Cheap air box that works

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Winterwolf
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Re: Cheap air box that works

Post by Winterwolf » Sun Apr 02, 2017 10:42 am

Was the popping noise in that video?... I couldn't really hear it if it was?

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Re: Cheap air box that works

Post by jhalfhide » Sun Apr 02, 2017 10:51 am

Winterwolf wrote:Was the popping noise in that video?... I couldn't really hear it if it was?

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It sounds to me like a different pitch burble that fades in and out.


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Re: Cheap air box that works

Post by kevxtx » Sun Apr 02, 2017 11:19 am

When you ride these 990's with an open air box at part throttles around 3000rpm there is a noise that is emitted from the air box area, the noise is when the inlet & exhaust valves are over lap, meaning the inlet & exhaust valves are open at the same time for an instant, the noise is a hollow beating type of noise, the noise is normal & is baffled by the OEM air box.

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Re: Cheap air box that works

Post by Tommy » Sun Apr 02, 2017 1:23 pm

jhalfhide wrote:That's really weird, you haven't accidentally clicked SAS on or something have you and it's trying to do something with the engine?
I don't think so but I will check that when I get the chance.
jhalfhide wrote:
Winterwolf wrote:Was the popping noise in that video?... I couldn't really hear it if it was?
It sounds to me like a different pitch burble that fades in and out.
Yes, popping is maybe not the correct word to describe it but you can clearly hear the sound coming and going in the video. It is even more noticeable in reality.
kevxtx wrote:When you ride these 990's with an open air box at part throttles around 3000rpm there is a noise that is emitted from the air box area, the noise is when the inlet & exhaust valves are over lap, meaning the inlet & exhaust valves are open at the same time for an instant, the noise is a hollow beating type of noise, the noise is normal & is baffled by the OEM air box.
We still have some snow left here so I haven't had the chance to properly ride the bike yet, but I have already noticed the noise at 3000rpm. That I can live with but the noise at idle is really annoying. You think it is of the same reason? If I remember correctly map #20 has a bit lower idle than original. If I am lucky the noise will go away if I change it back to original. It is a small difference so I doubt it. Weird that I am the first one to experience this.

Btw. I didn't have to adjust the valves so this is not because of messed up valve timings. I don't think it is anything harmful to the engine, but I still would like to get it fixed.

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Re: Cheap air box that works

Post by rob53 » Tue Apr 11, 2017 8:58 am

Tommy I have exactly the same mods and tune on my 990 and as far as I can tell the same noise. When it starts from cold and the revs are up a bit it burbles with the richer mixture until the temp comes up. Also get the noise on a neutral throttle when the engine isn't loaded.
I haven't really been able to hear the note from the Wings cans since the mods but like the intake roar not to mention the extra power and smoothness on full throttle.

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Re: Cheap air box that works

Post by Nordic09 » Tue Apr 11, 2017 3:56 pm

I have map 20# and other tricks with rottweiler but std exhaust. At 3k there is that hollow burbble, but the idle is normal. With std exhaust the intake sound at the city is enormous at full throttle. From noice point of view no aftermarket exhaust is needed.
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Re: Cheap air box that works

Post by jhalfhide » Tue Apr 11, 2017 9:18 pm

Nordic09 wrote:I have map 20# and other tricks with rottweiler but std exhaust. At 3k there is that hollow burbble, but the idle is normal. With std exhaust the intake sound at the city is enormous at full throttle. From noice point of view no aftermarket exhaust is needed.
I've the same and it's made me even consider leaving my exhausts standard [FACE WITH TEARS OF JOY]


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Re: Cheap air box that works

Post by Tommy » Wed Apr 12, 2017 2:56 pm

I did some more testing yesterday. Pinching the crankcase breather hose makes the noise go away. After reading discussions about oil change in this forum I started to suspect that I had put too much oil in the engine and that oil was pushed up the hose. I checked the 4l oil bottle and there was about 0,5dl left.I then checked the oil level after running the engine and it was exactly at the full mark.

I guess a better dampening filter would help. This is what I have now: http://www.biltema.fi/sv-fi/Bil---MC/Bi ... 000032870/

I think I will ride it as it is to start with and see if I can live with it. Still waiting for my wideband lambda before I start riding. I want to make sure I don't damage the engine. I have also ordered a Wings exhaust that Im waiting for.

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