Author Topic: Okay now im ready to throw this bike off the nearest cliff....help!  (Read 2633 times)

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Offline 78_SaltLick

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So, i had a problem start about 2 weeks ago one morning i get up and my bike is hard to start, once its started it runs like crap. Different cylandirs cutting out, wont idle on its own. Ive done every dam thing i can to figure this out. This is what ive done, anything missing?

replaced plugs
checked and regapped points
reseated plug wires
pulled tank and cleaned it out, twice now,  no rust left
pulled petcock and disassembled, completely cleaned it out
new fuel lines and fuel filters, new fuel
pulled carbs and blew out slow jets, main jets (in the process i broke off a slow jet in the carb, finally got the threads out, installed new slow jet)
reinstalled carbs (what a pain in the ass)
cleaned out float bowls multiple times

put the carbs back on last night, after many hours of sweating and cursing in the garage to get the carbs on, I start it up and wow! its running great. 5 minutes of riding it around the block and same dam thing. starts to slowly run like crap. Stop and let it idle, idle is inconsistant revs up and down on its own, bike is running better but still cuts out spits and sputters and just lacks all its guts still. Now its picked up a new sound, some sort of sucking noise occurs once in a while, probably something i did or missed while re-installing the carbs. pull up to the house and check pipe temps...now #1 is warm but not hot, others are burning hot. This happened before, #1 and #2 pipe are sometimes hot, sometimes just warm. What the hell is going on? i think ive ruled out a fuel problem. Man ive spent alot of hrs so far trying to figure this out, i know some work is necessary to keep these things running, but im about ready to take it down to the shop and give up on this one, im missing all the good riding time here! Anything im missin?




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don76

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #1 on: July 23, 2006, 06:34:50 AM »
When you cleaned the carb float bowls, did you take off the floats and make sure the needles were cleaned, so gas could get into the bowls?  The other question I would look into, especially if you are getting a sucking noise, is what shape are your rubber connectioens between the airbox and carbs and carbs and engine?  I've had problems with both, and the engine has run horrible in each case.  If the needles get stuck, you won't get enough gas in the bowls to get gas to the engine.  If you have cracks in the rubber connectors, your air fuel ratio is off and will make the bike run crappy.  I was running at 80 mph when that happened to me.  All of a sudden it seemed to lose power.  I had a hard time keeping up with traffic at 55.  Try both, and good luck.
Don

theunrulychef

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #2 on: July 23, 2006, 06:41:51 AM »
Kinda sounds like the carb rubbers, but not sure how they would have unsealed on their own - you said this problem started before you messed with it.  Perhaps the rust in your tank caused problems at first, then after pulling the carbs, the boots are now leaking - just a theory.

What condition is the battery & charging system in?

Offline KB02

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #3 on: July 23, 2006, 06:52:59 AM »
Have you done a compression test on it yet? Just corious as to what your compression is. Other than that, I would say, too, that it sounds like rubber issue.
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einsteingarage

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #4 on: July 23, 2006, 06:57:49 AM »
The rubber boots sound like they could be the culprit.

This is a long shot but....  I don't have much experience with street bikes only dirt bikes...so this could be a stupid response.  A friend had a similar problem on his dirtbike and it turned out to be the ground on his ignition coil was loose.  So it would run great then cut out or run choppy then cut out.  Tightened it up and it work fine.

Offline DammitDan

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #5 on: July 23, 2006, 07:02:07 AM »
I second, third, and fourth the carb boots.

Have you noticed your RPMs will refuse to go down below a certain level, and when you rev the engine it will either stick there or drop back very slowly?
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Offline 78_SaltLick

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #6 on: July 23, 2006, 07:11:26 AM »
I second, third, and fourth the carb boots.

Have you noticed your RPMs will refuse to go down below a certain level, and when you rev the engine it will either stick there or drop back very slowly?

yeah, what you mentioned happened right after I adjusted the needle in the carb abou a month ago, figured i just needed a sync after messin with the needles. The sucking sound happened right after i re-installed the carbs. like i said the bike does seem to be running better or should i say different than before, man if thats all it is im going to be one happy camper. How do i know which boot is sucking or loose or cracked? Theres like 16 places these boots connect to the carbs, i do know when i reinstalled the carbs some of the threads are still showing where the carbs meet the air box. just couldnt get it back on right.
Dumbest question in SOC history:

Would a vacuum leak (is that what you call air sucking from boots?) cause your bike to run like crap? (inconsistant idle, loss of power, sucking noise) I take it by your responses it would.

How do you determine where the leak is coming from? Could it be that i overtightened the screws? I have them really tightened down, before a few of them were pretty loose.

Dammit maybe im close, i sure hope so.
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Offline 78_SaltLick

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #7 on: July 23, 2006, 07:12:25 AM »
Kinda sounds like the carb rubbers, but not sure how they would have unsealed on their own - you said this problem started before you messed with it.  Perhaps the rust in your tank caused problems at first, then after pulling the carbs, the boots are now leaking - just a theory.

What condition is the battery & charging system in?

Battery is newer, i keep it charged up with a trickle charger, had the charging system checked seems to be pumping out the right amount to recharge the battery.
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Offline 78_SaltLick

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #8 on: July 23, 2006, 07:13:36 AM »
Have you done a compression test on it yet? Just corious as to what your compression is. Other than that, I would say, too, that it sounds like rubber issue.

no compression test....i would be curious as well. Something i need to do.
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Offline 78_SaltLick

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #9 on: July 23, 2006, 07:15:09 AM »
When you cleaned the carb float bowls, did you take off the floats and make sure the needles were cleaned, so gas could get into the bowls?  The other question I would look into, especially if you are getting a sucking noise, is what shape are your rubber connectioens between the airbox and carbs and carbs and engine?  I've had problems with both, and the engine has run horrible in each case.  If the needles get stuck, you won't get enough gas in the bowls to get gas to the engine.  If you have cracks in the rubber connectors, your air fuel ratio is off and will make the bike run crappy.  I was running at 80 mph when that happened to me.  All of a sudden it seemed to lose power.  I had a hard time keeping up with traffic at 55.  Try both, and good luck.
Don

i took floats off, cleaned out the needles and made sure the floats were all operational, meaning they moved freely. gas seems to be getting into the float bowls. Same level of gas in each.
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Offline paulages

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #10 on: July 23, 2006, 09:19:24 AM »
IMO an airleak at one of the intake rubbers would cause that cylinder to run lean and hot, not cool. also, you can't tweak your carbs and not expect to get away without a sync. some of the symptoms you are describing are indicative of this problem (inconsistent idle, different temps at the pipes).

did you set your floats heights properly? you could be starving that 1 cylinder of gas at an idle.
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Offline TwoTired

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #11 on: July 23, 2006, 11:28:17 AM »
You're not going to like this...
But, if it ran well for a while and then suddenly # 1 pipe is cool.  I'd suspect the slow jet in # 1 is plugged again.  Take off the bowl and check for light through the slow jet again.  It's just a guess that you didn't flush the fuel lines during your fuel contamination corrective procedure. As you know, thats a pretty small hole in the slow jet.  What's the phase? "The carbs have to be meticulously clean."

The sucking sound is likely an induction leak but it could be from either the intake side or the filter side of the carbs.  There are two bolts that mount the filter box to frame.  Remove those before fitting the rubber boots onto the back of the carbs.  This will allow them to move forward enough.  After the couplers are clamped into the proper place, then reinstall the filter box bolts.

You ARE close.  I mean you had it running well for a while, right?  You can do it again.  The learning process is not always fast.  Like most acquired skills; patience, practice and perseverance, prevails.

Cheers,
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Offline Tim2005

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #12 on: July 23, 2006, 11:55:09 AM »
Yep, I'd look at that carb again. And you can get #1 float bowl off without pulling the carbs.  As for finding airleaks, some people recommend spraying carb cleaner on the various joints while the engine is ticking over, apparently you can then hear the tickover change when you find the leak. Not tried that myself, and if you do it be careful the carb cleaner doesn't dissolve the paint off your crankcases, as some types do.

Offline g8ts

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #13 on: July 23, 2006, 01:55:35 PM »
Yep, I'm with tim spray carb. cleaner around boots, one at a time while bike is running, If idle goes up you found your leak.
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Offline mlinder

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #14 on: July 23, 2006, 02:19:39 PM »
When dying electrical heat up, they can act like this.
exceot the sucking noise. That sounds like a bad seal somewhere. Rubbers, as many others have mentioned. Get that fixed, the go through electrical.
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Offline 78_SaltLick

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #15 on: July 23, 2006, 10:16:07 PM »
Ah ha! yet another mystery.....my bike smells like gas sitting in the garage....didnt use to before i pulled the carbs out. today ii saw a small puddle of gas sitting under the drain tube that comes from float bowl #3, the tube that is routed under the bike....what does that mean? I know that means its overflowing with gas.....but why? I did take all the main jets and slow jets out of each carb and blow them out and reinstall them. Didnt mess with the floats on that carb though....why would gas be flooding that bowl?
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Offline TwoTired

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #16 on: July 23, 2006, 10:37:53 PM »
Well, it **COULD** be a little flake or spec if dirt blocking the float valve from closing.
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Offline jtb

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Re: Okay now im ready to throw this bike off the nearest cliff....help!
« Reply #17 on: July 24, 2006, 11:08:18 AM »
Spray WD-40 or water around the boots, not carb cleaner.
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