Harley Busted by EPA for Screaming Eagle Tuners

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2012-Honda-ST1300-vs-Kawasaki-Concours-14-vs-2013-Yamaha-FJR1300A-hp-torque-dyno.jpg


The above dyno plots are quite interesting. Even though the Kakasucky Concours has a ~100cc displacement advantage, the FJR has more torque over the 2200 - 4100 rpm range, and about equal in the 5200 rpm on up to 7200. The Concours peak HP difference is primarily due to the higher redline and not in any area that many folks will ride. It does, however, have a slightly smoother power delivery curve than either of the other two bikes, but is really crappy below ~ 3500 rpm.

 
2012-Honda-ST1300-vs-Kawasaki-Concours-14-vs-2013-Yamaha-FJR1300A-hp-torque-dyno.jpg

The above dyno plots are quite interesting. Even though the Kakasucky Concours has a ~100cc displacement advantage, the FJR has more torque over the 2200 - 4100 rpm range, and about equal in the 5200 rpm on up to 7200. The Concours peak HP difference is primarily due to the higher redline and not in any area that many folks will ride. It does, however, have a slightly smoother power delivery curve than either of the other two bikes, but is really crappy below ~ 3500 rpm.
I'd love to see a Harley plot before and after illegal modifications thrown on there.... :)

 
I doubt you'll ever see a plot from a stock Harley....
Perhaps not from The Motor Company, but the tuners don't mind showing you how weak a stock Harley Motor is:

dyno10697topendkits2010.jpg


It still takes S&S over 1700 cc's of displacement to get near 100 HP.

 
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It still takes S&S over 1700 cc's of displacement to get near 100 HP.
Fair play. But consider how much higher the emissions are because of all the speed parts that it takes to get there. It's not just the tuner boxes that are affected by the precedent the EPAs childish tantrum has set. Under their previous blanket-ban proposal, ANYTHING that altered the emissions from standard would be illegal. I think HD was just an easy target because of the emissions agreement that was mentioned earlier.

 
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2012-Honda-ST1300-vs-Kawasaki-Concours-14-vs-2013-Yamaha-FJR1300A-hp-torque-dyno.jpg

The above dyno plots are quite interesting. Even though the Kakasucky Concours has a ~100cc displacement advantage, the FJR has more torque over the 2200 - 4100 rpm range, and about equal in the 5200 rpm on up to 7200. The Concours peak HP difference is primarily due to the higher redline and not in any area that many folks will ride. It does, however, have a slightly smoother power delivery curve than either of the other two bikes, but is really crappy below ~ 3500 rpm.
And the FJR's torque curve is pretty peeky across the range. It could benefit from some custom tuning to make that curve more even between 2300 and 2800 and again between 3900 and 5200. The HO curve below 5500 is pretty "snakish" too.

I know some of that has to do with 5200 being a constant in the calculations but those 2 areas also just happen to be prime EPA RPM ranges.

The Concours (above 3500) is the type of curve to shoot for (without going for the bragging rights of total HP/Tq at the cost of lower end response (more sporty in nature than s/t).

 
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So you're saying Yamaha needs to add variable valve timing and actually optimize the airbox? I'm game.

 
I'm certainly not arguing that. I'm right there with you in fact. But that hole will be there even without the tune being compromised by the EPA. The airbox and exhaust are also compromised by noise regulation. And the airbox is further compromised by where it's packaged on the bike. Look at how much gets filled into the low end of the curve with a chop job done. Just say'n. The EPA can get it's mitts on anything that affects the way the bike runs and regulate it into an unrideable pile of scrap.

On the other hand, I wonder how the handling would change with a tank and intake setup like the C14 has... probably wouldn't be better.

 
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No I'm saying what I originally said, the EPA mandates screw up a proper tune.
I agree the dip could be tuned out, but quite honestly I've never felt it while riding, so it is less pronounced in real life than it appears in that plot. I'll have to search around and find some 1st and 2nd Gen Dyno runs to compare it to.

It does have me wondering, though... That is the exact rpm range that the FJR has the (most) vibration buzz in the handlebars. My experience tuning the 1st Gen FJR was that if I added fuel to reduce leanness it would smooth away some of the engine vibration.

So I wonder if perhaps the 4k rpm buzz in the 3rd Gens is exacerbated (I know it is not caused ) by lean fueling in that range? Lean fueling could be responsible for that dip in torque.

(edit - This may be worthy of a thread split)

2nd Edit: While searching for FJR Dyno Runs, I stumbled across this thread on this very forum. I remember the thread now, and that the dip in torque is an intake phenomenon that Useless Pickles got rid of by opening up the airbox, at the detriment to top-end power.

So it may still be EPA related (noise), but possibly also "tuned in" there for better high rpm power.

 
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A 50% increase in hp for about $3,000 all in for the Harley-Davidson isn't that bad...$100 per horsepower gained. In the end you end about 30 horsepower shy of the R6 but up by 50+ in the torque department.

 
And you've still payed twice as much and are carrying and extra 300lbs at all times with no upgrades to the stoppers on your "faster" bike. Plus the R6 is still EPA compliant in that comparison. It's a little apples and oranges.

 
considering even the lowly HD will reach speeds above what is allowed on each and every North American roadway, WTF cares?

farkle away, regardless of make/model, and enjoy yourself

everything else is just a pointless pissing party

 
Actually I could see the Canadian contingent rooting for the EPA. We'll all have to smuggle speed parts from up north if they win. ;)

 
considering even the lowly HD will reach speeds above what is allowed on each and every North American roadway, WTF cares?

So will a CBR250. So, why bother buying anything faster (and more fuelish) than that?
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But wait...The Motor Company has this lurking in the wings in case you haven't noticed...sure to set the motorcycle world on it's collective ear...

https://www.motorcyclecruiser.com/harley-davidsons-new-engine?src=offramp&loc=region-2&lnk=txt

Hopefully other manufacturers will follow this lead...

"What we did is that the hydraulic lifters for each pushrod now account for thermal roll from the engine. We have no adjustment. It’s factory set for life. We came up with an arrangement to set for very low lash at the factory and maintain that for the life of the motor."

 
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That was about the only detail that guy gave about any changes to this engine. The rest sounded a lot like marketing puffery. It was interesting and germane to this thread that they mentioned the new valve train and how it would interface with aftermarket cams. I think he made a mistake, or the writer did, as the parts needed would be adjustable rockers, not non-adjustable ones.

 
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