Remove Catalytic Converter or Not !

[floridaman1398]

I am new to this site...so if this question belong to another forum, please let me know...

Anyways, I purchased my 2017 SGS in August. I am pondering and brooding over the question to whether or not remove the catalytic converter. But before we get to the answer, let me comment on the upgrades I have done and those that I will be performing in a month or so....

I have a pair of Vance and Hines Hi Output Slips-Ons

I will upgrade the engine from 107 to 114 (stage 3 Kit) next month and I will also put a SE Ventilator with a K&N Filter

I will also have a SE Street Tuner with it.

I purchased an extra set of stock headers that I will remove the catalytic converter and keep the other untouched just in case I don't like the catalytic removal, put the stock one back again.

Hence is the question, would I cause any damage to the engine by removing the catalytic converter?....

Is it worth decatting in order to gain more HP and Torque?

With the above set up, what would the be approximate hp and torque without the catalytic converter?

Any other advice will be greatly appreciated

 

[hulkss]

If you are using the street tuner, I would leave in the catalytic converter. The tunes you can download were developed that way and made for the stage 3 kit. Your bike will run fine, it's not worth decatting. Your engine torque may actually go down without the converter.

 

[floridaman1398]

If you are using the street tuner, I would leave in the catalytic converter. The tunes you can download were developed that way and made for the stage 3 kit. Your bike will run fine, it's not worth decatting. Your engine torque may actually go down without the converter.

Good Advice, Thanks !!

 

[2017 SG]

I did the sage 3 and just couldn't stand the way it sounded though I did try for a few thousand miles with using CFR's as mufflers. I finally got the Fuel Moto header and my dealer tried very hard to tune it but as we all know now (I got one of the first M8's) it just can't be done. I got a TTS and had it tuned by Gene Thomason who has worked closely with the developer of TTS for years (he suggested Gene when I called them to buy the product and he just happened to answer the phone and was very helpful). The difference in the bike after that tune was very drastic. Though I did love the bike before the tune I did not love the performance even with the stage 3 (stage 4 was not available when I got the bike) as well as hating the sound. Noe the bike not only sounds terrific but runs amazing, night and day different.
My dealer had me keep stock header and mufflers as well as Street Tuner and will install and flash back if necessary down the road with big issue. Obviously I have a great dealer (especially considering I am in CA) who knew I was never going to be satisfied with the stock setup with the Harley tune.
To be fair it really comes down to riding style and personal preference. Not that it is smart or mature but I have never got over 5000 miles out of a rear tire on my Harleys (also have a 2012 Roadglide with 60,000 miles) or broke 35 MPG unless on a group ride (which I usually avoid) so it makes sense for me. Many of my buddies spend a fortune on their performance of their Harleys and then worry about MPG and tire longevity and ride for that which I think is nuts. Not crazy that it is their riding style which I really should grow up and emulate but that they spend the money and risk reliability when it really doesn't change the way they ride their bike.
If you ride hard, ditch that cat and Harley tuner fast and save yourself frustration, if not then keep it all stock with the stage 3 and cat in and save yourself money and brain damage.
I say all of this humbly and just my opinion..

 

[NGOT8R]

My brother bought a 2017 CVO Street Glide last October and he started out with the HD Street Tuner and had his stock exhaust decatted. I actually took the stock header to my buddy (for my brother) and watched him perform the entire decatting process, which consisted of cutting the pipe in half, drilling out the cat and Tig welding the pipe back together. He then installed a pair of SE mufflers with the decatted header and while the bike sounded a little better, it just did not perform to his satisfaction. He ended up buying a V&H Power Duals header and V&H mufflers. He also ditched the SE Street Tuner and bought a V&H FP3 tuner which he absolutely loves. In addition, we installed a Wood 222 cam in it a couple of months ago and now it sounds amazing. Here is a short video clip of the bike at idle with a couple of throttle blips.

https://youtu.be/okPoYK4y6Pg

 

[hulkss]

Here is the fueling map in the HD download tune for the stage 3 114" kit.



It is well designed and is plenty rich for good performance, drive-ability, and power. Do not remove the cat, no dyno tune is needed, and you will be fine.

You will have lots of power and torque and keep your warranty.



From the tuning file:

Application: 2017-2018 Touring
Configuration: Milwaukee-Eight™ 107 to 114 Stage 3
Components:
- SE Air Cleaner
- 107 to 114 Stage 3 Kit
- SE8-498 Cam
- SE Exhaust

 

[floridaman1398]

Is good information !

My intent is not to have a racing motorcycle. My main use is riding with my lady around.

I always wanted a "little" more power to move two bodies around and when needed, press the gas and feel the power.....hence, the upgrade......

 

[2017 SG]

Is good information !

My intent is not to have a racing motorcycle. My main use is riding with my lady around.

I always wanted a "little" more power to move two bodies around and when needed, press the gas and feel the power.....hence, the upgrade......

I would take hulkss advice..

 

[Roadshark]

When I read Hulkss post my brain hears Gandalf .
I listen.

 

[Mojo]

I did the whole exhaust Dyno thing on my Rushmore ($1,800)but this time around I did a simple stage 1 with the FP3 and I'm happy and my wallet is a bit fatter.

 

[MKA_5966]

Unless it's about saving some cash, why wouldn't you just install aftermarket head pipes? I would think a stage 3 setup would perform much better.

I'm planning on doing the stage 1 over the winter months. It's more about reducing some of the heat than the small power gain. V&H Power Duals, FP3 and high flow breather of some sort. Only thing I'm pondering over is the slip-ons. Continue running the SE Street Cannons I have, or possibly some type of 4.5" V&H slip-ons. The Cannons have a perfectly matched slant with my CVO Bags.

 

[floridaman1398]

Unless it's about saving some cash, why wouldn't you just install aftermarket head pipes? I would think a stage 3 setup would perform much better.

I'm planning on doing the stage 1 over the winter months. It's more about reducing some of the heat than the small power gain. V&H Power Duals, FP3 and high flow breather of some sort. Only thing I'm pondering over is the slip-ons. Continue running the SE Street Cannons I have, or possibly some type of 4.5" V&H slip-ons. The Cannons have a perfectly matched slant with my CVO Bags.

I most likely will follow the advice of not taking off the catalytic converter.....As a young man in the distant past, I learned to listed to older, wiser, knowledgeable folks and as most of you may notice, I am not very knowledgeable about doing upgrades to Harleys, hence my pleas for advice.

Well....In regard to your question about the aftermarket head pipes....I think, and most likely I am wrong, but my thinking is that, as an example, the Vance and Hines X pipes and stock headers without catalytic converter would be the pretty much the same concept with just few minor differences, wouldn't that be the case?

Also, I will add that I just acquired the SE8-515 High Lift Cam and I will plan to put it on the bike when I do the "heart enlargement surgery" sometime next month on the bike.

I don't know how much power this set up would bring, but I hope is good enough to make me grin with excitement.

So, so far, this is what I have:

Stage III kit (114 c.i. jugs, pistons, springs, seals, tapers, gaskets)
SE8-515 High Lift Cams
Vance and Hines Hi Output Slip Ons
SE Street Tuner
SE Ventilator with K&N Filter


I would love to CNC Port the heads and add bigger injectors and intake but it is too expensive for me, so at least, with the stage III I think there would be enough juice to play with this toy.

 

[BluesBelly]

Unless it's about saving some cash, why wouldn't you just install aftermarket head pipes? I would think a stage 3 setup would perform much better.

I'm planning on doing the stage 1 over the winter months. It's more about reducing some of the heat than the small power gain. V&H Power Duals, FP3 and high flow breather of some sort. Only thing I'm pondering over is the slip-ons. Continue running the SE Street Cannons I have, or possibly some type of 4.5" V&H slip-ons. The Cannons have a perfectly matched slant with my CVO Bags.

The Street Cannons open up after several thousand miles and I think they sound great. The information I have garnered indicates the HD street cannons are made by Vance & Hines for HD. Comparing muffler cores of Street Cannons and V&H Twin Slash rounds reveals similarities.
Fuel Moto makes A great air intake that uses a K&N style filter and the stock cover and at a reasonable price point.
My 2014 SG stage 1 with the above muffs and intake as well as a stage 1 HD dealer ECM flash and stock cat head pipe runs a tad bit cooler and will out run a stock M8 for what that's worth.
Keep the Street Cannons and after awhile if you feel the need to switch up then go for it.
Good Luck,
Blues

 

[hulkss]

Also, I will add that I just acquired the SE8-515 High Lift Cam and I will plan to put it on the bike when I do the "heart enlargement surgery" sometime next month on the bike.

That 515 cam will get you more power but at the expense of a lot of torque below 4500 RPM (stage III vs stage IV):



My bike has had a high rpm power cam in it for two years now and I am switching to a "torque cam". I'm just not running above 4500 rpm enough. I'm typically passing cars at 3000 to 4500 rpm (55 to 85 mph in 4th gear) rather than 4000 to 6000 rpm (60 to 90 mph in 3rd gear). Although I must say the third gear pass to red line with a high rpm cam is a rush.

 

[Mojo]

Torque cam is more popular right now than the Power cam. I have a friend that discovered what you mentioned Hulkss, He then AGAIN sprung the $$$ and switched it out for Torque cam benefits/

 

[MKA_5966]

The Street Cannons open up after several thousand miles and I think they sound great. The information I have garnered indicates the HD street cannons are made by Vance & Hines for HD. Comparing muffler cores of Street Cannons and V&H Twin Slash rounds reveals similarities.
Fuel Moto makes A great air intake that uses a K&N style filter and the stock cover and at a reasonable price point.
My 2014 SG stage 1 with the above muffs and intake as well as a stage 1 HD dealer ECM flash and stock cat head pipe runs a tad bit cooler and will out run a stock M8 for what that's worth.
Keep the Street Cannons and after awhile if you feel the need to switch up then go for it.
Good Luck,
Blues

Thanks for the input. I really do like the Cannons. They have like you stated come into their own with a few thousand miles on them. I may try the route you took before spending the cash on head pipes. I have actually been looking into the Fuel Moto offerings. I really like the high flow intake and the head pipes. I'm still leaning towards the FP3 as the tuner at this point. Thanks again...Mike

 

[floridaman1398]

Well..

This is an update in regard to the newly installed Stage III...... Although the dealer did not provided me with the Dyno sheet, I can atest that the power the bike now has is insane.....I put the SE8-515 Camshaft, SE spark plugs wires, 114' kit.....and I love every minute of it....and I love the way it sounds....is a complete badass.......I plan to put the Stage IV down the line when the warranty expires... but as of now, I am very please with the bike.

I would say that the power is felt at around 25-2700 RPMs and up..And is so strong that in 5th gear, hauling my wife in the back seat....I twist the throttle a little bit and the bike wants to throw my wife out of the back seat....

I don't know the specs yet since the dealer did not gave me the spec sheet, but they told me that I will need to bring the bike again after riding for 1,000 miles so they can tweak and adjust.....but as soon as I have the specs sheet, I will post it in here.....

 

[floridaman1398]

I need advice from the Gurus !!!

I did a stage 3 upgrade few months ago. The set up is the SE 114 kit, SE 515 Power Cam, Vance an Hines Hi Output slip-ons, SE Ventilator, SE Spark Plugs wires. After the upgrade, I was told to ride it for 1,000 miles then to bring it back to do the 1K miles check up and put the bike back on the dyno to "refine" the set ups.

I did that and when I picked up the bike, I was handed the dyno sheet.....the dyno results were as follows:

Before Dyno: Max Hp: 98.99 Max Torque: 92.50

After Dyno: Max Hp: 106.65 Max Torque: 107.08



I don't think something is right. I believe that the numbers should be a lot higher than that. I mean, the bike right out of the lot should have 111 lbs of torque and now, it is 4 lbs less with a bigger engine and a different cam.....

Even the bike feels different...before you could feel the spunkiness, the power, and now, it is almost like when I first took it out of the dealer...tamed, somewhat sluggish...to put in different perspective, in 5th gear, I could twist the throttle a little bit and the bike almost wanted to trow my lady out of bike....and now....it feels not quite the same.....

Any advice what should I do?

Should I take the bike to a different techs ( not Harley Davidson morons and have them re-dyno my bike?

Advice and inputs will be of great appreciation !!

 

[NGOT8R]

I think you've probably just gotten used to the 114, although, a couple of things could account for the slightly lower dyno numbers.

1. Fuel used (quality may not have been what it was the first time in the dyno)

2. Low rear tire pressure (pressure should be at recommended pressure or slightly higher)

3. Heat soaked engine (if you rode the bike to the dealer and immediately strapped it to the dyno)

 

[floridaman1398]

I think you've probably just gotten used to the 114, although, a couple of things could account for the slightly lower dyno numbers.

1. Fuel used (quality may not have been what it was the first time in the dyno)

2. Low rear tire pressure (pressure should be at recommended pressure or slightly higher)

3. Heat soaked engine (if you rode the bike to the dealer and immediately strapped it to the dyno)

Very unlikely... I dropped the bike at the dealer. They performed the stuffs the next day. So the bike shouldn't be heat soaked. Since they also performed the 1K check up, the tires pressure should be already verified.

I only and absolutely use 93 octane fuel. Same fuel from the same place, Sunoco.