M8 performance upgrade

[Sunny Jim]

I have jumped on board and got me a M8 RG. It is different but I really like it. Has anyone carried out regular performance upgrades on the new M8?
Has it been a successful transition regarding smoothness and power?
Is there an aftermarket intake available yet? 

[To The Max]

Hey Jimbo, what size is the throttle body .

[Sunny Jim]

Not sure but I think possibly 55mm.

[bluerim]

The Harley Heavy Breather is about as good as you can get.   It is a screaming eagle product. p/n 39400263.
dyno testers claim it to be better than no breather at all.  Some tests claim to actually make more tq than no a/c at all.

[lightblue37]

you might want to try nick trask. he has shops around the country

[saafrican]

I wanted my bike to look standard so I've fitted a screaming eagle AC to my m8 ,
From a design point the std and SE filter elements are totally different . The SE is three times bigger .
How Harley could even  fit the std ridiculous filter is a sin ,it is so small .you will be horrified at the piece of crap .
The SE filter housing opening is huge compared to the std housing , the front doesn't have the rectrictive gauze , and the bottom of the housing is open .
The SE unit is suitable for the new 114 motor so will easily flow enough air for a modified 107 .

I wanted to install a stage 2 kit
But looking at the toque curves ,I've decided to only do stage 1
The M8 is geared to do 3500 rpm  @ 80mph
Max Torque for stage 1. 106.@3500rpm  Price $650
Max Torque for stage 2.  107@ 3500rpm. Price. $2500

At the moment (nov2016) there are no header pipes for the M8 , which should change those torque figures by flowing more air in an out ,
So I'm going to remove the cat converter .
But instead of cutting a flap in the collector box , I'm going to remove the right side muffler and try and remove the cat with a 3"?? Holesaw and a pry bar / scraper .
Failing that. I'll cut the header pipe on one of the existing collector welds , remove the cat and weld the pipes together again . Welding on top of a thick weld is easier that welding thin flat metal . And visually you shouldn't notice that the collector has been modified . Also be aware that the header pipes are made from stainless Steel , so you need to have the correct welder and wire .

With all those mods the bike has to be retuned .
To keep the warranty you have to re flash with a SE tuner .
I don't know how good the tune is ?  But using any other tuner will void the 2 Year warranty
AND  I think that maintaining a 2 year warranty on a new designed motor is prudent

[Gadgetech]

With the current promotions from Fuel Moto, I think I'm going to give the Hi Rollers a shot.  I've had Rineharts on all my previous HDs but Jamie seems to be going the extra mile early on to get something that's EPA approved which probably doesn't make a difference outside of the US.  I will stick with an HD SEST for now (again due to warranty concerns) and HD intake.  I'm not sure about smoothness but others are reporting decent improvements for a Stage 1 upgrade on the M8. 

[Buffalo]

 I'm just curious here as to why you think in any way HD would honor any warranty on an engine with the exhaust modified by removing the cat? The only mod I've heard of as approved is the new street cannon mufflers, and they still use the cat!
Tuned by HD gear or not I believe your warranty to be invalid the moment you touch the cat! Using SEST tuner will not actually tune the bike, it will only use HD downloads for EPA standards, no where near what the engine would need if exhaust was extensively modded. jm2c fwiw Buffalo

[happyman]

With the current promotions from Fuel Moto, I think I'm going to give the Hi Rollers a shot.  I've had Rineharts on all my previous HDs but Jamie seems to be going the extra mile early on to get something that's EPA approved which probably doesn't make a difference outside of the US.  I will stick with an HD SEST for now (again due to warranty concerns) and HD intake.  I'm not sure about smoothness but others are reporting decent improvements for a Stage 1 upgrade on the M8.

may get by  the epa but  the warranty is gone

[saafrican]

Buffalo  and Happyman   you are right regarding removing the cat .
Harley have  prevented any modifications apart from SE kits by voiding the 2 year warranty ,

[Sunny Jim]

So if I flash the current tune from my ecu on to my PV and re flash it to the ecu but still run the current tune, my warranty is void. It's still the current tune with no mods. Why would it void the warranty.?

[hd06]

 Why would you want to do that.   

[Hossamania]

So if I flash the current tune from my ecu on to my PV and re flash it to the ecu but still run the current tune, my warranty is void. It's still the current tune with no mods. Why would it void the warranty.?

I think it would be void simply due to the use of a non HD tuner.

[Buffalo]

The current tune would be super lean with the cat removed!! And its already very lean from the factory to pass emissions. Can you say "hole in the pistons lean".
Removal of the cat will force you to retune with and aftermarket tuner to get the engine within its needed AFR's. All of this immediatelt voids any warranty, period.
Any mods not specifically ok'd by HD as being emissions compliant voids the warranty.
fwiw Buffalo

[PoorUB]

It always baffled my why HD would warranty a modified bike regardless who did it, dealer or some guy in his back yard. Seems to me that if the engine is modified, cams, exhaust or even just a simple tune the engine warranty would be void.

Can you buy a new pickup, slap a tuner on it and get warranty if the engine dies?

My understanding is HD is no longer honoring warranties unless it is done with the EPA approved kits.

[rbabos]

So if I flash the current tune from my ecu on to my PV and re flash it to the ecu but still run the current tune, my warranty is void. It's still the current tune with no mods. Why would it void the warranty.?

Non HD tuning product is reason enough.
Ron

[Sunny Jim]

In Australia , when you buy a new bike , you are offered a SE super tuner. I would have thought , regardless of the flash tuner, if your map is standard or equivalent to a stage 1 map ( copy and paste perhaps) , then surely that would be acceptable.
My understanding is that a super tuner is not available in the USA on M8 models,  but sold here.

[Glide17]

I wanted my bike to look standard so I've fitted a screaming eagle AC to my m8 ,
From a design point the std and SE filter elements are totally different . The SE is three times bigger .
How Harley could even  fit the std ridiculous filter is a sin ,it is so small .you will be horrified at the piece of crap .
The SE filter housing opening is huge compared to the std housing , the front doesn't have the rectrictive gauze , and the bottom of the housing is open .
The SE unit is suitable for the new 114 motor so will easily flow enough air for a modified 107 .

I wanted to install a stage 2 kit
But looking at the toque curves ,I've decided to only do stage 1
The M8 is geared to do 3500 rpm  @ 80mph
Max Torque for stage 1. 106.@3500rpm  Price $650
Max Torque for stage 2.  107@ 3500rpm. Price. $2500

At the moment (nov2016) there are no header pipes for the M8 , which should change those torque figures by flowing more air in an out ,
So I'm going to remove the cat converter .
But instead of cutting a flap in the collector box , I'm going to remove the right side muffler and try and remove the cat with a 3"?? Holesaw and a pry bar / scraper .
Failing that. I'll cut the header pipe on one of the existing collector welds , remove the cat and weld the pipes together again . Welding on top of a thick weld is easier that welding thin flat metal . And visually you shouldn't notice that the collector has been modified . Also be aware that the header pipes are made from stainless Steel , so you need to have the correct welder and wire .

With all those mods the bike has to be retuned .
To keep the warranty you have to re flash with a SE tuner .
I don't know how good the tune is ?  But using any other tuner will void the 2 Year warranty
AND  I think that maintaining a 2 year warranty on a new designed motor is prudent

The main difference between the torque cam is that it runs the torque curve out longer whereas the stock cam falls on its face after 3500rpm. If you never rev higher than 3500 not an issue

[Buffalo]

Harley stepped up and agreed to comply with the new Euro 4 Emission standards for all it '17 bikes. Only product manufactured by HD and approved to these standards will keep the warranty. Any mods to ignitions, or exhausts that do not comply VOID the warranty.
A modified exhaust (removal of the cat) will certainly require changes far beyond anything allowed under warranty. Same rule would apply to any Ecm other than approved HD with their downloads.
FWIW, I would do the Stage 1 (if you can't live with stock),ride out the warranty, then modify to your hearts content. The other choice to ignore warranty and modify now, never expecting HD to cover any part of the powertrain. Buffalo

[DTTJGlide]

ThunderMax is close to having one ready for the M8, although many don't care for them I would think it would be a good solution to keeping warranty on a mildly modified bike since it's a complete replacement for the original ecm. You should be able to replace all the stock parts, including the ecm since it was never tampered with I would think there would be no telltales to show that it had been modded. Thoughts?

[Hossamania]

I can't answer the question of whether they would know if it was replaced. I just think of how it's going to work if it breaks down on a ride and has to be towed in, are you going to carry the ecu with you and change it before the truck gets there?

[DTTJGlide]

  Nothings perfect

[jmorton10]

Who cares about a warranty LOL??

I have voided the warranty on every bike I owned 10 minutes after I brought it home HaHa

~John

[chamokie]

Who cares about a warranty LOL??

I have voided the warranty on every bike I owned 10 minutes after I brought it home HaHa

~John

I can see that on a tried and proven TC, but....the new engine is just that new, it needs to prove itself prior to putting on major mod's. Let HD pay for breakdowns. Once free of the mother's strings, go for it. keep us posted as how the eng takes the mod's.

[garsam]

I'm wondering why car engineering has evolved to the point where they are making huge hp with high flow after market cats when doing extensive mods, why aren't bike exhaust manufacturers able to do the same?  A 'friend' removed his cat by ramming a big honkin screw driver into it and then sucking out the pieces and then realizing it was magnetic (?) pulled out all the resulting debris with one of those extendable mags ya use for retrieving nuts etc. Afterwards it's clean and clear inside and is still stock on the outside😈