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Does that also restrict their own remapping (for example, for the full Akra)?

And does that restrict operation of aftermarket fuel controllers?
Good question. Yes. The stock and akra are the same HP at 6000rpm but the torque is improved.
 

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Yup...unfortunately they are so good they have locked down the ecu at 6000rpm too. That is menacing.
I'm sure given time there will be a clever person that will be able to crack the ecu coding. The more manufacturers that lock down ecu's the more of an incentive there will be to crack them.
 

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I feel like a broken record. The engine is limited by the 11 degree valve timing. It's what gives us such a pleasant torque curve, but restricts top end power because it restricts flow through the valves at higher RPMs (HP = Torque / Time). The 848 Superbike (same basic engine with less capacity and different cams) made 122 HP, our 939 makes 110. Fancy aftermarket exhausts are made to be less restrictive so the heads can flow more air, but the 11 degree heads in the SS and Hyper are limited by the cams, not the exhaust.

However, these motors make amazing torque down low, where street riders and canyon carvers want it. It's a use-case proposition. The 1200 barrels and pistons with the 11 degree heads might just be perfect, and likely get up to 155 HP (the 1198 made 170 HP with high flow heads), assuming you can do something about fueling. I feel pretty certain, given Ducati's model record, that we'll see this very bike in another few years, once the demand for the 939 settles down.

Al that said, there's always someone who still wants even more power.
To add to this, the 11 Degrees is overlap where the engine has all four valves open. So whilst the exhaust gases are being released through the open exhaust valves the injectors are also releasing fuel through the open inlet valves.
What will have been better is the DVT Testastretta engine. It uses the oil pressure to adjust the valve timing, so at lower revs the overlap is reduced and at higher revs the overlap increases to improve the efficiency of the engine by optimising the fuel consumption at varying RPM ranges. THe DVT Testastretta was released in 2014 but never made to our SS. Perhaps the next model will have the DVT engine....with 1200cc bore, since its already on the multistrada.
 

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Perhaps the next model will have the DVT engine....with 1200cc bore, since its already on the multistrada.
Wouldn't this add to the overall weight, though? I'm not in the camp of adding any more weight to this bike. It is very balanced as is.
 

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To add to this, the 11 Degrees is overlap where the engine has all four valves open. So whilst the exhaust gases are being released through the open exhaust valves the injectors are also releasing fuel through the open inlet valves.
What will have been better is the DVT Testastretta engine. It uses the oil pressure to adjust the valve timing, so at lower revs the overlap is reduced and at higher revs the overlap increases to improve the efficiency of the engine by optimising the fuel consumption at varying RPM ranges. THe DVT Testastretta was released in 2014 but never made to our SS. Perhaps the next model will have the DVT engine....with 1200cc bore, since its already on the multistrada.
I suspect the DVT system is incompatible with the head-mounted frame, probably the same reason there isn't a DVT Monster.

If it can be made to work, I'd like to see a different profile developed that maintains elevated torque, rather than the Multi's preference for fuel economy.
 

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I suspect the DVT system is incompatible with the head-mounted frame, probably the same reason there isn't a DVT Monster.

If it can be made to work, I'd like to see a different profile developed that maintains elevated torque, rather than the Multi's preference for fuel economy.
It seems to be an eccentric cam with the oil pressure changing the cams position. Google the DVT testastretta.
 

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It seems to be an eccentric cam with the oil pressure changing the cams position. Google the DVT testastretta.
I'm familiar with how it works, though this is a good suggestion to others who aren't and why they should be interested. The Monster 1200 without DVT is 145 HP, The Multi 1260 with DVT is 158.

There were probably structural changes made to the DVT head to accommodate the mechanicals of the system, most likely additional oil passages to pressurize the mechanism. The DVT head was made for a motor that mounts in the chassis at the block as with the Multi and Hyper. The difference being our bikes (SS and Monster) don't mount the chassis at the block but mount it at the head. The point being that the changes for DVT on the head are probably incompatible with mounting the chassis at the head.
 

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2017 Ducati Supersport, 2015 Ducati Scrambler Classic, 1994 Ducati 907ie
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I'm familiar with how it works, though this is a good suggestion to others who aren't and why they should be interested. The Monster 1200 without DVT is 145 HP, The Multi 1260 with DVT is 158.
I think more to do with the cams and ECU mapping. The non-DVT Multi 1200 made 150 hp and the Diavel with the same engine but a freer flowing exhaust made 160 hp.

There were probably structural changes made to the DVT head to accommodate the mechanicals of the system, most likely additional oil passages to pressurize the mechanism. The DVT head was made for a motor that mounts in the chassis at the block as with the Multi and Hyper. The difference being our bikes (SS and Monster) don't mount the chassis at the block but mount it at the head. The point being that the changes for DVT on the head are probably incompatible with mounting the chassis at the head.
Looking at the parts lists for both models, at first I didn't think DVT would prevent adoption of a head mounted frame. The SS heads are virtually the same as the DVT heads but they have bosses cast into them for the attachment of the frame and rear subframe. Then I spotted that the DVT heads have a casting at the horiz inlet position and the vert exhaust position to accommodate an electrically operated valve for the DVT mechanism. This is located exactly where the horiz cylinder frame mount would be and where the vertical cylinder mounting for the rear subframe is. Different castings and frame would be required.
 

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Did anyone remove the baffles from stock exhaust? I know this is old topic but search through I couldn't find it searching thru
 

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Not heard of anyone removing baffles from stock cans as 95% of noise reduction is in the CAT not stock cans. When I removed stock cans to install Akrapovic ones I started bike with no cans at all and bike sounded almost exactly same, volume and tone, as with cans... It might be a touch deeper tone with Akrapovic but otherwise not much difference.

As for CAT gutting, how about someone coming up with a complete removal of CAT then fabricating pipes to accept Akrapovic baffles ? Now that would really peak my interest...
 

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Yeah, I did all that exhaust craziness with my HD fatboy lo (I know typical hd owner) but as for my SS Im thinking a cat delete and DONE. stock pipes look great! and with the cat honeycomb gone Ill have a lil more grunt and less heat on my heals. Wouldn't mind looking into a full system that doesn't route up and out near the tail (akr full sys and DQ) they sound good just not crazy about the look.
 

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Noise aside, I opted for the Akro slip-ons because the stock cans look unfinished, as if they need a decal or something. The slip-ons aren't noisy at all and I can't imagine they are much louder than stock, but I like the way they look. A little pricey for some atheistics, but there you are.


Pjk
I totally agree. Like others here the SuperSport is a relatively tame thing of beauty. I fell in love with its gorgeous lines. But the stock exhaust looked so unfinished, detracting from the rest, as if they ran out of time or money to finish the job properly. Don’t get me wrong, I also fell in love with the cackle / burble of the stock exhaust; it just never looked the part.
 

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I have a spare cat and silencers that I was going to gut and weld back up. It is up for sale in the ad section now if anyone else wants to have a go cheaply?

Matt
 
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