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Vulcan S Delkevic 410mm exhaust too loud

14K views 22 replies 11 participants last post by  Hayds  
#1 ·
Hi all,
I recently bought a Delkevic slant cut exhaust after listening to it through some YT videos.
I really like the overall styling but the sound volume it produces is just obnoxiously loud to me.
Does anyone know of a way to make the exhaust any quieter, the baffle is still in.
I don't want to just instantly throw the exhaust out seeing as that it isn't the cheapest modification for a motorcycle.
 
#4 ·
I ended up going with the 550mm which is definitely not as loud as the 410mm. If you want to improve the sound and less deafening , you should pack it with exhaust fibreglass packing.

I did this a while ago and only have this picture but essentially...

If you tap out the muffler from the casing with a screw driver and mallet, it will slide out of the casing.

Fill the interior with exhaust packing and keep it in place with some wire or metal zip ties, pack it in and around the silencer as well (The middle part that is removable inside).

Fit and test the sound, you will be able to remove or add more packing to your acquired taste.

It made my exhaust less "droney" and more of a deeper tone.

Check my signature for useful links

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#11 ·
Hello everyone. I immediately ask you to forgive me for my English. And so, my solution to the loud exhaust is this. I bought fiberglass, wires and fiberglass mesh on Ali Express. I disassembled the muffler ( you can find it on the Internet ) , took out the baffle and wrapped it in fiberglass, then wrapped it in a fiberglass mesh and wire on top ( before that I tried to wrap it just in glass wool and secured it with metal ties , but after 300 km all the cotton flew out ) . The sound has changed, the more layers you make, the quieter the sound will be, but in power you will lose. just choose the right number of layers for yourself.
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#12 ·
I have the same exhaust and also thought it to be too loud. Even with earplugs.

I put this thing:
before the muffler.

I needed to wrap it with aluminum tape to prevent rattling as this thing's OD is smaller than mufflers ID.

Can hear it with helmet & earplugs on, but >50mph and wind noise starts to take over. Idle is nice. Only moments when I feel it's too loud in when accelerating hard in 1st or 2nd, going almost right to the redline. Had taken ~1.5h road trip max since and didn't have issues with ears ringing / headache.

Just another option to try.
 
#13 ·
I have the same exhaust and also thought it to be too loud. Even with earplugs.

I put this thing:
before the muffler.

I needed to wrap it with aluminum tape to prevent rattling as this thing's OD is smaller than mufflers ID.

Can hear it with helmet & earplugs on, but >50mph and wind noise starts to take over. Idle is nice. Only moments when I feel it's too loud in when accelerating hard in 1st or 2nd, going almost right to the redline. Had taken ~1.5h road trip max since and didn't have issues with ears ringing / headache.

Just another option to try.

I ordered Style 2, and will report back my findings... it has smaller holes than the one you are using...
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#21 · (Edited by Moderator)
Reporting back: Ok, following user ferrisnox's method, I installed this dBKiller into the Delkevic muffler while keeping the baffle. The results were the best I could hope for: it's much quieter, while still a far jump over the OEM exhaust.

It seems cutting nearly an inch off the baffle with a hacksaw is required to install both items into the muffler. For those wondering, it's the engine-facing side of the baffle that you cut if that wasn't obvious. As for trying the dBKiller without the baffle, that was a net-neutral at best. No quieter, no louder. I don't recommend that as a solution to anything for anyone, just a solid waste of time.

Now for the non-scientific testimonial:


Idle:
Delkevic: Very loud, nearly have to yell over it in conversation. However, it has a deep rumble that matches the bikes performance.
D+dBKiller: Loud, but not so that you'd have to shout over it. The deep rumble remains, but now the mechanical engine chatter makes up for more of the sound. Couldn't ask for more.

Low-RPM, stop sign to stop sign:
Delkevic: Once you reach 4k RPM in 1st or 2nd you are fully in "That jerk” territory. Sounds mean at any RPM, but you're just doing 20mph. Honestly, a bad look and rude. Not so if you manage to keep it around 2-2.5k RPM
D+dBKiller: Unless you roll her WOT or exceed 6k, it's not too loud for the unprotected ear. 2-4k has enough noise for a luxury vehicle to still hear you, but I will admit some of the charm is gone from the tone of the exhaust.

Maximum Thrust:
Delkevic: Sounds PISSED OFF and throaty. However, it's 120dB+, enough to damage anyone's hearing unprotected. Above 6k it was almost too loud for me with earplugs and full-face on.
D+dBKiller: Sounds moderately angry above 5k, definitely well below 120dB and no bother to me with protection. Again, the tone and resonance don't have the full sex-appeal of the stock Delkevic, but a worthy trade-off.

Cruising 40-70mph:
Delkevic: Too damn loud to the RIDER at 70mph. 40-55mph in 6th was fine, but sitting in 5th at 40mph kinda pounded the skull.
D+dBKiller: Can comfortably cruise at a lower gear when necessary, making it less annoying when going between stop lights. I always wanted to shift into the highest gear possible before, which isn't great for emergency acceleration situations.

In summation, while this new combo doesn't have all the aural sex appeal that the Del 410mm did stock, it maintained the most important parts: Sounds good and mean above 4-5k when you roll hard, idle sounds loud and throaty enough, and engine braking sound still tickles that good part of your brain. What I gained was a much more pleasant bike to ride for myself and others!
 
#23 ·
I did the same thing like ferrisnox and InflammableUser. I ordered the same shape db killer from Aliexpress for 10 Euro. Cut 25mm off the baffle’s open end to free up space for the db killer. It was rattling a bit and chatgpt told me to use soda can tin to shim the gap and snug the fit. 2 layers of soda tin around the perimeter where the db killer meets the pipe eliminated the rattle.

It sounds amazing! No more hearing fatigue after riding the bike without plugs. The loud obnoxiousness has been tamed. The bike is not mute by any means, still sounds angry, has some nice bark and is popping on decel like before. I would say it is 80-90% as loud.

Thank you guys for the idea!