Crappy ride
05-01-2009, 03:27 PM
#1
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Crappy ride
Well I finally got my bike running half way decent, rode it for a few days, then out of the blue it starts running like shyte. surging while cruising, coughing at any rpm at any throttle position. Just running like ***. 
Why have the motorcycle gods forsaken me?? I'm hoping it's something simple, but I took the carbs off and moved my needle one position leaner, and changed my plugs, and its still the same. (I didn't try to fix the issue with the needles it was just something I had been meaning to do.) I was hoping maybe a vaccuum line slipped off or something, but having reinstalled everything I doubt it. It idles fine btw. And thoughts?
Why have the motorcycle gods forsaken me?? I'm hoping it's something simple, but I took the carbs off and moved my needle one position leaner, and changed my plugs, and its still the same. (I didn't try to fix the issue with the needles it was just something I had been meaning to do.) I was hoping maybe a vaccuum line slipped off or something, but having reinstalled everything I doubt it. It idles fine btw. And thoughts?
05-01-2009, 03:44 PM
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Well I finally got my bike running half way decent, rode it for a few days, then out of the blue it starts running like shyte. surging while cruising, coughing at any rpm at any throttle position. Just running like ***. Why have the motorcycle gods forsaken me?? I'm hoping it's something simple, but I took the carbs off and moved my needle one position leaner, and changed my plugs, and its still the same. (I didn't try to fix the issue with the needles it was just something I had been meaning to do.) I was hoping maybe a vaccuum line slipped off or something, but having reinstalled everything I doubt it. It idles fine btw. And thoughts?
Why have the motorcycle gods forsaken me?? I'm hoping it's something simple, but I took the carbs off and moved my needle one position leaner, and changed my plugs, and its still the same. (I didn't try to fix the issue with the needles it was just something I had been meaning to do.) I was hoping maybe a vaccuum line slipped off or something, but having reinstalled everything I doubt it. It idles fine btw. And thoughts?
why did you do all that and not check your TPS? it's often responsible and usually off if it hasn't been set recently or ever. Once you get it set, it's usually good for a long long time. When you take your tank off, make sure that the little vacuum pipe under the tank on the left top side of the petcock has a hose on it and not the one facing down(which gets no hose). Happy days are coming if you do your homework!
05-01-2009, 04:09 PM
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well that's good. what did you set the TPS at? I wonder if you may have pinched a diaphram when changing the needle setting. Look at you plugs to see if their burning correct color. Maybe the needle should be put back to original setting? Maybe it upset your configuration relative to jetting, air filter, pipes? These engines seem very sensitive to small changes sometimes.
05-02-2009, 12:16 AM
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The tps was at about 850, so I turned it as much as I could without bending or drilling, and it went to about 550, but like I said, it ran fine and then something suddenly went wrong, so unless my carbs rejetted themselves while I was riding, I don't think thats it. And the plugs looked fine, and as I said I even threw two more in for good measure, no change.
05-02-2009, 05:06 AM
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The tps was at about 850, so I turned it as much as I could without bending or drilling, and it went to about 550, but like I said, it ran fine and then something suddenly went wrong, so unless my A rejetted themselves while I was riding, I don't think thats it. And the plugs looked fine, and as I said I even threw two more in for good measure, no change.
Once you get the TPS right(closer to 450 acc to others-you can feel it), if there is still a problem, i would go back and undo the needle change and see what effect it has. Make sure the carbs are seated on the rubbers good and they are tightened. It's definitely something stupid. These carbs are finickey.
05-08-2009, 10:35 PM
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Alright, I have made little progress, other than narrowing it down to the rear cylinder. I unplugged the rear coil and the bike ran fine on the front cylinder, obviously no power, but generally smooth. And then I tried the rear and it stumbled all over. So I have gone through the carbs three times. Everything looks pristine. All vacuum lines are accounted for. Brand new spark plug, redid the shitty wiring to the coil. still runs like crap on the rear. Tomorrow I am going to swap around the coils, but aside from that, any ideas?? Keep in mind it's only on one cylinder and is at all rpms under any throttle position under load or not. And it happened SUDDENLY while riding, so it isn't a jetting issue or a tps issue or a worn this or that. That would have gotten gradually worse. Something gave. Thoughts?
05-10-2009, 09:42 PM
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My hopes were dashed... Well The primary resistance on both my coils is 1.2 ohms. And they are dyna coils btw. (.5 ohm) Well the front showed a resistance of 12k on the secondary side the first time I tested it, and i checked the rear coild and it said OL so I figured it was toast. But when I rechecked the front, it said OL too! so now I can't get any resistance reading out of the secondary side of either coil. I am going to try an old coil I have lying around to see if it helps any... thoughts?
05-10-2009, 10:52 PM
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If you are using a digital autoranging VOM to measure that, pressing the blunt probes to contacts while reading resistance often gives bad readings. For resistance reading try to use aligator clip ends on a least one of the probes... or make several measurements to get an average if they are floating all over the place.
05-11-2009, 12:42 AM
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Swapping the coils seemed to change the cylinder problem, despite both coils giving the exact same resistance readings, even when I heated them up with a heat gun. I'm a broke student, so I'm weary to drop $150 for a new coil when it tests good... I'm no shotgun mechanic. What I really want is try a new coil for a spin around the block before I buy it... hehe I wonder if I can convince my local parts guy to go for that...
05-11-2009, 07:41 PM
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It's probly a broken wire inside the coil. I've seen this in relays in some a/c units do this. it wont work right but checks out ok. the wire could be broken and still touching. Just a thought.
05-13-2009, 06:37 PM
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The primary coil is the two terminals on the bottom, both checked out at about 1.2ohms, even when heated, and the secondary is between the plug post and either of the two terminals on bottom. They must share an iron core or something. The bike seems to be running ok all of a sudden though. I'm gonna keep riding it until it quits, beings I'm a poor student.
05-19-2009, 07:21 PM
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So I got some coils from a car, and it ran EXACTLY like it did with the dyna coils. Cutting out and sputtering. The coils always tested good, but when I swapped cylinders the problem swapped with them! What the hell is the issue???
05-19-2009, 09:22 PM
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Plug wire or cap? How about the wiring harness on the coil? That's the only thing that would pass over to the other cylinder yet still possibly give a good test of the coil.
My bike was running like **** last month. I did have some carb problems too, but idle was crappy even after cleaning them. Anything over idle was pretty much normal. The last time I pulled the carbs for cleaning I discovered the cap was loose on the wire to the rear cylinder. The caps screw on and that one had backed off and finally just fell off. The end of the wire was charred to hell from arcing. I snipped off about a cm and screwed it back on. Now she runs as smooth as ever.
My bike was running like **** last month. I did have some carb problems too, but idle was crappy even after cleaning them. Anything over idle was pretty much normal. The last time I pulled the carbs for cleaning I discovered the cap was loose on the wire to the rear cylinder. The caps screw on and that one had backed off and finally just fell off. The end of the wire was charred to hell from arcing. I snipped off about a cm and screwed it back on. Now she runs as smooth as ever.
05-19-2009, 10:01 PM
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I left the plug wires on their respective cylinders, and I redid the wiring to the coil on the rear when it was having the problem, it did nothing. I have no idea why it switched to the front... but I can rule out the coils now that I replaced both of them and it persisted.
05-20-2009, 01:45 AM
#24
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In the case of evil spirits, try voodoo.
Get a chicken bone, any chicken bone ( KFC bone will work )
Hang it over the bike by a red string ( must be red )
And chant obscure Tibetan chants ( have to look them up for you )
while holding a candle.
This all must be done at night.
Ive seen weird stuff like this actually work on unexplainable situations.
Get a chicken bone, any chicken bone ( KFC bone will work )
Hang it over the bike by a red string ( must be red )
And chant obscure Tibetan chants ( have to look them up for you )
while holding a candle.
This all must be done at night.
Ive seen weird stuff like this actually work on unexplainable situations.
05-20-2009, 09:19 AM
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perhaps two of your 4 coils are bad? We are kind of running out of options here :P
05-20-2009, 11:09 AM
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05-20-2009, 08:38 PM
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there's probably nothing seriously wrong, but something stupid that you're not seeing. I hope you figure it out soon,
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