Tone down exhaust

[SGCSCRX3]

Anyone here tried anything to tone down the exhaust on the Rx3? I wondered if one of those Db killers on ebay would help just a bit. Idle is fine just when I'm running At 7,000 rpm for a while it can be loud to me. I have a Yamaha 950 with a Vance and Hines and it's loud but a different kind of loud I guess.

[Working_ZS]

Originally Posted by SGCSCRX3

Anyone here tried anything to tone down the exhaust on the Rx3? I wondered if one of those Db killers on ebay would help just a bit. Idle is fine just when I'm running At 7,000 rpm for a while it can be loud to me. I have a Yamaha 950 with a Vance and Hines and it's loud but a different kind of loud I guess.

It may not be the exhaust, a lot of the noise that you hear while riding the RX3 (and RX4) is induction noise from the air intake. It gets exacerbated by the front windscreen, which catches and reflects it back at the rider. Unfortunately, if that is what you are hearing and find irritating, I'm not aware of any means apart from resonator cavities (used on a lot of car intakes) to try and reduce air intake noise. Here's a link to a pdf on the subject, you might find it interesting:

https://www.ijresm.com/Vol_1_2018/Vo...V1_I10_115.pdf

It deals mainly with using Helholtz resonators to reduce induction noise, which is responsible for about 30% of most noise generated by an internal combustion engine. The problem with that solution is that there is even less room on a motorcycle for an intake resonator cavity than there is in an automobile engine compartment.

[SGCSCRX3]

Interesting read. This makes me think of when I removed a similar intake setup from our 2006 Saturn Vue few years back. It really changed the sound under throttle.

[pyoungbl]

Just to amplify ZS's point, when at highway speed note how much noise you are hearing...then open the throttle suddenly. The noise increases immediately. The engine rpm is not changing nearly as fast as the noise level. That tells me that the noise is not exhaust note but intake. It was much more evident on my RX3 than the RX4. My RX3 is long gone but had I kept it I was planning to experiment with some kind of sound mitigation inside that small airbox.

[tknj99]

Originally Posted by pyoungbl

Just to amplify ZS's point, when at highway speed note how much noise you are hearing...then open the throttle suddenly. The noise increases immediately. The engine rpm is not changing nearly as fast as the noise level. That tells me that the noise is not exhaust note but intake. It was much more evident on my RX3 than the RX4. My RX3 is long gone but had I kept it I was planning to experiment with some kind of sound mitigation inside that small airbox.

Thats good to know with regard to noise on the RX4.. i dont plan on modifying the exhaust and want to e on the quieter side of things with long distance touring in mind.. the Brozz with the Ebay exhaust gets tiresome after awhile thats for sure

[Lukas]

On the left is a butylene patch, I used it to muffle the engine cover from the low tones that appeared when I built it up, in the middle is a piece of rubber car wiper I made it into a wall to muffle the air can on the right is a sponge muffling car self adhesive I taped on the air filter can from the outside rear wheel arch I lacked to tape the seats from underneath and the bottom of the fuel tank semi-synthetic oil muffles the clatter of the clutch basket and the motorcycle does not sound like a forage harvester.To quiet the valve cycles apart from wrapping the bottom of the tank with a sponge it helps a lot to wrap the exhaust with asbestos tape preferably 3 times otherwise the color burns out I have tested it by the way the exhaust gets very hot I am going to change the injection map and by the way check if the mixture is not too low using a glass plug.
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