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Author Topic: Plugs, wet, sooty and misses  (Read 1442 times)

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Offline Hush

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Plugs, wet, sooty and misses
« on: October 24, 2008, 09:33:31 PM »
OK took the bike for a wee jaunt today (79 650 ) and it ran really really badly, I knew pretty soon it was only running on 3 and had to rev it at intersections to keep it alive.
Got home pulled plugs, #1 sooty black and fouled #2 wet/oily #3 sooty black and fouled # 4 ditto.
Cleaned plugs, swapped them around and bike starts up nicely again.
Question, why is #2 fouling?
Not having a compression tester is there any other way to test to see if #2 has blow past happening via say worn rings?
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I think the thing I most like about motorcycling is the speed at which my brain must process information at to avoid the numb skulls who are eating pies, playing the ukulele, applying make-up etc in the comfort of their airconditioned armchairs as they make random attempts to kill me!!!!!!!

Offline mrbreeze

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Re: Plugs, wet, sooty and misses
« Reply #1 on: October 25, 2008, 12:27:45 AM »
Are you sure its oil and not fuel?
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Offline Tower

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Re: Plugs, wet, sooty and misses
« Reply #2 on: October 25, 2008, 12:36:11 AM »
Perhaps first, put the carbs on a sync tool and see if any of them have suddenly gone out of sync?

Has the weather suddenly warmed up?  If so, that would suggest an overly rich carb setup.  Try 1/4 turn idle screws to the lean side.

Until you zero-in on the problem, coils/spark/timing can't be ruled out either.

« Last Edit: October 25, 2008, 12:39:49 AM by Tower »
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Offline Hush

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Re: Plugs, wet, sooty and misses
« Reply #3 on: October 25, 2008, 01:06:57 AM »
Hey Breezy, yeah been thinking it might be that too, carbs have just been synched by an expert (someone else of course) and this problem has just occured.
The big problem is that I haven't had the chance to get a lot of riding time in and much of this could be the bike complaining about doing too much idling and stop start work.
I was reading on another thread about swapping the plug leads over to test if the coils are the problem.
Can we do this on the 650's? that would be great I could take her for a scream on the back roads and see if the same plug fouled up. :)
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I think the thing I most like about motorcycling is the speed at which my brain must process information at to avoid the numb skulls who are eating pies, playing the ukulele, applying make-up etc in the comfort of their airconditioned armchairs as they make random attempts to kill me!!!!!!!

Offline mrbreeze

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Re: Plugs, wet, sooty and misses
« Reply #4 on: October 25, 2008, 01:38:01 AM »
I don't have a 650 so I don't really know the specifics of those carbs.As far as swapping plug wires....yeah....you can switch 2&3 or 1&4.
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Offline speedy gonzalais

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Re: Plugs, wet, sooty and misses
« Reply #5 on: October 25, 2008, 03:06:35 AM »
Im guessing you have mechanical carbs with the pilot screw at the bottom, for the european Z models its 1 1/2 turns out, us Z 1 5/8 turns and the 650A ans CA models 2 1/8 turns.
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Offline martino1972

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Re: Plugs, wet, sooty and misses
« Reply #6 on: October 25, 2008, 08:12:53 AM »
just the starting,stop,idling around might have done it to em....
maybe just put a new set of plugs in and do some good riding,meaning let her scream a few times on your trip,remember ,these bikes are the happiest when above 5000rpm....

see it could be that she is using oil abit,past the valve seals or rings,and in normal driving that will just burn out clean,but with alot of idling etc. the oil dont burn away,thus fouling the plugs....

mine did it too,cause it was sitting so long,but after a week of good riding it stopped burning oil al together...

just work that baby abit,she will reward ya....


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Offline Hush

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Re: Plugs, wet, sooty and misses
« Reply #7 on: October 25, 2008, 08:48:17 AM »
What? I don't have to weld anything to it???? ;D
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I think the thing I most like about motorcycling is the speed at which my brain must process information at to avoid the numb skulls who are eating pies, playing the ukulele, applying make-up etc in the comfort of their airconditioned armchairs as they make random attempts to kill me!!!!!!!

Offline martino1972

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Re: Plugs, wet, sooty and misses
« Reply #8 on: October 25, 2008, 08:49:13 AM »
Quote from: Hush on October 25, 2008, 08:48:17 AM
What? I don't have to weld anything to it???? ;D

not yet,oh,wait....yes,you do,your side stand!!!!!!!!!!!!!!
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Marti, I want you to know, I like you an awful lot, but guys have said far less and left wearing their drinks on their shirts.
http://forums.sohc4.net/index.php?topic=36933.0  (my bobber)

KingCustomCycles.com

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Re: Plugs, wet, sooty and misses
« Reply #9 on: October 25, 2008, 09:25:35 AM »
Quote from: Tower on October 25, 2008, 12:36:11 AM
Perhaps first, put the carbs on a sync tool and see if any of them have suddenly gone out of sync?

Has the weather suddenly warmed up?  If so, that would suggest an overly rich carb setup.  Try 1/4 turn idle screws to the lean side.

Until you zero-in on the problem, coils/spark/timing can't be ruled out either.



It is my humble opinion that a sync tool is usless until the carbs are ballpark close.  This is like starting someone on physivcal therapy on the way to the ER.  You had always hoped you would be rich someday, that day is today.
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KingCustomCycles.com

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Re: Plugs, wet, sooty and misses
« Reply #10 on: October 25, 2008, 09:27:11 AM »
Quote from: Hush on October 25, 2008, 08:48:17 AM
What? I don't have to weld anything to it???? ;D
Yes, just not today  ;D
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