02 zx-6r cold morning starting issues (possibly spark?)

ucmgrad

Well-known member
Hey Everyone,

Looks like I need the BARF collective wisdom and I'm seeking your advice. After I re-shimmed the valve (bike has 103k miles) I noticed the bike is starting to have cold-morning starting issues. Bike doesn't want to fire or when it does it sounds like it's missing. Fueling was never an issue but I have a strong suspicion it's a spark issue, I gapped the spark plugs on the smaller end of the spectrum. But I feel it could be this issue:

When I reinstalled the coil packs, a couple of them didn't have that satisfactory "clicking feeling" when the coil pack grabs onto the metal threaded terminal. Once the bike warms up completely it runs fine and even during the middle of the day when I get off of work it doesn't have this issue and it starts without issue. Just to get it out of the way, is there anyway to repair the little metal connecting part of the coil pack that grips the spark plug since it's loose?

Thanks!:cool

P.S. I circuled the part of this generic coil pack picture of the metal connecting part that doesn't grip the spark plug tight anymore is that makes sense.

1SvF5Mul.jpg
 

Maddevill

KNGKAW
Did you remove the threaded cap on the top of the new spark plugs ? If not, the coil is just sitting loosely on those caps.

Mad
 

ucmgrad

Well-known member
Maddevil - That's the first thing I did because I've made that mistake before. I ensured it was the "threaded" end exposed on the spark plug. A couple of the coil packs stick "click" but others don't. To isolate the program I even pulled off the coil packs, pulled off the rubber isolation boots just to see if the spark plug would "click" into the coil packs on a work bench and I remember one or two of them not giving that satisfactory "click".
 

Tom G

"The Deer Hunter"
That connection would not be a problem if your ignition coil works properly. In the 20 year life of my 6-cyl Nissan I had to replace about 5 of the 6 ignition coils (similar design). The electronic had intermittent faults. In your case I would think if the mix is too lean in order to start the engine. I had my R1200GS stall a few times riding out of my apartment property if the outside temperature was just right.
 

Busy Little Shop

Man behaving bikely...
Spark problems would show consistently when the engine is laboring under a load...

Hard to start problems is mostly a problem of not enough fuel is being sucked into the combustion chamber...

Generic things to check for that would effect cold starting are:

1) enriching cable adjustment if you have one... too loose or too tight effects range...

2) unobstructed idle air tubes... pinched rubber tubes from the air box restrict
idle air... the result is a lean mixture that doesn't support 100% combustion...

3) throttle body butterflies are 100% closed... any air that bleeds past the
butterflies kills vacuum needed to draw in the correct rate of fuel... the result
is a lean mixture that doesn't support combustion...
 
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ucmgrad

Well-known member
TOM G: This issue occurred after I re-shimmed the valves, installed new plugs (gapped them to the tightest of the spectrum) and noticed how loose the metal connector was on two of the coil packs. I'm thinking of re-gapping the plugs to the middle of the spectrum.

BLS:
1. I've never adjusted the chock cable as it's never been an issue before

2. This weekend I do plan on checking the vacuum lines because that very well be an issue, I might have pinched a tube when reinstalling the airbox.

3. It still idles but it fluctuates slightly so I might increase the idle slightly to see if this helps with cold starting issues, thank you!
 

ucmgrad

Well-known member
Small Update:
The ninja didn't start this morning (go figure). Well it starts but like I previously stated, it sounds like it's missing and then cuts out/shuts off intermediately and then won't start anymore. You can smell gas coming from the muffler so I know it's getting both air/fuel so I'm figuring it has to be spark. Would too small gapping on the spark plugs cause cold starting issues? What does everyone gap their plugs to? The smaller end, middle or larger end the gap range for their machine?
Also is there any suggesting to tighten the grip of the coil thread on the coil pack to improve connection?
 

GPzPop

Ask me about my B-1-D
I have a set of the (4) stick coils for this model bike (zx600j) from when I was chasing a performance issue with mine.

turns out my stumble / miss was from a lost tiny o ring in the carbies

ultimately I solved the issue and my zzr is running great, up to 175K miles and counting

if you want to try out swapping the stick coils to see if there is any improvement, pm me
 
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Busy Little Shop

Man behaving bikely...
To test your assumption that it has to be spark wait for darkness and insert a
spare plug into the pack and ground the plug to the engine and hit start... you
should see a nice blue arc jump the gap...
 

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ucmgrad

Well-known member
GPzPop - Thanks for the offer, i'm going to check the gaps and spark plug connections this morning and follow up with you. If nothing improves I'll let you know and we can set something up. I appreciate the offer! :cool

BSL - I'm going to be checking spark as well against the frame to make sure everything is good and will be sure to follow up.

I'm hoping it's not a carb issue, worst comes to worst I could always rebuild the carbs. I've never taken these apart as I've always ran the bike and it's never sat for more than a couple months. I do have experience taking apart j-series carbs apart when I got my buddies 01 back on the road though
 

afm199

Well-known member
As the nights get colder, this is the time of year when battery issues begin to show themselves. A battery that has worked perfectly on hot days will not work well on cold days if it is getting old.

PS: If you coil pack is not clicking into place, then there's a problem. The pack has clips that need the threaded post on top of the plug to snap onto. After a few applications they will wear loose, and no, they don't work properly if not snapped on. At a minimum, pull all four plugs and swap holes, that will change the orientation of the threads. Also remember that you may have to push down HARD to get them to seat. If they aren't seating, go no further, that's the problem.
 
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ucmgrad

Well-known member
Small Update:

As I was pulling the airbox off I noticed that one of the vacuum lines (there's two rubber "T's" in between the carbs between the 1/2 and 3/4 cylinders) that was loose which I think is causing a vacuum leak which is why it might not be holding idle and sound like its missing. As a temporary fix I zip tied (I know) to tighten up the connection and it seems to start even better and hold idle better. As an added measure I'm going to order those rubber t's and replace them because I feel that maybe because of that slight vacuum leak it could not be pulling the slides as it should causing it to miss and not run right.

afm199: thanks for the suggestion, it's an oreilly auto battery that's less than a year old so I'll take it in sometime this weekend or this week to get it tested to see what the condition is.
 

ST Guy

Well-known member
An auto battery? How'd you fit that into your bike?

And if you take the battery to O'Reilley's for a check, don't trust those electronic load testers they have. They are notorious for saying a bad battery is good. Find a place with a tester that applies a real load to the battery. It's the only way.

Voltage you can test yourself.
 

ucmgrad

Well-known member
ST Guy: Sorry, I should clarify that the battery is a motorcycle one, but it's oreilly's in house brand (can't remember the name) but it is an oem-spec one. :cool
 

bobl

Well-known member
To help eliminate a battery problem, jump it off of your car (car not running). If it leaps to life, you probably have a marginal battery.
 

ST Guy

Well-known member
To help eliminate a battery problem, jump it off of your car (car not running). If it leaps to life, you probably have a marginal battery.

True. But don't have the engine on the jumper vehicle running.
 

ucmgrad

Well-known member
GPzPop - Unfortunately I haven't checked up to see if I'm still having the starting issue. : | We're getting major construction done on the house so I'm commuting by truck and dropping off my dog at my Grandma's house so he's not in the way of the workers :laughing

I have time this weekend and I'm also going to clean the connectors and test the fuel pump to see if that might be an issue. Given you have a similar bike, do these J-series ninja have fueling issues? I'm still running the original pump with 100k plus miles.
 

GPzPop

Ask me about my B-1-D
hi Luis,
mine is just past 175k (!) i did have to replace fuel pump. symptoms of that issue are that the bike would run about 1/2 mile then quit
 

ucmgrad

Well-known member
I was looking at replacement pumps on ebaymotors and it looks like replacements can be had for about $40, might just get one since it's soo cheap.
 
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