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Discussion Starter · #1 ·
Last fall I noticed the bike popping and not riding well 'til it warmed up, but didn't think much of it.



Over the winter I replaced the carb float bowl gaskets, and did a few other little things.



I just took it for its first ride of the year yesterday. It worked fine at first. Then I parked and let it rest for a few hours. When I rode it again, it wouldn't reach full power and felt very much like it felt last year when it wasn't warmed up (regardless of how warm I let it get).



I figured it was maybe the old gas, so I filled with fresh and rode it around for 20 minutes. It was pretty much the same. A few times it seemed to spark to life very briefly, but then quickly subside again.



It's not the stator/CDI I don't think. I had that problem once and put in an Ignitech. This cut-off isn't as quick. It's just a general bogginess and lack of power.



Maybe I need new spark plugs? I've ordered some and will put them in this weekend. I just figured I'd ask you guys as you know so much about these old bikes. Maybe this is a common occurrence and you can point me in the right direction.
 

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Last fall I noticed the bike popping and not riding well 'til it warmed up, but didn't think much of it.



Over the winter I replaced the carb float bowl gaskets, and did a few other little things.



I just took it for its first ride of the year yesterday. It worked fine at first. Then I parked and let it rest for a few hours. When I rode it again, it wouldn't reach full power and felt very much like it felt last year when it wasn't warmed up (regardless of how warm I let it get).



I figured it was maybe the old gas, so I filled with fresh and rode it around for 20 minutes. It was pretty much the same. A few times it seemed to spark to life very briefly, but then quickly subside again.



It's not the stator/CDI I don't think. I had that problem once and put in an Ignitech. This cut-off isn't as quick. It's just a general bogginess and lack of power.



Maybe I need new spark plugs? I've ordered some and will put them in this weekend. I just figured I'd ask you guys as you know so much about these old bikes. Maybe this is a common occurrence and you can point me in the right direction.
keep an eye on my thread,[just in case something rings true] ill post it in 10 minutes.gotta look to the mrs,and her cutting in.
 

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Discussion Starter · #4 ·
I'll have a look into the plug boots to see if I can buy some new/aftermarket ones. I do have an inline fuel filter on the bike. I was thinking maybe it was carb related as it ran fine for the first hour of the season, but then after having gas (old gas at that) sit in the carbs for a few hours it bogged down. My main issue now is that all of my fixes are "side of the street in Chicago" style fixes so I'm somewhat limited in what I can/can't do.



Check out the plug boots? Just saw that some people have had some brand new yet junk plugs. You got a clean fuel filter on that beast?
 

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"Winterized" bikes can suffer badly from stale fuel.It causes a patina to coat inner carb parts.Use some cheap Petrol treatment from a supermarket as per its instructions in a good few tanks of gas and you may be ok.If not it's a carb strip and service IMHO.

Also get a can of carb/brake cleaner and if you can get the float bowls off with the carbs on the bike(That gnarly inner screw is a beeatch so I have Allen screws in mine) you can spray up and into the Float needle valve holes to see if it will clear them.
 

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Discussion Starter · #7 ·
Added some seafoam to the gas this evening. Will run it for a while tomorrow to see if it helps. I can't find my plug socket so I've ordered another one. Will pull the plugs once it gets here to investigate further.



I've also ordered new caps just 'cause it's a 30 year old bike and it can't hurt.



This forum is great.



is more interested in how Bandit managed to have his wife cutting in while hes purusin' the forum!




All good advice...but sounds like obstructed fuel delivery. Have you pulled the plugs to see what color they are?
 

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Just a thought in passing. It COULD be the main fuse going south on ya. This has been known to cause "erratic" behavior.



After re-reading your post again, almost sounds like some crud moving around inside your carberators plugging up tiny little holes and passages and, as "passing through" bike runs good, till the next one comes down the line and does the same thing.



Do you have an inline filter installed?



Do you have your gas tank lined? If not, could be rusty particles from inside the gas tank plugging up the "straw" filter inside the tank.



Don't know if your bike has vacuum petcock. COULD be that also.
 

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Discussion Starter · #9 ·
I hadn't thought about the main fuse. Once I rule out plugs/caps I'll look into it. I do have an inline fuel filter.



Things got weirder today. I started it this morning after the seafoam treated gas sat in the carbs overnight. It is now idling REALLY high. I can't seem to get the idle to come down at all (I assume that's what the knobbed screw under the carbs is for? What direction does what on that thing? I'm not noticing any difference as it gets turned).



I also noticed a bit of gas under the bike this morning. I reckon its from the left-hand cylinder weep hole, so I assume that cylinder isn't firing...



Hopefully the plugs/caps/socket will be here tomorrow and I can replace all of those.



Just a thought in passing. It COULD be the main fuse going south on ya. This has been known to cause "erratic" behavior.



After re-reading your post again, almost sounds like some crud moving around inside your carberators plugging up tiny little holes and passages and, as "passing through" bike runs good, till the next one comes down the line and does the same thing.



Do you have an inline filter installed?



Do you have your gas tank lined? If not, could be rusty particles from inside the gas tank plugging up the "straw" filter inside the tank.



Don't know if your bike has vacuum petcock. COULD be that also.
 

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Going to show my lack of knowledge of the Ignitech here.

I A$$ume you use the standard coils with the Ignitech.



I would suspect coils.

The warmer they get the more it is likely to be unhappy.

Check them out with a multimeter. Check the voltage going to them also. My KZ had only about 10V through the main wiring harness getting to the coils. You might have acquired a questionable connection.

Once you have the plugs I would look at the spark then get it good and warm then retest.

You can also warm the coils up by using a hair dryer.



Of course if the Ignitech does not use the stock coils then ....
 

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if your bike has been left out all winter in the windy city....

im gonna guess you have a massive air leak.the rubbers on your boots etc,have gone hard,clips slack etc.

you have 6 possible joints that can leak air,check them well before you move on to other possible causes
 

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Discussion Starter · #12 ·
I figured I'd update this thread in case someone comes across it in their search results. It turns out that cleaning the carbs did the trick. Although I'd cleaned them over the winter (I kept the bike indoors), I think the first bit of gas that went through them gummed them up a bit. Blowing some carb cleaner through all of the needles and reassembling did the trick. The bike now seems to pick up a bit better than it ever did (although that might be in my head after becoming accustomed to a week or so of bogginess).



Now I need to source a fender to repair the front end, as somebody knocked my bike over with their car the other day...
 

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I would like to emphasize the plug boots. I came on here with problems, and the first thing I was told was to check the plug boots. I of course being the noob that I was (still am a noob, just not as bad of one) only looked around the outside of them, then did other things to make the problem better but not fix it.



I was able to make it run a lot better by closing the spark plug gap. Granted the plugs were gapped too wide, but it changed performance drastically (though it still wasn't where it should have been). So, check your gap, and actually take apart those boots and look at them. It isn't hard to rebuild them. The hardest thing to do is get the old crap out of them if they're stuck (they were with mine). Just stick a copper brass or aluminum rod in there if you're ok with going without the resistors (I recommend this, but it's mostly personal preference.)
 

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I would like to emphasize the plug boots. I came on here with problems, and the first thing I was told was to check the plug boots. I of course being the noob that I was (still am a noob, just not as bad of one) only looked around the outside of them, then did other things to make the problem better but not fix it.



I was able to make it run a lot better by closing the spark plug gap. Granted the plugs were gapped too wide, but it changed performance drastically (though it still wasn't where it should have been). So, check your gap, and actually take apart those boots and look at them. It isn't hard to rebuild them. The hardest thing to do is get the old crap out of them if they're stuck (they were with mine). Just stick a copper brass or aluminum rod in there if you're ok with going without the resistors (I recommend this, but it's mostly personal preference.)


I recommend using the plugs with built in resistors.

The reason being I understand these bikes ignitions can be damaged by a return ring from the spark.

I am not sure where I read it on the forum BUT for the couple of dollars why not use the resistor plugs. It does not hurt your spark and it might protect your ignition.

It is the ounce of prevention versus a pound of cure theory.

It is what I did.

Just my thoughts.
 

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I made that post without thinking it through fully. I use Iridium plugs with built in resistors. I would use straight Iridium if I could have found it, but now I'm just going to use the ones with built in resistors just to play it safe. It is all about personal preference though. I also run an ignitech so the return spark thing may be moot.
 

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I made that post without thinking it through fully. I use Iridium plugs with built in resistors. I would use straight Iridium if I could have found it, but now I'm just going to use the ones with built in resistors just to play it safe. It is all about personal preference though. I also run an ignitech so the return spark thing may be moot.


Agreed.

Personal preference. The Ignitech I suspect is immune to the return ring.

Did you notice a performance improvement with the Ignitech system install?
 
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