RLV Mufflers

[Harquebus]

I've seen these around but every single one seems short on technical description and high on price and for those prices, {$40-$50-$60+} I'd expect stainless steel or triple chrome plating or something: https://rlv.com/exhaust/4-cycle/4-cycle-silencers/

So what's the deal on the insides of these?
They look like nothing more than a steel tube with a perforated end cap welded on. Some end caps have tiny holes and some have a square mesh or diamond mesh on the end.

ETA: this one appears to have more than one baffle; "RLV 4106 muffler, Open Modified"

Basically I'm just asking for a review and if anyone knows what the innards are comprised of. Thanks

 

[creia]

my .02 cents....
In my experience (used to have one on our Bonanza BC1200 (with a somewhat upgraded Briggs Raptor engine) they are over-rated, over -priced and under-perform from a sound quieting standpoint. They are just one (small) step better than an open pipe as far as reducing sound. Technically, I believe they are actually a "silencer" , not a "muffler". Do they look cool? - Yes.
Michael

 

[Harquebus]

Hey, wait a second. There's an $18 dollar option in their lineup, #EXF4115.

I'm looking for a slip-on, no weld solution for a 1" pipe I have that's too loud. I think I will go this route just to find out
for myself and as an alternative to the ubiquitous $8 Briggs #294599.

 

[toomanytoys]

I ended up brazing a 3/4" conduit coupler the last header and using a hot dog muffler.

It was a 100 times quieter than my rlv slip on

 

[Mark Brooks]

Where I'm at, quieter draws far less attention. Don't need any attention drawn unnecessarily!

 

[creia]

Hey, wait a second. There's an $18 dollar option in their lineup, #EXF4115.

I'm looking for a slip-on, no weld solution for a 1" pipe I have that's too loud. I think I will go this route just to find out
for myself and as an alternative to the ubiquitous $8 Briggs #294599.

It is going to be LOUD- you've been warned!
Michael

 

[Harquebus]

It is going to be LOUD- you've been warned!
Michael

Bummer. I thought it provided a decent tidbit of noise reduction.

The drone of the exhaust at cruising speed isn't what's so bad, it's actually the backfiring {actually *after*-firing} on deceleration--> BAM-B-B-BAM, BAM-POW-CRACKLE! You can mitigate it somewhat by not just releasing the throttle, but slowly backing it down until you get to the stop sign.

I guess it's off to the 3/4" coupler and Briggs sausage muffler. I know what those are like.

 

[toomanytoys]

I ride in my yard a reasonable amount. My tillotson with a straight pipe was deafening loud. I didn't realize how loud it was until my dad took it down the road the minibike pavement loop is 1/2 mile down. Turn around at the gas station and back up. I heard him all the way down the road, let off to turn around and all the way back.

Pops, crackles and booms all the way around.

 

[I74]

I took the ''way'' cheaper RLV 91, cut off some of the threaded end, & bored the crap out of it.
It breath's real good on my GX-200, with a 3 stage pipe ect., & also helps on bottom end torque.
That pipe stock would be to restrictive though.
It's pretty quiet, & has a ''nice'' higher pitch also,, unlike the ''raspy'' - ''much larger'' RLV one on my Buddies Tillotson 212, with a 3 stage pipe,,, that I also set up.

 

[Harquebus]

I ended up brazing a 3/4" conduit coupler the last header and using a hot dog muffler.

Not trying to be daft, but can you post a link to what you used or a photo? If you gewgle "3/4" coupler", the hits are astronomical in terms
of item material and purpose. Thanks.

 

[toomanytoys]

Not trying to be daft, but can you post a link to what you used or a photo? If you gewgle "3/4" coupler", the hits are astronomical in terms
of item material and purpose. Thanks.

https://www.amazon.com/dp/B000VYFJIS?ref=ppx_pop_mob_ap_share

I used this. It was galvanized. Used a wire wheel to clean it off. Not sure what it was made of. I'm not great at it but I was able to braze it on. Not ideal but it was the only thing I could find that wasn't cast.

The threads seem to be a straight pipe thread instead of a tapered thread like a normal pipe fitting. But the muffler screwed in fine with a little playing and hasn't came off yet.

 

[FlatheadDon87]

From my very experienced perspective the rlv silencer does exactly as claimed. Also going from an open pipe to one of these your engine will need to be rejeted for maximum performance. Usually 2 numbers higher for the 90 which is designed for wka class type engines with rules and the 91 is for wka open classes. They are designed to reduce decibels to a excepted amount with out hindering power. And if set up correct they do just that, and sometimes if tuned can even add power. BTW I'm new to the forum and hope I can be of help and learn things as well. An open mind prevails.

 

[Harquebus]

Thanks for the reply, but I have seen no claims as to what these silencers are purported to do, such as an expected decibel reduction or something typical, if not precise. I also asked about interior construction {baffles and how many} and again, there are no specs.

Welcome to the forum. If you're coming from a performance or racing background, you may find yourself 'overqualified' here as most in the vintage minibike scene are content to putter around at marginal speeds "re-living" their youth or what it was like then. In a word, nostalgia.
But that's not everyone by a long shot.

 

[FlatheadDon87]

Thanks for the reply, but I have seen no claims as to what these silencers are purported to do, such as an expected decibel reduction or something typical, if not precise. I also asked about interior construction {baffles and how many} and again, there are no specs.

Welcome to the forum. If you're coming from a performance or racing background, you may find yourself 'overqualified' here as most in the vintage minibike scene are content to putter around at marginal speeds "re-living" their youth or what it was like then. In a word, nostalgia.
But that's not everyone by a long shot.

That's exactly what I do as well. I will show you the article when I get home on the rlv muffler. As far as baffles go they are simply screens. The 90 has 4 screens Identical to the small hole screen as the end. The 91 or modified has three of the round hole screens like the 90 buy the fourth one at the end has diamond shaped openings. I'll check mine out when I get home it's possible the 91 also has bigger holes in the first 3 screen but am not positive. To reply to what else you wrote. Yes I do come from a performance background but honestly that makes no difference. WOT or putting around on the governor, wouldn't change the fact that there is right or wrong answers. Also I have seen a few of the performance questions on this forum that are incorrectly answered, or answered partially. Apologies if I questioned anyone's intelligence. That being said I do not and will not post anything unless I know it is a fact, unless I state it is an opinion or an assumption. Only trying to help folks get the most out of there experience. In no way am I trying to start an argument or make someone look foolish. Thanks for the welcoming to the forum. Glad to be here.

 

[FlatheadDon87]

Here are a few things to support the theory.

 

[FlatheadDon87]

 

[FlatheadDon87]

 

[FlatheadDon87]

Here is a picture of the silencers I bought from RLV. The suare one is the one for modified engines and the round holed one is for stock. To answer my question on the hole size yes the holes on the m91 are bigger than the m90 holes on the 3 inner screens

 

[FlatheadDon87]

I disassembled the m- 91 for your viewing pleasure. the m90 is basically the same except it is 4 screens with only small holes. I hope this is the what you were asking about as far as specs. Dimensions are: pipe over all length- 7 1/4 in x 2 1/4 in, screen od 1.125, thickness .035, diamond hole .270, big round hole .190, small round hole .125. If I missed anything let me know and I'll get it corrected.

 

[Harquebus]

I need that book, or catalog.

You'd figure something more in-depth would be offered on their very own site {RLV}. Such info may in fact be there, but I overlooked it.