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post #1 of 9 (permalink) Old 10-07-2017, 12:16 PM Thread Starter
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Some help?

If the video works - can use a little help to determine what is causing the pop sound only out of front cylinder please.

Have had this issue with pipes before. It only seems to pop persay when bike is warm not when cold. I have worked with the air fuel mix etc. but in my wonderment if re jetting was required wouldn't both cylinders have same noise ( pop)?
I switched to the fish tails cause other pipes a bit loud, and not good for testing purposes. Any mechanic I have encountered chooses not to work on these bikes. Perhaps a little guidance from you if you get the chance.

Also as a bonus I notice i can run my bike fine with petcock off or on or probably missing lol...does that have anything to do with this?

thanks

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post #2 of 9 (permalink) Old 10-07-2017, 12:38 PM
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I'd say it's just a product of straight, loud pipes. Probably no amount of tuning would clear it up completely. You might adjust it a bit rich and clean it up, but then it's rich, burning your eyes, wasting gas, and fouling plugs.

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post #3 of 9 (permalink) Old 10-07-2017, 12:51 PM Thread Starter
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thanks that helps. I also recall on the stock pipes before any touch i had similar sound just not as noticeable due to the pipes themselves. But in fairness i think it was 30 minutes before I punched out the baffles on stock pipes. What you say makes sense thanks I appreciate it. The baffles on the fish tails are hollowed out as well. Curious though why would it only pop as it warms up?. Just common expansion of air flow due to heat?
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post #4 of 9 (permalink) Old 10-07-2017, 01:38 PM
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It's hard to hearit the way you can in person. To me it doesn't sound like a bad pop, such as a backfire. It's more just rackety or cackling pipes. I don't think it's anything that's hurting performance, just may be annoying to you?

Heat and fuel mix may contribute to only hearing it once it's warm. If it's only coming from the left side, it may be the length of that pipe.

If it was worse I might investigate for leaky valves, but I don't think that's happening from what I can hear. Having the goat belly might blend it better, but no doubt that's a big headache with the fishtails.

I'd say live with it or change the pipes/mufflers. Almost every VN with open pipes has a bit of pop to it.

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post #5 of 9 (permalink) Old 10-07-2017, 02:07 PM Thread Starter
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thats the phrase...annoying to me...thanks man. I just wanted to make sure that i am not creating harm. As you stated - back fire. The other pipes were shorter yet on the front cylinder side. But those I made chopped them up and kept baffles in. Not measured exactly but within four inches of each other. The tails are original length. That's why I have the question of why the pop or back fire- in which you seemed to have answered. Annoying to me..perfectly hit on point. Thanks
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post #6 of 9 (permalink) Old 10-07-2017, 03:08 PM
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Gives the idle some character,. I don't think it sounded bad when you revved it, has a throaty note. Need a video of going through the gears.

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post #7 of 9 (permalink) Old 10-07-2017, 05:52 PM Thread Starter
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I will try to get that video. So it is safe to say the petcock being in off position and it still runs fine is separate concern? Not affiliated? Also since the fishtails on, she seems to have loss of power at high rpms in first and second gear. When i revved it up in the video I wanted that crackle sound to arrive so it could be heard to determine if damaging or not. but it's not clear on the end of vid. thanks again
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post #8 of 9 (permalink) Old 10-07-2017, 08:16 PM
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The petcock shouldn't cause the pop, but there's something wrong if it won't shut off. Or someone has modified it. It shouldn't be a problem, until you need to shut the fuel off. Can end up with gas in the oil if the fuel happens to keep flowing through the carb, like a stuck float or getting gas through the petcock vacuum hose.

High rpm in first isn't really doing much, kind of going nowhere fast. I usually roll out, get moving in 1st, then wind the guts out of 2nd-3rd if I want to be quick. If you take 1st to high rpm, the trans is gnashing pretty bad going into 2nd. Got tired of hearing that klack so I take it easy in 1st now.

Opening the pipes usually takes away low end power/torque and adds a bit on top end. Could watch the plugs over time to be sure it's not lean.

2003-21k mi
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__________________________________________________ ____________
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post #9 of 9 (permalink) Old 10-08-2017, 09:07 AM Thread Starter
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that makes sense also..I might be pushing her to hard in the first two gears, especially since my ears are tuned into certain sounds. Plugs are read at the nice tan color on all four cylinders (currently). Thanks for the heads up. Once i do my end of year maintaining process I will check to see the petcock detail. At this point it seems fine.
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