Quiet muffler

[srvfan]

To me its a very deep baritone type drone just cruising with the wife at 20-35 ish. I was also wondering if maybe it would be cured with the barn of parts soft spring or other clutch kit that would lower the rpm while cruising slow. This sled turns lots more RPM then my Vector at slower speeds and uses way more fuel. maybe lowering rpm will cure all 3 issues. The odd part of the high rpm cruising speed is when hammered the thing doesn't turn more that 8400-8500 RPm . Almost like you've got to widen out the whole range . Engage and cruise at lower RPM and raise RPM on top . that's a whole nother topic though..... I'm curious has anybody put a db meter on the aftermarket exhaust ? It is possible that they could be quieter than stock ? no reason you couldn't build 1 like that and not give up power . I can't imagine the Doo 900 is giving up that much and they are extremely quiet.

 

[Mtnviper]

Yeah, it's the deep baritone drone for me too. Low frequency drone is hard thing to muffle sometimes.
I even went as far as buying a quiet ride helmet. It has ear muffs in it and helped reduce wind and high frequency noise. It didn't reduce the drone though, so I tried a set of active noise cancelling ear buds.
Wearing the active noise cancelling ear buds inside the quiet ride helmet totally eliminated it! However they are kind of a hassle to wear in a helmet and are not all that comfortable on long rides.
So next I modified and installed a set of Bose noise cancelling head phones in my quiet ride helmet.
The noise cancelling head phones eliminate about 90% of the drone, however if I pin the throttle the added sound over powers the microphone system in the head phone unit and turns them off while under WOT. I'm still kinda playing around with that set up to see if I can get rid of the WOT noise cancelling cut off.

It would be nice to make the sled itself quieter though. Basically there are two types of noise cancellation, passive and active.
Passive noise cancellation is normally done through sound absorption, such as using various types of packing. Passive noise cancellation is effective at reducing higher frequency noises but is typically not as effective at reducing low frequency (drone) noise.
Active noise cancellation is where a particular sound frequency is either reproduced (like in noise cancelling head phones/ear buds) or reflected (helmholtz pipe) back to the source. Since the sound waves are at the same frequency they cancel each other out. Active or reflective noise cancellation isn't as effective at cancelling out higher frequency sounds as passive noise reduction, however it is much more effective at low frequency drones. The trick in all this is to figure out what the Hz of the offending sound is and building a pipe the correct length that will fit under the hood!

 

[srvfan]

I have not ridden any viper with an aftermarket Can. It's possible that an aftermarket Can might actually seem quieter because it is harmonically different as far as the drone goes ?

 

[SRViperDoug]

I know this is a very old post, any fixes for the very annoying drone noise with the vipers?

 

[Derek Fosbury]

Thanks for bringing this thread to the top. One of the reasons I don't like my RS Venture is because of the drone. I had thought that the Vipers were much quiter, but this thread has me concerned about getting a '23 Viper. I was considering the Viper if it comes with EPS for '23, otherwise will get the Sidewinder LT-X GT EPS.

Any comments from folks with newer Vipers would be appreciated!

 

[SRViperDoug]

Thanks for bringing this thread to the top. One of the reasons I don't like my RS Venture is because of the drone. I had thought that the Vipers were much quiter, but this thread has me concerned about getting a '23 Viper. I was considering the Viper if it comes with EPS for '23, otherwise will get the Sidewinder LT-X GT EPS.

Any comments from folks with newer Vipers would be appreciated!

i am considering give the noise cancelling ear buds a try!