M&K MKM29 - Street vs Sport Question

[fallingat120mph]

I am about to purchase an MKM29/MKM29ST and was wondering just how loud the sport version is compared to the street version. In person I have only heard the MKM33 so no comparison to the exhausts I am looking at.


Some of the videos, with sound examples, are a bit dated and I guess my biggest concern is waking up the neighbors early in the morning, etc...

I do ride a motorcycle, old BMW 1200GS, so not a stranger to exhaust noise but just want to make sure my small town here in the midwest, and my wife, are not put off by the loudness.

I drive the 911 a lot and across country quite a bit so leaning towards the street....but...feel I will regret not giving the sport versions a go.

Either way a win, just wondering for a 90% street driver if the sport might be a little too much especially on my state to state travels...


Thanks!
Erik

[jac1976]

Get the sport and baffle and/or cap for longer trips.

[gsxrken]

I’ve come around after 40 years of fast cars and bikes that, when presented with a toss up like you have, go with the conservative option. Whether that’s cams, carbs, exhaust, spring rates, gearing… unless it’s predominantly a track toy, the way you use the car 95% of the time should dictate the selection.
Note: I wouldn’t blame you for ignoring me- I didn’t follow this advice for most of those 40 years either. It’s a process most need to go through for themselves.

[shoooo32]

How handy are you? Do you have a garage/tools? Before I had an electric actuated muffler, I used to swap them before road trips. Loud and rowdy at the track or around town and a cheap, stockish db level for road trips.

[MrBonus]

Originally Posted by gsxrken

I’ve come around after 40 years of fast cars and bikes that, when presented with a toss up like you have, go with the conservative option. Whether that’s cams, carbs, exhaust, spring rates, gearing… unless it’s predominantly a track toy, the way you use the car 95% of the time should dictate the selection.
Note: I wouldn’t blame you for ignoring me- I didn’t follow this advice for most of those 40 years either. It’s a process most need to go through for themselves.

Well said.

I'm 45 now and 10 years ago I would have put on the loudest exhaust I could find. I have the M&K dual-in, one-out and my car is plenty loud when it needs to be but manageable at normal operating RPMs.

The dual-out exhausts I've heard are raucous. They sound great at cars and coffee but I wouldn't want to drive anywhere with them for an extended period of time and I'd probably have an email from my neighbors if I used them outside of the hours of 9 - 5.

[jac1976]

Again, it’s easy to place baffles in the pipes and/or cap a single pipe. Best of both worlds.

[Funracer]

I am an early adopter of the MKM29ST. Really like this muffler. It’s perfect for my around town driving. My loud exhaust days are over. Wanted something tamer than the Sport version.

The tone has changed a bit since initial install. I specifically wanted to stay away from raspy sounding exhaust. Lots of owners love raspy. Not me. This muffler was a bit raspy for the first couple of hundred miles and then the tone gradually changed to the deeper growl I was looking for.

Secondly, it seems to have gotten a bit louder since I first put it on in 2021. I wanted something just one step louder than OE sound. It was that in the beginning but seems stronger now. Of course this is subjective. I am super happy with the ST version but if you make a lot of long trips you may need a plan to deal with that extra noise. Headphones? A/C on? I have a Cab and no AC so windows or top are always down.

If you end up with the Sport version and decide its too much, you can always sell it here and recover most of your investment. Good luck.

[Showdown]

I had the sport version and after the first 15 minutes of driving with it newly installed, the drone was so strong that it nearly made me sick. It was also too loud to leave my neighborhood early in the morning without waking everyone up. I installed baffles and silencers and never looked back.

Your mileage may vary, but I'd never drive one of those again.

[tobluforu]

Get the street version and make your ears happy, as well as your neighbors. I had the dual out, center, MK. One of the original ones and it literally set off alarms in parking garages. That lasted one year.

[fallingat120mph]

Originally Posted by jac1976

Get the sport and baffle and/or cap for longer trips.

This was my initial thought. Researching that aspect.

Thanks!

[fallingat120mph]

Originally Posted by gsxrken

I’ve come around after 40 years of fast cars and bikes that, when presented with a toss up like you have, go with the conservative option. Whether that’s cams, carbs, exhaust, spring rates, gearing… unless it’s predominantly a track toy, the way you use the car 95% of the time should dictate the selection.
Note: I wouldn’t blame you for ignoring me- I didn’t follow this advice for most of those 40 years either. It’s a process most need to go through for themselves.

Never ignore a solid answer. Well stated. 35ish years here of bikes and cars and I am at that crossroads where I know the answers to the things before I ask them in my head...but sometimes do not like the answers I provide myself - so I come here for the collective wisdom.

Originally Posted by shoooo32

How handy are you? Do you have a garage/tools? Before I had an electric actuated muffler, I used to swap them before road trips. Loud and rowdy at the track or around town and a cheap, stockish db level for road trips.

Handy enough for sure and this seems like the final option down the path.

Thank you both...

[fallingat120mph]

Originally Posted by Funracer

I am an early adopter of the MKM29ST. Really like this muffler. It’s perfect for my around town driving. My loud exhaust days are over. Wanted something tamer than the Sport version.

The tone has changed a bit since initial install. I specifically wanted to stay away from raspy sounding exhaust. Lots of owners love raspy. Not me. This muffler was a bit raspy for the first couple of hundred miles and then the tone gradually changed to the deeper growl I was looking for.

Secondly, it seems to have gotten a bit louder since I first put it on in 2021. I wanted something just one step louder than OE sound. It was that in the beginning but seems stronger now. Of course this is subjective. I am super happy with the ST version but if you make a lot of long trips you may need a plan to deal with that extra noise. Headphones? A/C on? I have a Cab and no AC so windows or top are always down.

If you end up with the Sport version and decide its too much, you can always sell it here and recover most of your investment. Good luck.

I read that same response in a few other threads...seems like selling the one I don't keep will not be a problem down the road.


Thanks-
Erik

[TimT]

Its easy enough to tune the muffler for the intended use.... caps, baffles, turndowns

Mine is a Gen 1 M&K RSR muff with M&K headers... all it takes is a few minutes.. and I can pass sound at Lime Rock... (86db) Or remove the sound attenuation... and the set up screams... (my shift point is 8200 in low gears)

[SkunkWorks]

Used to have a 2-out M&K sport - with both sides uncapped it was terrible, with 1 side capped it was ok but not what I was looking (listening?) for.

Back to a 1-out now and it is exactly what I've wanted all along. Sound clip is with 41mm SSI's:

https://youtube.com/shorts/rUO3_ABGfDY?si=c97gdwmaGtaocf1O

[Balisong]

I bought MK Headers and a single street exhaust. 15 minute first ride….removed the street ..way to quiet. Asked if I could get a sport but it wasn’t being made at the time due to materials. Sold the street and bought a Scart. It mated to the MK headers just fine.
Very, very happy.
https://youtu.be/k32GiQqxd_A?si=1bCdacJB8fyIpWBv

[fallingat120mph]

Does anyone have a photo from the top down on how far the two exhausts hang out the back? I see the M&K are 8 inch tips. The videos here/YouTube aren't very helpful...am looking at older threads but coming up empty.

Thanks for any side/top down photos in advance.

EDIT: My storage units has a drainage dip right in front of it and it's already close with front and back as the car has been lowered a bit...my home drive where this stays at times was constructed with a bad angle also...

Erik

[jac1976]

I can snap a photo later today

[fallingat120mph]

Originally Posted by jac1976

I can snap a photo later today

Awesome...thanks.

Much appreciated!


Erik

[mb911]

Originally Posted by TimT

Its easy enough to tune the muffler for the intended use.... caps, baffles, turndowns

Mine is a Gen 1 M&K RSR muff with M&K headers... all it takes is a few minutes.. and I can pass sound at Lime Rock... (86db) Or remove the sound attenuation... and the set up screams... (my shift point is 8200 in low gears)

Dang that’s one I made in my garage all those years ago.

[RarlyL8]

Sound level preference is in the ear of the beholder, which is why we offer a lot of options.
M&K Sport mufflers are loud enough to not pass 92dB limits on some tracks.
M&K Street mufflers were designed to pass track regs and European and California sound regs by getting just under that number at full throttle.
The mufflers can mix and match accessories allowing the user to tailor the sound level to their liking. Baffled tailpipes that are standard on the street muffler can be used with the spot mufflers. Internal caps that are options for the sport mufflers can also be used with the street mufflers.
The 8" tailpipes tuck up under the bumper of a G-body, sticking out just past the license plate. We have a 5" version for the early cars that can also be used on the G-body if desired. This is an older picture but shows the placement of the tailpipes in relation to the bumper.