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What seems promising is how linear the Rev X is laying down the power, even that flat torque curve seems to be unbeatable. The Monster looks like the only one who matches the Street 750's linear delivery albeit with a $2000 premium on the Duc ;)
 

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beats both bolt and iron by some margin , the heir to the sportster lineup .

Monster clearly the fastest of the lot but then it is a ducati with pure performance in mind .

What I will like to see is a comparision with the boneville as the street and boneville fall more or less in similar engine tuning category , the boneville will obviously be more powerful but CC for CC , I think both are more or less same which is good.
 

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Factor in the heartbreak of maintaining a Ducati. Ever study the valve adjustment procedure for a desmodromic valve train? No thank you. Cam belts that have to be replaced every other valve adjustment (many owners simply replace them every time since they are off the bike anyway) and then there is the finicky process required to tension those belts correctly. You can have it. The Street makes a lot more sense.
 

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Hey guys, I'm not that familiar with dyno runs so these charts don't mean a lot to me. How about a little lesson on how these charts translate into real life driving experience. Glad to hear that the HD Street is performing well, even if I can't really make sense of it myself.
 

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Torque is a measure of instantaneous force available at a given time while horsepower is a measure of work, or force applied over a distance. The formula for horsepower is:

HP = (Torque X RPM)/5252

This is why an engine that can generate more rpms will make more horsepower than one that does not, assuming you can fill the combustion chamber and burn enough fuel to keep torque high. Horsepower is what moves the bike down the road.

If you look at the power curves for the Star Bolt and Harley Sportster 883 Iron, you see they make their peak torque at very low rpms, only 3000 for the Bolt and about 4000 for the Sportster. That is where they will accelerate the hardest. Beyond that their power tapers off rapidly.

If you look at the torque curve for the Street and for the Ducati, you see torque comes up early and is a flat line across several thousand rpm. This means the engine will accelerate hard all the way through the rev range, not just a small rpm band at the bottom of the rev range. These are more flexible engines. It also explains why they both make more horsepower. Both have more efficient combustion chambers and are able to maintain torque over a much wider rpm range. Since more rpm means more power as long as you can maintain torque, which the Street and Ducati do very well, they make more horsepower and the bike will be faster and accelerate harder at more rpms than the Iron or Bolt can.
 

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but the bikes tested were pre-production bikes.. so is it possible final finished product is less powerful?

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but the bikes tested were pre-production bikes.. so is it possible final finished product is less powerful?

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Final delivery bike will be more or less same in every sense as what they are calling pre production bikes . I will suggest expect the exact same bike that was available for test ride , any changes if done will be for the better - say brakes or better wire management for example . Performance will be same as well , however it is not necessary that the bike made in/for india might have the exact same performance as the one made in/for USA but I expect similar examples , any differences if present will be nothing significant Imo .
 

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Final delivery bike will be more or less same in every sense as what they are calling pre production bikes . I will suggest expect the exact same bike that was available for test ride , any changes if done will be for the better - say brakes or better wire management for example . Performance will be same as well , however it is not necessary that the bike made in/for india might have the exact same performance as the one made in/for USA but I expect similar examples , any differences if present will be nothing significant Imo .
But we are seeing changes like earlier torque was mentioned as 65nm everywhere but now its 60nm, earlier and test ride bikes are having 150 profile rear tyre, now they say 140.

so things are varying

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But we are seeing changes like earlier torque was mentioned as 65nm everywhere but now its 60nm, earlier and test ride bikes are having 150 profile rear tyre, now they say 140.

so things are varying

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True that , even I was told 65nm at 4k rpm when I went to the dealer .
 

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True that , even I was told 65nm at 4k rpm when I went to the dealer .
yes I have 65nm and 150 rear profile written in brochure by HD

and now they havr changed

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But we are seeing changes like earlier torque was mentioned as 65nm everywhere but now its 60nm, earlier and test ride bikes are having 150 profile rear tyre, now they say 140.

so things are varying

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I put my Street Rod on two different dynos on two different days and saw six horsepower difference in output between the two dyno runs. No changes were made to the bike, it was purely the result of differences in the dynos.
 

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but the bikes tested were pre-production bikes.. so is it possible final finished product is less powerful?

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Not if Harley is smart. They know those bikes will be dyno tested by a couple of dozen magazines. If their claimed power is a load of bovine excrement, the magazines will be all over it. Magazines love to discredit manufacturers that way. If anything I would bet Harley's power claims are slightly conservative to protect their reputation. Don't forget that the horsepower and torque figures will vary for each dyno used to test these bikes, no two dynos are the same, and likewise no two production motorcycles will make identical power. Use a little judgment here.
 

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More charts

Hi,
Those graphs are excellent.
Any chance of comparisons with the Ducati Scrambler, the old and new Triumph Bonnevilles, Moto Guzzi V7, the Kawasaki W800 and the Yamaha XSR700?
Ta
 
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