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Added quiet cores, not sure if bike is supposed to sound like this.

2927 Views 19 Replies 8 Participants Last post by  CodeInVB
I have Cobra dragsters on my bike. In their stock core form they are LOUD. I picked up a couple of Cobra's quiet cores to quiet things down a bit and billet tips to dress things up. I had a heck of a time getting the cores in, to the point that I had to put a stick of pine on them and tap them into place...so they're a tight fit.

Here come the questions and where my confusion is. My bike now runs at a sound level that I'm happy with but I can now hear this kinda whining sound when I accelerate. I'm not sure if it's normal and always been there or not, like I said, the pipes were loud and drowned out everything else when the engine was on. Is this type of sound normal for a mean streak?

The reason that I'm questioning is that the cores were tight going in but the tips that I ordered were not even close to fitting. According to Cobra's site, the pipes are supposed to be full length 2.5" heat shields, my pipes are 2.25" OD. They have Cobra stamped on them and the cores that I removed definitely looked like the regular cobra cores.

Anyhow, is "whining" normal on a quieted down mean streak or am I now giving this thing too much back pressure?

Thanks.
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I have Cobra dragsters on my bike. In their stock core form they are LOUD. I picked up a couple of Cobra's quiet cores to quiet things down a bit and billet tips to dress things up. I had a heck of a time getting the cores in, to the point that I had to put a stick of pine on them and tap them into place...so they're a tight fit.

Here come the questions and where my confusion is. My bike now runs at a sound level that I'm happy with but I can now hear this kinda whining sound when I accelerate. I'm not sure if it's normal and always been there or not, like I said, the pipes were loud and drowned out everything else when the engine was on. Is this type of sound normal for a mean streak?

The reason that I'm questioning is that the cores were tight going in but the tips that I ordered were not even close to fitting. According to Cobra's site, the pipes are supposed to be full length 2.5" heat shields, my pipes are 2.25" OD. They have Cobra stamped on them and the cores that I removed definitely looked like the regular cobra cores.

Anyhow, is "whining" normal on a quieted down mean streak or am I now giving this thing too much back pressure?

Thanks.
Man I can't remember, but you may have some transmission whine. It it gets louder when you get off the gas, you may have the front bevel gear bearing going out. Or you may hear a little final drive noise.
Keep an eye (or ear) on it, Colin has experience with the Bearing problem. On the other hand you commented you heard the whine under "accleration". Is it possible your hearing the sucking of an aftermarket intake. I can hear mine occasionally, kind of a weird hiss when I get on it.
Keep an eye (or ear) on it, Colin has experience with the Bearing problem. On the other hand you commented you heard the whine under "accleration". Is it possible your hearing the sucking of an aftermarket intake. I can hear mine occasionally, kind of a weird hiss when I get on it.
If it is the bevel gear bearing, it will get louder
No after market intake yet. I've got one to put on but haven't done so yet. I'll ride for a bit and try to get some better Intel on it.

Thanks for the input.
CodeInVB you want to get together this weekend maybe go for a Run Summer is coming to an end and i need to get in the Wind as much as i can before i start the modding madness all over again. Your not afraid of getting out run by a Middle aged Women are you. LOL Seriously though if you want to go for a Rip hit me up. Maybe i can give you some insight on what you got going on.
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If I can break away from the wife and kids. It may have just been that I wasn't used to the sound. The bike is a lot more quiet now but still growls when I get on it.
If I can break away from the wife and kids. It may have just been that I wasn't used to the sound. The bike is a lot more quiet now but still growls when I get on it.
Ok the Growler it is That is so much Better than typing CodeInVB you are now the Growler. LOL
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works for me.
No after market intake yet. I've got one to put on but haven't done so yet. I'll ride for a bit and try to get some better Intel on it.

Thanks for the input.
The man wins a free intake, and doesn't even put it on. SHAME SHAME
I started taking the tank off to get the fuel controller in...wanted to do that first...and ran out of time... :corner

I really want to get it put on Paul...honest.
Shoulda sent it to me Paul, It would be on!!! :)
sooooo....back to the original topic. I recorded the sound and the more I hear it, the more I think it is how the bike is supposed to sound. Again, my exhaust was so loud that it was all that I could hear before.

Here's a link to the file. Sound It's about 500k total.

The sound I'm talking about kicks in around the 10 second mark once I started moving the bike.
Still curious about this so I'm gonna *bump*
Sounds like you're hearing the intake whine. I have Hard Krome 3" straights and my bike sounds the same, only LOUDER! I would suggest taking the baffles out and enjoy the sound! :headbang:
Sounds like you're hearing the intake whine.
Yup, I think you were right. I took the time today to throw on the cobra FI, reed block plates and the sweet Bad Ace Billet intake that I won. The whine is gone and now I can hear the intake sucking in the air when I hit the throttle. Pops and backfires are gone too now and the bike has a lot more pull.

Pics of the intake will be coming soon!
sooooo....back to the original topic. I recorded the sound and the more I hear it, the more I think it is how the bike is supposed to sound. Again, my exhaust was so loud that it was all that I could hear before.

Here's a link to the file. Sound It's about 500k total.

The sound I'm talking about kicks in around the 10 second mark once I started moving the bike.
Mine sounds exactly like that and always has. That is not the front bevel gear bearing. From my experience, that's just normal mechanical whine from the Vulcan engine.
sooooo....back to the original topic. I recorded the sound and the more I hear it, the more I think it is how the bike is supposed to sound. Again, my exhaust was so loud that it was all that I could hear before.

Here's a link to the file. Sound It's about 500k total.

The sound I'm talking about kicks in around the 10 second mark once I started moving the bike.
sounds normal to me
Thanks. That's what I figured, but I wasn't sure.
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