new seals on the valve stems. If not then new valves. If not then new valve guides. IMHO.
Best of success.
More likely need new seals on the valve stems. If not then new valves. If not then new valve guides. IMHO.
Best of success.
1977 KZ650-B1 (Stock)
Upgrades:
- Dyna S Electronic Ignition (DS2-2)
- Dyna 3 Ohm Coils (DC1-1)
- Coil Repowering Mod
- Progressive Springs Front & Rear
- Saddlemen Seat Cover
- New Metallic Red Re-Paint & Repro Badges.
Montreal, Canada
Last edit: 16 Aug 2008 20:02 by bill_wilcox100.
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- IowaKZ
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17 Aug 2008 18:34 #232560
by IowaKZ
1980 G1 Classic
Bettendorf, Iowa
Replied by IowaKZ on topic compression problems?
Oh, didn't realize that might be an issue. Looks like I'm taking the head off this year. thanks for the help.
1980 G1 Classic
Bettendorf, Iowa
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- MFolks
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17 Aug 2008 18:40 #232563
by MFolks
1982 GPZ1100 B2
General Dynamics/Convair 1983-1993
GLCM BGM-109 Tomahawk, AGM-129A Advanced Cruise Missile (ACM)
Replied by MFolks on topic compression problems?
The valve guides could be worn,and the valve stem seals are probably dry and cracked all leaking into the cylinder(s).
What mileage do you have? are you the original owner?
What mileage do you have? are you the original owner?
1982 GPZ1100 B2
General Dynamics/Convair 1983-1993
GLCM BGM-109 Tomahawk, AGM-129A Advanced Cruise Missile (ACM)
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- IowaKZ
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18 Aug 2008 06:28 #232616
by IowaKZ
1980 G1 Classic
Bettendorf, Iowa
Replied by IowaKZ on topic compression problems?
No, I'm the 2nd or 3rd (2nd for sure). Miles: a little over 31k. I've had the bike since 2004 and I bought it with about 27k.
I had planned on doing a clearance check this summer and I already have a valve cover gasket. Looks like I need to take off the head too.
I had planned on doing a clearance check this summer and I already have a valve cover gasket. Looks like I need to take off the head too.
1980 G1 Classic
Bettendorf, Iowa
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- bountyhunter
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18 Aug 2008 12:14 #232688
by bountyhunter
1979 KZ-750 Twin
Replied by bountyhunter on topic compression problems?
IowaKZ wrote:
Has the head ever been off? If those are the original valve seals, they are probably hosed. They let oil run down the valve and into the cylinder and foul the plugs badly.No, I'm the 2nd or 3rd (2nd for sure). Miles: a little over 31k. I've had the bike since 2004 and I bought it with about 27k.
1979 KZ-750 Twin
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- IowaKZ
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18 Aug 2008 14:18 #232732
by IowaKZ
1980 G1 Classic
Bettendorf, Iowa
Replied by IowaKZ on topic compression problems?
I have not had the head off. Can't speak for the PO. I have to assume that the head has never been off.
this should be exciting. I've never taken one of these apart before. Now I have to find the time before it gets too cold out.
Maybe I can spring for a heater for my garage?
this should be exciting. I've never taken one of these apart before. Now I have to find the time before it gets too cold out.
Maybe I can spring for a heater for my garage?
1980 G1 Classic
Bettendorf, Iowa
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