The future of the M8

[les]

So, just for the record, I'm not overly concerned about the smoking engines.  It'll be fixed.  I really like the M8...a lot!

Anyway, will we see a M8 version of the 120R and 120ST?  Or will there be a bigger displacement crate engine?  Will folks be doing a lot of Timken conversions?  I wonder if the SE (JIMS) Timken conversion tool works on the M8 left side casing.

(Maybe all of this is in the 2017 SE catalog and I've just not taken the time to read through.)

[Tattoo]

Hey les when you get done reading the 2017 SE catalog can you let us know about all the typo's ?

[les]

Hey les when you get done reading the 2017 SE catalog can you let us know about all the typo's ?

LOL!  Of course!

[HV]

From what Ive seen so far the Public have embraced the M8 very well...sales of the new bikes are very good ......the Big Bore kits are showing some interest but with the debate as to the usefulness of the new SE Tuners that's definitely a hold back ...the few Stage 1 kits are working well but there is not much tuning needed to accomplish that  ....I can see a lot of PV units being used for anything more then a Stage 1 as for the Smoking ...its a non issue .....It may have been a few early VIN #s deal or a bad batch but looks like its very limited or just plain internet Hype 

[Deye76]

Every time a new engine is brought to market a few have to bash it before it's had time and miles to prove itself. Guess they think it makes them sound tough. 

[hd06]

 Future looks good for M8 I love the torque of mine.

[BVHOG]

The future of the M8?   Aftermarket is already busy, individual rocker adjustment, new cam grinds, more exhausts than anyone would ever need. Aluminum throttle bodies. Custom pistons etc. Pretty much everything that was done to the twincam but once again starting from scratch.

[Piston Broke]

It looks like Harley's first "modern" Big Twin engine to me, which I'm not adverse to. Meaning that all covers and cases are starting to match up etc.

Are the mounting points, e.g. engine up front and swingarm back in the rear identical to older models?

I have not had a chance to look at the fiches to see if the frame is the same.

What have they done to the rear header ... tucked it in a little more?

How's ground clearance?

As an aisde, I was reading up on combustion chamber design and what I saw was that although 4 valve heads produced more power in the mid-range, where you'd want it on a tourer, at higher rpm, they actually lost out to 2 valves again.

Any opinions?

[Jako1]

IMO the TC is done
Once The MOCO redoes the Dyna chassis
I like my M8
My wife says NO more bikes 

[wfolarry]

I think you'll be seeing 124's & more from the MOCO. The bigger stud pattern will allow for big bores. The 4 valves can feed them. Just a matter of time but a couple years from now big bore baggers will be the norm. JMO.

[Rockout Rocker Products]

 I dunno. I've pondered the switch lately. Today I was sitting at a light, watching my left grip shake back & forth 1/2".... the urge for a M8 left me.

[Piston Broke]

I think you'll be seeing 124's & more from the MOCO. The bigger stud pattern will allow for big bores. The 4 valves can feed them. Just a matter of time but a couple years from now big bore baggers will be the norm. JMO.

Is 2,000cc going to become the new norm, or will we just need that to keep them performing at 80/80 ... 100/100 with increasing emissions restrictions?

Do we need "more bigger" forever or is it going to plateau at some point?

[PoorUB]

IMO the TC is done

Care to guess about the Evo or Shovel?

Of course the TC is done! HD would not have come out with the M8 if they were going to keep the TC around!

[Jako1]

Evo IMO was the better engine
I put lots of miles on 3 new ones
The best was the 92 FLHS
U know what happened to that bike
I had 58k trouble free miles on it when I sold it in 97 for a FLHT
Moved to a 88 TC  what a dog
I had shovels and a Pan
60 FL14001

[ocezam]

Moved to a 88 TC  what a dog

Hilarious!  Thanks!

Yeah by 21st century standards the Shovel, Pan and even the Evo were incredible engines....  Please!

I like history.  I rarely want to ride it.

[Deye76]

"The best was the 92 FLHS"

Those were great machines. I had a 1988, 90,000 trouble free miles when it was stolen.

[Tattoo]

"Yeah by 21st century standards the Shovel, Pan and even the Evo were incredible engines....  Please!

I like history.  I rarely want to ride it."


I can't wait to ride them 

[Jako1]

I can't wait to ride them 
Do it  do it     
I stopped in for a filter and look what followed me home on Labor Day 

[Tattoo]

I can't wait to ride them 
Do it  do it     
I stopped in for a filter and look what followed me home on Labor Day 

Oh I have rode several ,I was talking about the comment saying he rarely wanted to ride the old bikes.

[TorQuePimp]

Having ridden two of them

I think the "m" was for mistake

I hope s&s gets a 2 valve conversion quick

[Eccool]

Having ridden two of them

I think the "m" was for mistake

I hope s&s gets a 2 valve conversion quick

What didn't you like about them?  What is a two valve head supposed to fix?

[rbabos]

Interesting opposing opinions from knowledgeable members.
Ron

[hd06]

  There was talk before the M8 came out, What was Harley was going to do about compete with Victory and Indian. We have M8 that does the job I think its hard to except the new motor. EVO went through this as well Shovel. M8 here to stay.   

[TorQuePimp]

Having ridden two of them

I think the "m" was for mistake

I hope s&s gets a 2 valve conversion quick

What didn't you like about them?  What is a two valve head supposed to fix?

The rpm range our engines operate in is somewhat constricted to its basic design...that really has not changed

sticking a 4 valve head on top of a low tech twin isnt going to make it better....the opposite might be closer to the truth

Ill take a "we will see" attitude and when the heads start rolling in to be modified as always ill do what i do to the best of my ability.

  Harley isnt alone in the market anymore and eventually i see people moving in another direction....or keeping what they have

[Eccool]

The vast overwhelming majority of ride reviews of the M8 that I have seen have been positive.  That includes reviews from magazines and websites that get to ride bikes from all of the manufacturers.  From what I have seen, they have all indicated the M8 is a step forward, specifically in the areas of smoothness and power. 

As far as the four valve head having more or less potential than the two valve head:  A)  That remains to be seen  B)  Probably 90% of riders are going to be satisfied with either a stage one or two.  What the head can or cannot do would be a moot point.  Harley's fortunes might change for the worse, but it won't be because of the M8.

[PoorUB]

The vast overwhelming majority of ride reviews of the M8 that I have seen have been positive.  That includes reviews from magazines and websites that get to ride bikes from all of the manufacturers.  From what I have seen, they have all indicated the M8 is a step forward, specifically in the areas of smoothness and power. 

As far as the four valve head having more or less potential than the two valve head:  A)  That remains to be seen  B)  Probably 90% of riders are going to be satisfied with either a stage one or two.  What the head can or cannot do would be a moot point.  Harley's fortunes might change for the worse, but it won't be because of the M8.

Magazine articles are generally biased. Keep in mind how a magazine makes money, and realize that it is not from subscription fees. Are you going to write up a negative article about HD if they spend several thousand dollars a year in advertising? I can not remember ever reading a negative article in any magazine. Even their motorcycle comparisons are poor as they rarely pick one bike over the other, and when they do, they concede that second place was not far behind and is a very good choice too.

As for the M8, IMO, it is just more of the same from HD. Seriously, the bottom end has very little changes as to the type of manufacture. Guys have been bitching about pressed together cranks for years, the M8? Still has a pressed crank and it is better than a TC? Still the same lousy lifters guys have been complaining about for the last ~5 years. About the only thing improved it the way the rocker arm shaft is retained, and many of us are still trying to figure out how to maintain valve lash with no adjustment on the rocker arms. Four valve heads on an engine that barely turns over 5,000 RPM?? Give me a forged one piece crank, automotive style con rods with caps, plain bearings with full pressure lube, and full water cooling then I might get excited.

The M8 is probably a good engine, I just don't see it as being a great engine, nothing to get really excited over. I bought a new Limited in July because I did not want an M8, at least not yet.

[HV]

Give me a forged one piece crank, automotive style con rods with caps, plain bearings with full pressure lube, and full water cooling then I might get excited.


They had one...called the V Rod ...not made any more due to lack of sales 

[PoorUB]

Give me a forged one piece crank, automotive style con rods with caps, plain bearings with full pressure lube, and full water cooling then I might get excited.


They had one...called the V Rod ...not made any more due to lack of sales 

They put it in the wrong motorcycle frame!

[HV]

Yup they did 

[RXBOB]

Took my new M8 RG ( SE Mufflers, high flow A/C) out for its first real test yesterday, did over 700ks for the day in 30*C weather on some pretty long straight, twisty and in interrupted roads. 140km/hr, cruise control, Tunes, GPS.

Well I was pretty impressed the suspension worked it cornered well, fuel economy was excellent, clutch is a dream and has plenty of power and torque for what it is ( an external push rod engine).

Checked my engine oil level at all stops and at home no movement on the dipstick.

So all in all this has to be the best thing Harley has done, I remember all the bagging of the Twin Cam when that took over from the Evo this is all just the same sorta stuff

I am I happy I got one,,,,,,,,,,,,,,,,HELL YEAH

[hd06]

Congratulations  on your new ride they are smooth torqu running machines, I'm impressed with mine.

[FSG]

Took my new M8 RG ............................. 

Sometimes I hate people just because       but in this case I'm just jealous.       ride on   

[mobe]

[/quote]

They put it in the wrong motorcycle
[/quote]

Amen brother, amen.

[Admiral Akbar]

I hope s&s gets a 2 valve conversion quick

You should explain this.. Maybe put the T back in HTT??

[TorQuePimp]

I hope s&s gets a 2 valve conversion quick

You should explain this.. Maybe put the T back in HTT??

Scroll back already did

[Admiral Akbar]

I hope s&s gets a 2 valve conversion quick

You should explain this.. Maybe put the T back in HTT??

Scroll back already did

So that's your tech answer?  OK...

[Templer]

Think the M-8 is the next step. My question is WHO is going to shack up my rattle cans?? 

[1FSTRK]

Time will tell what kind of job Harley did with their 4 valve heads. The 4 valve per cylinder concept on a Harley is not new nor was it a leap forward but it was certainly not a step backwards either. I have seen several that went through Vic's shop on EVO engines and one that was converted to run on a Twin cam and they were all respectable back in the day. Now days with dual plugs, EFI and some other modern advances these M8 engines should be even better as long as HD did not make some unforeseen error in their design.

The grandfather of the single cam, 4 valve head, Harley engine was the Fueling/Quantum head on an Evo and here is an example of what they could do back in the day with a little effort.
113ci S&S cases, cylinders, pistons
4 Valve heads
W-6 Cam
S&S carb Force/K&N air cleaner
Custom pipe with Hooker muffler

[jmorton10]

There is nothing really new or revolutionary about 4 valve Harley heads.

http://thekneeslider.com/4-valve-hemi-heads-for-harley-big-twin-engines/

We built a few motors with the Fueling 4 valve heads years ago.  If they where dramatically better you would see them everywhere (I haven't seen a set in years)

~John

[HD/Wrench]

at some point I hope they dump the stupid cam set up and go over head. Now we can start making better changes. The ability to control intake and ex separately  has been one of the largest improvements in over head cam engines . HD is holding onto the past. If you want power like others then well take a long hard look at what they are doing how and freaking successful it has been. IE victory those engines have very little failures and make big power 110/110 with a cam swap and slip on mufflers. Engines are smooth with very wide bands of usable power. I feel you are seeing a intermediate engine myself.

Look at what the new EPA is looking for, ( noise is also in the EPA ) The regs keep getting stiffer. The dual over head cams would be of huge help . I do not think we will see a "vanos" system anytime soon. That would be great but packaging  is a nightmare.  And HD is anything but up for spending huge money. "more so just enough to almost get the job done"

[harleytuner]

at some point I hope they dump the stupid cam set up and go over head. Now we can start making better changes. The ability to control intake and ex separately  has been one of the largest improvements in over head cam engines . HD is holding onto the past. If you want power like others then well take a long hard look at what they are doing how and freaking successful it has been. IE victory those engines have very little failures and make big power 110/110 with a cam swap and slip on mufflers. Engines are smooth with very wide bands of usable power. I feel you are seeing a intermediate engine myself.

Look at what the new EPA is looking for, ( noise is also in the EPA ) The regs keep getting stiffer. The dual over head cams would be of huge help . I do not think we will see a "vanos" system anytime soon. That would be great but packaging  is a nightmare.  And HD is anything but up for spending huge money. "more so just enough to almost get the job done"

I agree but I would imagine it's a fine line for HD to walk, trying to become "modern" but keep the traditionalists happy.  We tend to demand more but don't want change to get it.

A very good friend of mine bought a bar that had been out of business for about 5 years.  When he got it opened up all the old regulars started coming in.  They soon started trying to run the new younger croud out. (the old timers didn't want the change, they wanted to hang out and play cards like they used to, without the jukebox blaring anything other than AC/DC.  I told Scott he better put an end to it quick, there's a reason it went out of business in the first place.  The old timer customers didn't spend enough to keep the place in business. 

[Durwood]

I personally like the M8 platform and feel it has a bright future in our industry.

George Bryce at Star racing posted some flow sheets on Facebook of M8 heads with minor port work and valve job that are eclipsing a fully ported 110 head.

We as humans are creatures of habit and typically don't like change, but IMO, this new mill will prove to be a winner for all in the business.

Everyone have a very Merry Christmas.

[Don D]

I like them, have great hope for the future

[1FSTRK]

I personally like the M8 platform and feel it has a bright future in our industry.

George Bryce at Star racing posted some flow sheets on Facebook of M8 heads with minor port work and valve job that are eclipsing a fully ported 110 head.

We as humans are creatures of habit and typically don't like change, but IMO, this new mill will prove to be a winner for all in the business.

Everyone have a very Merry Christmas.

I just saw some flow numbers from testing with prototype valves and port work that look like these heads will deliver great power and torque. No dyno number yet but once proper cams and TBs are added to the mix things should get very interesting.

[rigidthumper]

He showed 325/235 @ 1/2" lift stock, 343/255 @ 1/2" lift after port & valve work. Heads less of a restriction than the past...

[Jonny Cash]

Future looks bright to me for these engines. Axtell released their kit to take the 107's to 117, and suburban is showing a 120 piston and cylinder drop on kit.  Looks like parts development has been pretty quick.  Bryce,s initial port work looks really  promising.  Looks like big cubes on these is going to be a pretty easy deal.

[1FSTRK]

Big cubes will be a must with ports and valves this big in the M8. After finally growing the twin cam big enough to use it's ports they appear to have gone back to their old math for the port and valve sizes for the 107ci M8.

[PoorUB]

Like the M8? I guess I don't dislike it, I suppose I like it, but I like the Twin Cam too. I just don't see the M8 as much different that the TC,  remove one cam, add four valve heads to a TC. The engineering of the M8 screams TC variant ot me. It is all the same engineering in a slightly different package.

[Smarty]

Isn't that exactly what we love about the small block chevy? Variations but true to its roots.


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[Ohio HD]

at some point I hope they dump the stupid cam set up and go over head. Now we can start making better changes. The ability to control intake and ex separately  has been one of the largest improvements in over head cam engines . HD is holding onto the past. If you want power like others then well take a long hard look at what they are doing how and freaking successful it has been. IE victory those engines have very little failures and make big power 110/110 with a cam swap and slip on mufflers. Engines are smooth with very wide bands of usable power. I feel you are seeing a intermediate engine myself.

Look at what the new EPA is looking for, ( noise is also in the EPA ) The regs keep getting stiffer. The dual over head cams would be of huge help . I do not think we will see a "vanos" system anytime soon. That would be great but packaging  is a nightmare.  And HD is anything but up for spending huge money. "more so just enough to almost get the job done"

If HD could make a compact version of the 4 cam sportster valve train, we can have the separate intake from exhaust and keep the OHV with push rods. And I mean that for tradition sake. I think going OHV OHC might be a negative to HD owners. The V-Rod was enough change that it just didn't sell. 

[Durwood]

Big cubes will be a must with ports and valves this big in the M8. After finally growing the twin cam big enough to use it's ports they appear to have gone back to their old math for the port and valve sizes for the 107ci M8.

The M8 as a stage 2 will be plenty for 90% of Harley performance enthusiasts IMO, some guys will be happy with a set of pipes and good tune.

The all in big cube crowd will be able to make serious power without breaking the bank on extensive head work.

[Hossamania]

at some point I hope they dump the stupid cam set up and go over head. Now we can start making better changes. The ability to control intake and ex separately  has been one of the largest improvements in over head cam engines . HD is holding onto the past. If you want power like others then well take a long hard look at what they are doing how and freaking successful it has been. IE victory those engines have very little failures and make big power 110/110 with a cam swap and slip on mufflers. Engines are smooth with very wide bands of usable power. I feel you are seeing a intermediate engine myself.

Look at what the new EPA is looking for, ( noise is also in the EPA ) The regs keep getting stiffer. The dual over head cams would be of huge help . I do not think we will see a "vanos" system anytime soon. That would be great but packaging  is a nightmare.  And HD is anything but up for spending huge money. "more so just enough to almost get the job done"

If HD could make a compact version of the 4 cam sportster valve train, we can have the separate intake from exhaust and keep the OHV with push rods. And I mean that for tradition sake. I think going OHV might be a negative to HD owners. The V-Rod was enough change that it just didn't sell.

I think the Vrod didn't sell because it was not a very attractive package.

[1FSTRK]

Big cubes will be a must with ports and valves this big in the M8. After finally growing the twin cam big enough to use it's ports they appear to have gone back to their old math for the port and valve sizes for the 107ci M8.

The M8 as a stage 2 will be plenty for 90% of Harley performance enthusiasts IMO, some guys will be happy with a set of pipes and good tune.

I agree here, I just do not think the stage 2 will be showing a great increase in hp/ci over a stage two Twin Cam.

The all in big cube crowd will be able to make serious power without breaking the bank on extensive head work.

I guess here is where we wait and see. Time will tell if the M-8 heads with their large ports and valves can turn large flow numbers into serious HP/CI on even large displacement engines. With flow numbers like  "325/235 @ 1/2" lift" for stock M-8 heads they are flowing as good or better then most ported Twin cam heads so a stock head M-8 with good cams should be making power more comparable to a Twin cam 107ci kit with ported heads and cams.

The single cam part does little for me from a performance stand point. The real change is the intake/exhaust tract and HP/CI over the rpm range will be the tell on how much of an improvement there will be.

[HD/Wrench]

well we have Axtell selling 4.125 pistons and stating bore the stock 107 to that point. Not to make fun but really ?? Brand new part and we know that there could be little to no real testing at this point so early in the game..  Maybe it works out or maybe it does not.. but to me that overly optimistic currently .. I guess we wait for the first dozen guinea pigs to see how it does .

If it works out that is great , simply way to get to 117 inch.

[1FSTRK]

well we have Axtell selling 4.125 pistons and stating bore the stock 107 to that point. Not to make fun but really ?? Brand new part and we know that there could be little to no real testing at this point so early in the game..  Maybe it works out or maybe it does not.. but to me that overly optimistic currently .. I guess we wait for the first dozen guinea pigs to see how it does .

If it works out that is great , simply way to get to 117 inch.

If indeed they checked liner thickness and found it to be comparable to other such practices it is reasonable to conclude it would work. The first 883s were bored to 1200s before the factory even released the 1100s. It  did not take long for the factory to follow and the 1200 is now the longest running cylinder the factory produces.

[Durwood]

Big cubes will be a must with ports and valves this big in the M8. After finally growing the twin cam big enough to use it's ports they appear to have gone back to their old math for the port and valve sizes for the 107ci M8.

The M8 as a stage 2 will be plenty for 90% of Harley performance enthusiasts IMO, some guys will be happy with a set of pipes and good tune.

I agree here, I just do not think the stage 2 will be showing a great increase in hp/ci over a stage two Twin Cam.

The all in big cube crowd will be able to make serious power without breaking the bank on extensive head work.

I guess here is where we wait and see. Time will tell if the M-8 heads with their large ports and valves can turn large flow numbers into serious HP/CI on even large displacement engines. With flow numbers like  "325/235 @ 1/2" lift" for stock M-8 heads they are flowing as good or better then most ported Twin cam heads so a stock head M-8 with good cams should be making power more comparable to a Twin cam 107ci kit with ported heads and cams.

The single cam part does little for me from a performance stand point. The real change is the intake/exhaust tract and HP/CI over the rpm range will be the tell on how much of an improvement there will be.

As product development continues I can see these 107's easily making comparable TQ/HP to a Twin cam with the added compression and appropriate camshaft profile.

[rbabos]

at some point I hope they dump the stupid cam set up and go over head. Now we can start making better changes. The ability to control intake and ex separately  has been one of the largest improvements in over head cam engines . HD is holding onto the past. If you want power like others then well take a long hard look at what they are doing how and freaking successful it has been. IE victory those engines have very little failures and make big power 110/110 with a cam swap and slip on mufflers. Engines are smooth with very wide bands of usable power. I feel you are seeing a intermediate engine myself.

Look at what the new EPA is looking for, ( noise is also in the EPA ) The regs keep getting stiffer. The dual over head cams would be of huge help . I do not think we will see a "vanos" system anytime soon. That would be great but packaging  is a nightmare.  And HD is anything but up for spending huge money. "more so just enough to almost get the job done"

If HD could make a compact version of the 4 cam sportster valve train, we can have the separate intake from exhaust and keep the OHV with push rods. And I mean that for tradition sake. I think going OHV might be a negative to HD owners. The V-Rod was enough change that it just didn't sell.

I think the Vrod didn't sell because it was not a very attractive package.

You calling my bike ugly. Actually what killed the vrod from the start was price and accessory support. Take a look at the Victory Octane. Almost a direct copy of the v rod but 5k less and already more accessories available.  They are selling. Piss poor marketing on HDs part when it came to the rod. It's almost like they never really wanted to sell them from the get go based on price alone, then followed up with next to no decent accessories. Basically a no brainer for that level of bike. Pay 17+k for a vrod that runs like "Potty mouth" on factory cal or 12k for the Octane that runs extremely nice on the factory cal that looks about the same, good quality and USA made. The equivilent HD Street is a joke in comparison. Another dud in my view.
Ron

[1FSTRK]

Big cubes will be a must with ports and valves this big in the M8. After finally growing the twin cam big enough to use it's ports they appear to have gone back to their old math for the port and valve sizes for the 107ci M8.

The M8 as a stage 2 will be plenty for 90% of Harley performance enthusiasts IMO, some guys will be happy with a set of pipes and good tune.

I agree here, I just do not think the stage 2 will be showing a great increase in hp/ci over a stage two Twin Cam.

The all in big cube crowd will be able to make serious power without breaking the bank on extensive head work.

I guess here is where we wait and see. Time will tell if the M-8 heads with their large ports and valves can turn large flow numbers into serious HP/CI on even large displacement engines. With flow numbers like  "325/235 @ 1/2" lift" for stock M-8 heads they are flowing as good or better then most ported Twin cam heads so a stock head M-8 with good cams should be making power more comparable to a Twin cam 107ci kit with ported heads and cams.

The single cam part does little for me from a performance stand point. The real change is the intake/exhaust tract and HP/CI over the rpm range will be the tell on how much of an improvement there will be.

As product development continues I can see these 107's easily making comparable TQ/HP to a Twin cam with the added compression and appropriate camshaft profile.

Taking a look at the stage 2 builds that are showing up in the dyno section and considering the higher compression the M-8 starts with you may start to see comparable but that does say that the new design does not excel in the hp/cfm department. From a discussion of design point of view I would think if the head were better because of the additional flow alone the dyno numbers would be far more impressive.   

[XL90R]

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[XL90R]

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[XL90R]

Plenty of good stuff going on with these new motors and twin cam guys are gonna be pretty sad when they realize the potential these motors have..
And the power delivery is much much better.. I have never been a fan of twin cam Motors, I think this was the right step forward for Harley, they will never be able to sell a dohc water cooled motor.. this is the best base line motor to work with yet IMO..


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[joe_lyons]

[1FSTRK]

Now you are getting closer to using the area of the ports and valves.

[XL90R]

Big cubes will be a must with ports and valves this big in the M8. After finally growing the twin cam big enough to use it's ports they appear to have gone back to their old math for the port and valve sizes for the 107ci M8.

The M8 as a stage 2 will be plenty for 90% of Harley performance enthusiasts IMO, some guys will be happy with a set of pipes and good tune.

I agree here, I just do not think the stage 2 will be showing a great increase in hp/ci over a stage two Twin Cam.

The all in big cube crowd will be able to make serious power without breaking the bank on extensive head work.

I guess here is where we wait and see. Time will tell if the M-8 heads with their large ports and valves can turn large flow numbers into serious HP/CI on even large displacement engines. With flow numbers like  "325/235 @ 1/2" lift" for stock M-8 heads they are flowing as good or better then most ported Twin cam heads so a stock head M-8 with good cams should be making power more comparable to a Twin cam 107ci kit with ported heads and cams.

The single cam part does little for me from a performance stand point. The real change is the intake/exhaust tract and HP/CI over the rpm range will be the tell on how much of an improvement there will be.

As product development continues I can see these 107's easily making comparable TQ/HP to a Twin cam with the added compression and appropriate camshaft profile.

Here is a comparison of a bone stock 107 vs a 107 with SE hp cam and slip ons with no tuning.

This is the M8 with bassani 2:1, high flow filter and a power vision dyno tune..(85hp 110 tq) Throw a hp cam in and hp jumps to mid 90s. I'd say it's quite a bit better.






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[XL90R]

110tq @ 2700 rpms.. Now that's a good time

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[1FSTRK]

110tq @ 2700 rpms.. Now that's a good time

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First I would like to welcome you to HTT.

I do not think anyone is saying the M-8 does not run well in stock form or even that it does not benefit nicely from a stage two and a good tune. I am looking at the thread title from a performance/tech point of view.
In the Harley world it has always been a simple task to gain power by having the heads ported because they lacked adequate flow to feed the stock displacement from the factory. The M-8 comes with heads that have flow numbers that surpass those of most ported twin cam heads on the market. My point is speaking from a flow numbers or HP/CFM standpoint, if the head design is as good as the flow numbers a properly setup M-8 with cams and stock heads should be out performing the ported Twin Cam kits or these heads are not really an improvement. Another thing to look at will be what happens to the power when people hog out the ports to get even bigger flow numbers. Yes the power will go up but will they give up tq in the lower rpm range, will the power go up proportionally to the flow increase? If you look in the dyno section here you will see the M-8 graphs posted to date do not accurately reflect the amount of air these stock heads flow even when the bigger bore kits are added.

I am thinking the future will show that larger TB's will help to get hp/ci numbers as well as hp/cfm numbers closer to the level of the ported Evo and Twin cam designs but as I said above it will take more to show a legitimate improvement of the 4 valve head over the 2 valve heads and call the job HD did on these a success.

[XL90R]

110tq @ 2700 rpms.. Now that's a good time

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First I would like to welcome you to HTT.

I do not think anyone is saying the M-8 does not run well in stock form or even that it does not benefit nicely from a stage two and a good tune. I am looking at the thread title from a performance/tech point of view.
In the Harley world it has always been a simple task to gain power by having the heads ported because they lacked adequate flow to feed the stock displacement from the factory. The M-8 comes with heads that have flow numbers that surpass those of most ported twin cam heads on the market. My point is speaking from a flow numbers or HP/CFM standpoint, if the head design is as good as the flow numbers a properly setup M-8 with cams and stock heads should be out performing the ported Twin Cam kits or these heads are not really an improvement. Another thing to look at will be what happens to the power when people hog out the ports to get even bigger flow numbers. Yes the power will go up but will they give up tq in the lower rpm range, will the power go up proportionally to the flow increase? If you look in the dyno section here you will see the M-8 graphs posted to date do not accurately reflect the amount of air these stock heads flow even when the bigger bore kits are added.

I am thinking the future will show that larger TB's will help to get hp/ci numbers as well as hp/cfm numbers closer to the level of the ported Evo and Twin cam designs but as I said above it will take more to show a legitimate improvement of the 4 valve head over the 2 valve heads and call the job HD did on these a success.

I understand ya, and as someone Stated earlier in post I think the m8 how it stands will be satisfying for most the "typical" Harley riders.. For us other 10%
Nothing Harley sells in their motors stays stock anyhow.. Hell my 90" sportster puts out about the same power and very close tq to a built Twinkie 107.. I think given some time this new motor with the right internals will perform very well.. In its stock form it's" good enough" to appease the avg rider, and be a much more enjoyable ride over the TC.. I'm more hoping this new motor won't have all the same weak points the TC motor has in design.. Guess time will tell.
Thanks for the welcome btw!!


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[joe_lyons]

I hope that there is more than 10% out there.

[XL90R]

I hope that there is more than 10% out there.

Probably are, but that other % probably running SE internals lol.


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[HD/Wrench]

well we have Axtell selling 4.125 pistons and stating bore the stock 107 to that point. Not to make fun but really ?? Brand new part and we know that there could be little to no real testing at this point so early in the game..  Maybe it works out or maybe it does not.. but to me that overly optimistic currently .. I guess we wait for the first dozen guinea pigs to see how it does .

If it works out that is great , simply way to get to 117 inch.

I do not disagree, however until you get a fair amount of them out there and real miles on them.. When we did our first 98 inch kit due to failure with the Rev product. we had 5 of them running for close to 10 months before we released the kits and it did require a piston swap due to a ring issue. Now we where told that would not work. I understand that you can measure something and say well its been done before. but each new step in my opinion requires testing.  What testing has been done yet??

for that fact we still have no idea what we are in for as far as crank failures, new oil pump failures, rocker arm issues .. Not bashing it just stating I think that the view point needs to be widened a fair amount. No real miles on them yet and I rode with one to AK and it had some issues oil usage wise. They did repair it,  with a new engine.  He only has 1500 miles on the new one and thus far not using oil like the first one. But we all know all things can fail. 

as for the future of the M8 It will see some more changes without a doubt. Not sure I will ever own one but then again I am waiting on the new BMW bagger 

If indeed they checked liner thickness and found it to be comparable to other such practices it is reasonable to conclude it would work. The first 883s were bored to 1200s before the factory even released the 1100s. It  did not take long for the factory to follow and the 1200 is now the longest running cylinder the factory produces.

[Don D]

The larger head bolt pattern opens up possibilities. Maybe a 3/8 stroke 124? The heads have the overhead to go big. Valve control at higher rpm seems possible but testing will reveal more. We have given the 107 TC all  the head it can use and more and the results are well documented. Now we have new possibilities. If these motors will remain stable at 7-7500 rpm (~5500fpm) in a street configuration that is real exciting to me. Strong light pistons will extend the life.
Lots to look forward to.

[1FSTRK]

The larger head bolt pattern opens up possibilities. Maybe a 3/8 stroke 124? The heads have the overhead to go big. Valve control at higher rpm seems possible but testing will reveal more. We have given the 107 TC all  the head it can use and more and the results are well documented. Now we have new possibilities. If these motors will remain stable at 7-7500 rpm (~5500fpm) in a street configuration that is real exciting to me. Strong light pistons will extend the life.
Lots to look forward to.

Could you explain why?

[Don D]

Not really because I have not had a set of these heads in my hands yet.
It would depend on components weight, spring pressure required to get the job done, and perhaps less aggressive cam profiles could be employed. Spintron testing.

We are pushing the TC lifters now with the heavy components and spring pressures plus aggressive cam profiles.
What are your ideas relating to this?

[1FSTRK]

More valve weight, more retainer/keeper weight, more rocker weight (particularly away from center where it counts the most), more valve to guide surface area, and still running pushrods. I agree that flow will be achieved at lower lifts but without doing the math as you say, it seems a wash to me. It may show slightly better numbers in the math but I definitely would go as far as to say no appreciable gains through higher rpm due to valve train advancements.


 

[Don D]

I see your point, I may have been overly optimistic. Thanks

[PoorUB]

I ride with a group of guys that most of them run their HD's stock, right down to the exhaust. IMO, there probably more riders that leave them stock then mod them. I did big bore kits on my last two, but my 2016 I most likely will leave alone as I am fairly satisfied with the stock performance. I would not mind a bit more, but it is not as bad as my '05 or my '10 was. If I had an M8 I probably would leave it alone too as the stock performance is decent. That said I would still like to see 110 HP/120 torque at the rear tire.

[rigidthumper]

I ride with a group of guys that most of them run their HD's stock, right down to the exhaust. IMO, there probably more riders that leave them stock then mod them. I did big bore kits on my last two, but my 2016 I most likely will leave alone as I am fairly satisfied with the stock performance. I would not mind a bit more, but it is not as bad as my '05 or my '10 was. If I had an M8 I probably would leave it alone too as the stock performance is decent. That said I would still like to see 110 HP/120 torque at the rear tire.

Simple as buying an M8 107, adding the 114 stage 3 kit, and tune it. Easy to do- just spend $, and its covered by warranty.

[Sunny Jim]

All I know is that my M8 gearbox whines like a mother in law! It is NOISY . Harley dealer says that's normal. Normal my ass!!! I didn't spend $36000.00 for a whining 6 speed. My previous FLLh 's were no where near this.

[rbabos]

All I know is that my M8 gearbox whines like a mother in law! It is NOISY . Harley dealer says that's normal. Normal my ass!!! I didn't spend $36000.00 for a whining 6 speed. My previous FLLh 's were no where near this.

Are there any other bikes in your area that sound the same or just yours? That would establish normal. I believe that's the first word service people learn and use it a lot. Quite often accompanied with they all do that.
Ron

[hd06]

 Mine don't

[PoorUB]

I ride with a group of guys that most of them run their HD's stock, right down to the exhaust. IMO, there probably more riders that leave them stock then mod them. I did big bore kits on my last two, but my 2016 I most likely will leave alone as I am fairly satisfied with the stock performance. I would not mind a bit more, but it is not as bad as my '05 or my '10 was. If I had an M8 I probably would leave it alone too as the stock performance is decent. That said I would still like to see 110 HP/120 torque at the rear tire.

Simple as buying an M8 107, adding the 114 stage 3 kit, and tune it. Easy to do- just spend $, and its covered by warranty.

Give it to me in a stock bike, right out of the factory, so it does not need to be tore apart to get there.

[Hossamania]

I ride with a group of guys that most of them run their HD's stock, right down to the exhaust. IMO, there probably more riders that leave them stock then mod them. I did big bore kits on my last two, but my 2016 I most likely will leave alone as I am fairly satisfied with the stock performance. I would not mind a bit more, but it is not as bad as my '05 or my '10 was. If I had an M8 I probably would leave it alone too as the stock performance is decent. That said I would still like to see 110 HP/120 torque at the rear tire.

Simple as buying an M8 107, adding the 114 stage 3 kit, and tune it. Easy to do- just spend $, and its covered by warranty.

Give it to me in a stock bike, right out of the factory, so it does not need to be tore apart to get there.

I agree, why can't we just buy a Harley that has enough power? (Of course, there is no such thing as enough power.)

[rbabos]

I ride with a group of guys that most of them run their HD's stock, right down to the exhaust. IMO, there probably more riders that leave them stock then mod them. I did big bore kits on my last two, but my 2016 I most likely will leave alone as I am fairly satisfied with the stock performance. I would not mind a bit more, but it is not as bad as my '05 or my '10 was. If I had an M8 I probably would leave it alone too as the stock performance is decent. That said I would still like to see 110 HP/120 torque at the rear tire.

Simple as buying an M8 107, adding the 114 stage 3 kit, and tune it. Easy to do- just spend $, and its covered by warranty.

Give it to me in a stock bike, right out of the factory, so it does not need to be tore apart to get there.

Plenty of them out there, just not this brand.
Ron

[HD/Wrench]

I ride with a group of guys that most of them run their HD's stock, right down to the exhaust. IMO, there probably more riders that leave them stock then mod them. I did big bore kits on my last two, but my 2016 I most likely will leave alone as I am fairly satisfied with the stock performance. I would not mind a bit more, but it is not as bad as my '05 or my '10 was. If I had an M8 I probably would leave it alone too as the stock performance is decent. That said I would still like to see 110 HP/120 torque at the rear tire.

maybe that is the point. I love my HD and will not be without one. However my next bike will most likely be the new BMW bagger. Simple reason 160 hp ( yes at the crank) smooth killer everything. from brakes to controls, heated items stereo nav system.  HD is the only one with the massive add on , fix make it better 100 times over.

Will the BMW be for everyone nope but the cool thing will be its my money.. HA HA I want big power almost no ex noise .    I like to ride long distance in comfort. Being I tune all makes of bikes I get exposed to much more than most . I am here to say most knock them but never ridden them. Today there is a large % of customers than own a HD as well as something else. Main thing I hear the HD bagger is my local bike a few hours tops  but for long trips I take my "X" bike.  Hell look at the little octane 100 Hp with air clean and slip on.. Lets see HD pull that off in a 1250 cc bike.   as well I do not think that many care " how the engine looks per say" they want a HD and thats it.. I know many say they will not go the route of the others HA HA yea wait and see. IF they want to keep the stock rising they need to sell more bikes. and the stock price is all HD has cared about in a long time..   IF they can market it it will sell over head cam liquid cool.. hell you might see a new Eco badge on one.. HA HA


Simple as buying an M8 107, adding the 114 stage 3 kit, and tune it. Easy to do- just spend $, and its covered by warranty.

Give it to me in a stock bike, right out of the factory, so it does not need to be tore apart to get there.

[Hossamania]

GMR, I'm with you. I haven't ridden a bunch of different models, but I have ridden a BMW for an extended period, though not the bagger. Beautiful riding bikes, not beautiful bikes though. But lots of power and real handling.
I met a rider years ago who was on a two week trip, riding a Beemer sport touring rig. Said he did the same ride last year on an HD. The HD made his butt sore after a few hours. The BMW made his knees sore after a few hours.
I may have to sit on the 1600 GT to see how the pegs feel. The R1200RT was tough on the knees.
I will say that my Ultra is pretty comfortable on long rides. Needs more power, though it is not horrible. Better looking than any Beemer, by far.

[FSG]

I agree, why can't we just buy a Harley that has enough power? (Of course, there is no such thing as enough power.)

Because we all want more than enough.   

[Hossamania]

I agree, why can't we just buy a Harley that has enough power? (Of course, there is no such thing as enough power.)

Because we all want more than enough.   

We need just enough to beat our friends. Well, you're right, maybe not just enough, more than enough.

[Hossamania]

Looking forward to taking an M8 for a ride.

[Don D]

I wonder if the case will bore  4.5 x 1.3 and if so is there still gasket seal

[DTTJGlide]

The Suburban Speed Mahle pistons are 4.185 & their 120 kit is listed for $998.84, the cylinders appear to be stock HD. I don't see how anyone could produce new non HD cylinders that quickly or at that cost, so at least the SE cylinders can be bored that far. I also think with the reputation that they have they feel confident that this setup will work. At the price that the SE cylinders are I would be surprised if they start out differently than the stock cylinders, since they all fit in the same case bore. It will be interesting to see some measurements on the stock vs SE cylinders, hopefully Tattoo or another dealer rep can give us some insight on this. So far it seems as if a big cube M8 is going to be quite reasonable cost wise. By the way a 4.185x4.5 equals a 124.

[tomcat64]

All I know is that my M8 gearbox whines like a mother in law! It is NOISY . Harley dealer says that's normal. Normal my ass!!! I didn't spend $36000.00 for a whining 6 speed. My previous FLLh 's were no where near this.

have your dealer check the date code on the cam shaft.. one of ours did the same thing, I thought it was the counter balancer, but it turns out that Harley must have gotten some bad cams from a vendor.. when we called tech services with the cam code they sent out a new cam shaft over night!

[trex]

I wonder if the case will bore  4.5 x 1.3 and if so is there still gasket seal

Compare gasket area on an M8 to a TwinCam, The M8 is huge

[Ohio HD]

I wonder if the case will bore  4.5 x 1.3 and if so is there still gasket seal

Compare gasket area on an M8 to a TwinCam, The M8 is huge

What about the cylinder head gasket surface? I would think it has stayed the same as the Twin Cam.

[trex]

I wonder if the case will bore  4.5 x 1.3 and if so is there still gasket seal

Compare gasket area on an M8 to a TwinCam, The M8 is huge

What about the cylinder head gasket surface? I would think it has stayed the same as the Twin Cam.

That wouldn't make any sense

[rigidthumper]

If it'd fit, I'd like to try a 4 3/8" square motor.

[trex]

Me too. When I added the M8 picture of the head I wasn't allowed to send 2 pictures to compare. Here is TwinCam head for comparison. The M8 gasket area is MUCH larger

[Don D]

Square, you betcha, aftermarket cyls.
The perimeter squish would enhance swirl too.

[rigidthumper]

I love the potential for square engines

[rbabos]

I love the potential for square engines

Me too. I went a step further with over square.
Ron

[N-gin]

I would like to see the crank handle these big inch combos and the balancer for high RPM. I can see the balancer being lightened and even done away with when getting the crank done and balanced.
Personally I think it's nice that Harley tried one more time to keep up and stay the same image. Seems to put out some nice numbers, however it still at peak at highway speeds wich means as you give it throttle you still loose torque the more you twist the engine. Down shifting still inevitable.
I do like the lighter valve train components, but would like to see more to the right torque.

I know for a fact I can stay I'm my 6 gear at 65 mph and no down shifting and I can walk a Valkury that down shifted. But my peak torque is at 4400 and I'm at 2800 at 65. This is with my crappy 107 TC, 2 valve, air cooled ticking sewing machine.
I guess I'm just a right side torque kind of person.

As for the V-rod I never cared for the look, but my friend likes his so different strokes for different folks. I have yet to see a that Victory on the street, but I've seen a few V-rods.

[NCTURBOS]

Will the 4.500" stroke be the standard on the '18 models? Thought I had seen/heard that somewhere but can't find it...

TIA,

K.

[jmorton10]

A very good friend of mine bought a bar that had been out of business for about 5 years.  When he got it opened up all the old regulars started coming in.  They soon started trying to run the new younger croud out. (the old timers didn't want the change, they wanted to hang out and play cards like they used to, without the jukebox blaring anything other than AC/DC.  I told Scott he better put an end to it quick, there's a reason it went out of business in the first place.  The old timer customers didn't spend enough to keep the place in business.

I ran a biker bar for over 20 years & we welcomed everybody.  My partner was H.A. & it wasn't unusual to have 10 Harleys out front.  Inside however, you would find patch holders drinking right along with a crew of business men in suits from a huge business down the street from us.

Everybody got along just fine.  We also made sure nobody got out of line, but that wasn't to hard with who we had watching our back LOL.

~John