Author Topic: help please asap  (Read 856 times)

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Offline vintageacat

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help please asap
« on: August 06, 2013, 10:40:09 PM »
hey there. my bike was running great. I put new points and condensers in it and gapped them at .015 and it ran excellent. anyway today driving to work it ran like a raped ape. then all of a sudden it started sputtering and running terrible. anyway my bike is sitting at a bar parking lot and I need it to run right. it tops out at 45 and sputters and backfires. but yet it still starts by a simple flick of the wrist on the kicker. Idropped all the bowls and they were good and clean. I'm sure it's a electrical issue. it's mostly on both inside cylinders by what I could tell from plug color and the backfire flames. anyway this is my main form of transportation and I need it.running asap. I only get a few sick days a summer and.I'm taking one to get this thing out of the bar parking lot and to get me to work. btw this is.a great site and good people. I'm not a newb to motors at all. but I'm just overwhelmed by this.because I'm not working on it in my garage and this should not be happening. it's also a 75 model. thanks

Offline cougar

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Re: help please asap
« Reply #1 on: August 07, 2013, 06:20:41 PM »
vintage ; You say that you just put in New points and condensers. I'ld check to make sure that All the places where a wire bolts/screws on are tight. It sounds like 1 of your wires is a little loose and has slipped around enough to start grounding out. Since it initially ran Great and now is messing up that would be where I looked. Hope this helps.   ...cougar...
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Offline phil71

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Re: help please asap
« Reply #2 on: August 07, 2013, 06:30:43 PM »
Sounds an awful lot like you're running out of gas.

Offline BobbyR

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Re: help please asap
« Reply #3 on: August 07, 2013, 06:36:55 PM »
Check that your condensers are properly installed. You could have some arcing going on.
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Offline madmtnmotors

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Re: help please asap
« Reply #4 on: August 07, 2013, 06:40:20 PM »
I'd say cougar is on track. Problem with 2 AND 3 would point to points/condenser/coil adjustments or connections. Points can be static timed with surprising accuracy, at least close enough to run fairly well. I use a cheap multimeter to align the timing mark with the break in continuity across the points. This simple check would at least show you if your points had shifted. If timing is still good, then check connections between points and coils, voltage at the coils, etc. If you have the old condensers you might even swap one out for the 2-3 condenser to rule out a faulty condenser.
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Offline rb550four

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Re: help please asap
« Reply #5 on: August 07, 2013, 07:00:12 PM »
Does it run any better with the points cover plate off ? What position is your choke in? Was the points screws tightened enough,did the gap change or timing slip, static retest them both for time? Have you lubricated the spark advance,and sure  that it is able to advance ( is it free to twist, did a spring break maybe?). Could you have installed a faulty condenser? Are your plug caps screwed into the wires? are all cylinders  firing ( look for the cooler exhaust pipe).
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Offline phil71

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Re: help please asap
« Reply #6 on: August 07, 2013, 07:08:52 PM »
If it ran really great right after, and you know fuel flow is happening, check the tiny screw holding the condenser and coil wire to the points.
  I've recently had a cheap aftermarket condenser fail after a few days, and that was a real head scratcher. You can move the condenser wires around to see if the problem moves.

Offline BobbyR

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Re: help please asap
« Reply #7 on: August 07, 2013, 07:09:11 PM »
If you can do 45 you can get home if you are not far from home. I have had this happen. sounds like you have two cylinders out.
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Offline Vincent P

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Re: help please asap
« Reply #8 on: August 07, 2013, 07:15:57 PM »
Use a screw driver in the spark plug wire trick and see which set of wires are not firing. It seems as though either 1/4 or 2/3 coil is not getting energized. If using this old trick leads you to one set of coils not firing, I'm willing to bet that the points energizing that coil has slipped out of gap i.e. close. Reset the gap and I think you should be fine!!! Good luck...
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Offline Bootlegger56

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Re: help please asap
« Reply #9 on: August 07, 2013, 07:38:51 PM »
I agree with the above.  Take another look at what you were working on last ie points and condensers and make sure you haven't left one of the condenser nuts loose or grounded it out by accident.  If you saved the old condensers you could also try swapping them out.  Recheck gap and timing and see what happens.
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Offline martin99

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Re: help please asap
« Reply #10 on: August 08, 2013, 03:59:22 AM »
Just a thought.

I have always been taught that 99% of fuel problems are electrical, so it follows that 1% of electrical problems could be fuel...

Are the clamps nice and tight on the inlet to carb boots? An air leak could give very similar symptoms.
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Re: help please asap
« Reply #11 on: August 08, 2013, 06:21:08 AM »
Keep it simple like said all ready go back to what you worked on last " I put new points and condensers in it and gaped them at .015 and it ran excellent" I had a set of points slip. I snugged it up and did not go back and tighten it up as it began to shift or move it started sputtering just like fuel.

Offline Vincent P

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Re: help please asap
« Reply #12 on: August 08, 2013, 06:31:17 AM »
Keep it simple like said all ready go back to what you worked on last " I put new points and condensers in it and gaped them at .015 and it ran excellent" I had a set of points slip. I snugged it up and did not go back and tighten it up as it began to shift or move it started sputtering just like fuel.
Reason for my earlier post; the same thing happened with the new points I put on at the start of this summer. First ride after the installation, power dropped, and sputtering, made me think I needed to switch to the reserve position on the petcock.
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