M8 Exhaust

[harleytuner]

It looks like Vance & Hines has a full line of exhaust out now for the M8's.  Power Duals in both chrome and black and about 7 slip on options in both chrome and black. 

edit*  I checked stock at a distributor, they are set to have them in stock in November.

[00se]

 I've been told that the aftermarket dealers will be introducing their M-8 products at Biketoberfest this year.

[hattitude]

Fuelmoto posted dyno sheets today. With an SE air cleaner, jackpot slip-on mufflers, and new jackpot 2-1-2 header... they gained 10HP & 10TQ over their baseline dyno on an M8.... they are working on their air cleaner and believe there is more to pick up....

They also said that on 9/26 the new firmware and tunes for the PowerVision to support the M8 will be available....

Things are looking up for this M8...

[Jako1]

The mufflers I am told have cats, the baffles are real short like my 15 had, you can knock the centers open with a screw driver, have some one hold the muffler on the bike so it does not move
The baffle plate looks like a flower petal folded in
Esay to do
The mufflers look the same as 16 models but are different part numbers

[hattitude]

The mufflers I am told have cats, the baffles are real short like my 15 had, you can knock the centers open with a screw driver, have some one hold the muffler on the bike so it does not move
The baffle plate looks like a flower petal folded in
Esay to do
The mufflers look the same as 16 models but are different part numbers

The M8 motors have the CAT in the headpipe, but it is farther towards the rear than the 14-16 models. This requires the right side muffler to have a larger diameter where it bolts to the headpipe....

[Jako1]

HMMMMM, my mufflers are way different, part number tho they are the same as my 15
The head pipes are different, the O2 sensors are there not in the cat

[PoorUB]

Hey Jako, do you know anything for sure about the M8 exhaust?

The whole exhaust is different from previous years. The cat is in the head pipe, the O2 sensors are in the head pipe, but mounted closer to the engine. The mufflers are different too.

[Jako1]

I stand corrected, 
I just knocked out my baffle centers
I wonder why the MOCO changed the part number on the mufflers other than the diameter  all else is the same cept the head pipes 02 sensors and moving the cat back, IMO a great idea for my wife 
Now I have a set of Stock 15 Freewheeler mufflers I cannot use   

[Hossamania]

The Moco changed the part numbers because they are different mufflers.

[bluerim]

I just had my suppertraps taken off a 2013 triglide and installed on a 2017 triglide.

[Jako1]

The Moco changed the part numbers because they are different mufflers.
Copy that

[SP33DY]

I got an announcement from S&S yesterday. They have "high performance" M-8 mufflers ready to ship. "50 state legal".

https://www.sscycle.com/search/#category=1%7CMufflers%20%26%20Exhaust&diameter=4.5%22

[harleytuner]

got a message from Zipper's yesterday.  They will have Rinehart slip ons in stock very soon as well.

[Tommy D]

I got an announcement from S&S yesterday. They have "high performance" M-8 mufflers ready to ship. "50 state legal".

https://www.sscycle.com/search/#category=1%7CMufflers%20%26%20Exhaust&diameter=4.5%22

If memory serves me right, The MK45 is a different animal than their Race Tour.. IMO 4" Race Tour had a better tone

[calif phil]

I just had my suppertraps taken off a 2013 triglide and installed on a 2017 triglide.

Did you have to modify them?

[92flhtcu]

Trike mufflers are the same from 16 to 17 as the cross-over is unique, at least I've had several dealers tell me this

[BVHOG]

Rinehart slip on's are out and V&H stuff, including a Power dual is scheduled at Drag for Nov 8

[Buglet]

    Is anyone working on a 2 into 1.

[freddie_ray]

This is just my opinion, but I really hate the 4 inch and bigger exhaust mufflers. I'm going back to the 3.5 

[Tommy D]

This is just my opinion, but I really hate the 4 inch and bigger exhaust mufflers. I'm going back to the 3.5 

C'mon now, Fat is where its at 
http://www.phatperformanceparts.com/BUB_Design_Boom_Can_Slip_on_Mufflers_for_Harley_Da_p/d5-1002c.htm

[Rokinrider]

I liked my 3.5" Rinehart on my 16, waiting a few months to see what comes out this winter!

[George W]

https://www.youtube.com/shared?ci=4UMhqWns9mE

[Jammer53]

https://www.youtube.com/shared?ci=4UMhqWns9mE

If I was to buy one, the Kerker Stout Slip-ons sound the best to me. Deep rumble.

[saafrican]

JAKO1   you said that you knocked out the barrel centers of the mufflers ?
Did you notice   an difference  performance wise ?

Ive fitted a SE air filter to my M8RG 
The person who designed the standard M8 air cleaner needs to be fired .
Ive seen bigger air cleaners on a 125 scooter , never mind a 1750 cc engine
Really disgusting design work, especially from a professional design team ,
Who approved that crap 

Anyway I rode my bike with the new SE air cleaner , bike seem to be a lot smoother ?

Im after a less restrictive exhaust system  NOT NOISE
and don't see the value of noisy $500 slip-ons  or any cost benefit vs performance gains .
I would like to see dyne curves   standard  vs slip ons only . a straight shoot out

To complement the larger SE air cleaner I need to open up the exhaust system .
Ive listened and watched youtube videos of removing the baffles and fibers glass packing .
But those pipes are too loud for me ( Im okay with loud pipes , just not on my touring bike )

So tonight t bought a 41mm HOLE SAW  ( it just fits into the exhaust pipe end) and cut the restrictive center of the baffles out .  (Similar to what JAKO1 did , but with more finesse , no hammering , sorry Jako )
It took me 10   or 15 min  to do both sides .
It was to late to go for a ride , the bike was a little louder , but not obnoxiously loud .

With the SE air cleaner   and a less restrictive exhaust pipe ,I expect to notice some performance
improvement .
Tomorrow Ill take it to the HARLEY dealer  to  flash the CPU with stage 1 harley tune .
Ill report back .

NOW   looking into the pipe I can see a catylitic converter, smiling and tempting me to attach it ?
mmmmmm  stay tuned

[Nastytls]

    Is anyone working on a 2 into 1.

D&D has one.

[DRod]

saafrican,

let us know how you make out.  I have the 17 SGS w/stage 1 (SE street cannons and heavy breather intake, SE tuner) but was also considering a cat removal.  it doesn't look that difficult.  I don't want to cut and weld like others have done.  it needs to remain clean and stock looking.  if I can't do it then maybe i'll do the American Custom Exhaust header swap for $199.  I believe it's called the powerflex system.  they replace your stock header with another stock set that's been modified.  (they don't just remove the cat)

[tomcat64]

we did our first one a couple of weeks ago,, SE 447 cam, V&H power dual head pipes  with Rinehart 4" slip-ons and TTS tune,, made 94.42HP and 112.39TQ

[Glide17]

I would have thought there would be a bigger difference with a decatted head pipe. I have the cannons stock head pipe ventilator and 447 cams se street tuner and I got 109 tq 92hp. Apparently Harley did a good job opening up that Cat and getting more velocity in that pipe. It works more like a 2-1 than a 2--1-2 looking at how little exhaust exits the left pipe and the angle at which it has to go to exit.
Still like to lose the cat just for heat purpose alone

[tomcat64]

we got 84 and 104 with the stock head pipe,,

[Glide17]

Well that's a good gains  with that pipe then.

[saafrican]

Hi Guys .
This is what I have done .
SE stage 1 air cleaner , amazing improvement
SE  stage 1 ECU tune , to keep the air fuel mixture right .
I used a 42mm hole saw and cut open the standard exhaust tail end cap.
The 42mm hole saw just fits into the opening . Once the end piece is drilled out , the exhaust pipe has no restrictions . None at all . Its possible to look inside and see the catalytic  converter inside the collector box .  Take a SE Cannon , its the same , STRAIGHT THROUGH .

According to Harley the SE stage 1 kit increase the torque to 107 at 3500 rpm (that is 85 MPH )
Doing the above costs about $600 including the ECU installation
I did NOT buy Big  Cannons , little cannons . S&S  Fuelly Pipes  or any other pipes because they are around $500 $600 , and make more noise

Harley SE stage 2 costs $2500 ,and increases torque 1  maybe 2 ft/lbs   but at higher  revs   i.e. 3750rpm    Heck thats  90mph    WHO CRUISERS AT THOSE SPEEDS 
I can't justify $2500 for 2 ft/Lbs torque increase yes the torque curve is flatter   but for $2500  
NO THANKS    to expensive for not much useable torque .

With only the tail section of the exhaust pipe cut out ,Ive gained the benefit of an open exhaust pipe  and saved $550

The other big advantage for me ,  there isn't an obnoxious noise increase , It is a little deeper ,but NOT RAUCOUS , because I haven't removed any sound proofing from the exhaust pipes .

Because Ive done SE modifications Ive kept the Harley warranty , Saved $550  and gained max Torque/dollar

To ride.?
MAN THIS BIKE IS NICE   there is so much pulling power right from idle .
The most noticeable is from 1000 to 2000 RPM .

From 60 mph  when you  crack the throttle open in 6 th gear the bike is VERY strong and the road get narrow real fast .

IF you thought the M8 is nice !!!!   do these fairly cheap mods  and you will really love your Harley 

[Sunny Jim]

So clearly the M8 header is different to it's predecessor.
With the advent of aftermarket exhausts eg. Fulksac and Fuelmoto, will the previous model slip ons fit the new proposed headers from manufacturers like formentioned suppliers. Any clues?

[Jamie Long]

Our M8 Jackpot head pipe uses 2017 specific mufflers with the larger right hand inlet and was designed as such.

[Partsman64]

    Is anyone working on a 2 into 1.

I talked to Vance and Hines.......They said a new Propipe would be available probably late spring, early summer.   

[wumhenry]

Why pay for aftermarket M8 headpipes?  Wouldn't you get essentially the same thing by decatting the stock pipes?   

[Sunny Jim]

I am looking at this M8 header and thinking this thing is really modelled on a 2-1. It's like the left pipe does very little. Any thoughts?

[DRod]

interesting.. I did a muffler swap and only made a slight improvement in performance and sound.  While doing the swap I examined the cat and thought about drilling right through it.  has anyone considered this to allow more air flow?  I don't think you need to completely remove the cat.  doing so will also eliminate whatever back pressure is required. (assuming some back pressure is required) But by allowing more air flow wouldn't it give you better sound and probably better performance that stock? 

I'v got my long drill bit standing by! 

[rigidthumper]

I'd think exhaust flow could be disrupted by the crushing action action of a drill bit.  Maybe try a long core bit of the right diameter to remove the cat?

[DRod]

not looking to remove it completely.  just trying to allow a bit more airflow.  If we do need some back pressure than we may still need this piece in place.  opening it up a bit may help with sound and performance.  I read someone had completely removed the cat only to discover the bike lost pressure and thus power.  Can anyone confirm this?  will removing the cat altogether create a problem?  obviously I'll need to retune, but i'm talking in addition to that..  I want to start off slowly.. 

[rigidthumper]

So far, it hasn't proven to be a restriction. I've seen testing with the stage 3 kits, stock headpipe, slip on mufflers and SEAC make almost 120TQ and 115HP, and be EPA/CARB/DOT legal.

[Sunny Jim]

A dealer , here in Western Australia, has been installing 09 - 16 after market slip ons with a manufactured reduction sleeve on the RH exhaust outlet. Allegedly discontented owners have been having heat and blown head gasket issues on these exact bikes. Another dealer has been replacing head gaskets and exhausts with no further issues!
Any thoughts?

[slimatsea]

So clearly the M8 header is different to it's predecessor.
With the advent of aftermarket exhausts eg. Fulksac and Fuelmoto, will the previous model slip ons fit the new proposed headers from manufacturers like formentioned suppliers. Any clues?

Bassani true dual down unders are out now and they fit the 95-16 slip ons. I'm really tempte to go othat route because I hate the look of the factory fat right muffler but I'd be really pissed if I bought headers and lost performance. I don't have much faith in true duals to make great power.