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S&S Dragon T143 is the Answer to Every HD Bagger Performance Question

By Paul Crowe

S&S Dragon, the Harley Davidson Road Glide Ultra with an S&S T143 engine, 160 horsepower at the rear wheels, 170 pound feet of torque and nine second quarter miles
S&S Dragon, the Harley Davidson Road Glide Ultra with an S&S T143 engine, 160 horsepower at the rear wheels and 170 pound feet of torque

After the review of Motorcycle Drag Racing: A History, my eyes kept stumbling over anything related to acceleration and while checking out the April issue of Cycle World, there it was, the S&S Dragon, a Harley Davidson Road Glide Ultra, not something you would normally associate with performance, but this one is different, it’s equipped with the S&S T143 Long Block engine, the largest offering in their catalog that fits in the stock bagger frame. That’s 143 cubic inches (2,343 cc), over 160 rear wheel horsepower and 170 pound feet of torque, … in a Road Glide Ultra. No, this isn’t really for cruising, this is for drag racing, but it does cruise just fine.

Of course, if the only thing you swapped out was the engine, the rest of the bike wouldn’t be up to the task, the Dragon has Ohlins suspension, Lyndall discs, Brembo calipers, Pirelli tires, plus a long list of parts from S&S, DynoJet, Brock’s Performance and lots more, a 3 inch primary drive, big clutch, a chain drive conversion, carbon fiber wheels, an air shifter and lots of time and effort putting it all together.

Price for the engine alone is north of $9,000 plus all of those extras before your bike is ready to go. The CW article says the Dragon is a $40,000 package, but you’ll have the fastest bagger in town. Yes it’s expensive and sport bikes are cheaper, but on the fun factor scale, this might make a pretty good trade off.

I like this from S&S on their T143 page:

At double the HP of a stock motor the power of the T143 requires technical expertise for the installation and tuning along with an experienced rider. This is an ultra performance/ race engine. Longevity, engine noise, vibration and throttle sensitivity have all been compromised to reach this level of performance while fitting in a stock chassis and as such is not suitable for every situation.

Ya think? OK, but it looks like the most fun you’re ever going to have on a big Harley, so you can expect quite a few guys with deep pockets to be lining up.

OK, OK, I know you’re not really interested, but the video below shows the eighth mile at 6.82 seconds and 106.58 mph. S&S says the quarter is in the nines, … on a bagger. Wouldn’t it be neat to roll up next to a Ninja or an R1? 🙂

Link: S&S Dragon

Posted on March 7, 2016 Filed Under: Motorcycle Business


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Comments

  1. todd says

    March 7, 2016 at 12:40 pm

    OK, let’s think about this… R1 has 160+hp at the rear wheel too but weighs 438lbs topped up and ready to go. The Ultra Glide, on the other hand, weighs twice that at 870lbs…

    The only thing keeping the (stock, every day commuter-worthy) Yamaha from getting into the 9’s is the 100 mph first gear and it’s light weight allowing the front wheel to lift off the ground way too early. If it was as low as this, with improved gearing, and also had the same rear car-tire slick it would likely do a bit better.

    But, yeah, this thing is impressive.

    • Paul Crowe says

      March 7, 2016 at 1:11 pm

      A quick Google shows last year’s R1 had 77 pound feet of torque, this S&S unit has over 90 pound feet more than that! More than double the R1.That moves a lot of weight quickly.

      The rear tire in the video as they warmed it up was no slick.

      • todd says

        March 7, 2016 at 9:06 pm

        Remember, Paul, more torque at a lower RPM means the gear ratio needs to be raised to achieve the same speeds. Raising the gear ratio reduces acceleration. It’s easiest to compare power. If you insist on using torque for comparisons, look at rear wheel torque ( engine torque times overall gear reduction) at a given road speed. The Yamaha has a lower gear ratio than the Harley so it’s torque at the rear wheel for a given speed is the slightly higher than the modified Harley (you know this because the power is higher).

        Designing vehicle powertrains used to be my line of work, trust me on this one.

        • Paul Crowe says

          March 7, 2016 at 9:48 pm

          What’s trust have to do with it? My original point in the post was meant to convey the obvious fun it would be to run with and perhaps beat an R1 while riding a Harley Road Glide, not to mention seeing the look on the R1 rider’s face.

          More than twice the torque with equal power means you can move a lot more weight just as quickly. In a drag race, ET wins the race, not speed. I don’t know what the relative gearing is on this bike vs an R1, but the ET and speed in that video says more than any recitation of powertrain theory. It would be similar to Samuel Johnson’s famous “I refute it thus!” when he kicked the rock after it was verbally proven that matter does not exist.

          I guess I’m not sure what you’re even debating here. Are you saying a bagger running nines in the quarter isn’t as quick as an R1 doing the same? Or am I missing something entirely?

          • todd says

            March 7, 2016 at 11:53 pm

            Not at all. I’m saying 160hp is 160hp. Even though it has more torque it is not more powerful, it has the same power. Having the same power means they both have the same thrust (torque at the rear wheel). And both can accelerate the same mass at the same rate.

            They are equal in terms of engine output, way different in mass, therefore different in performance. Torque at the crankshaft does not tell you anything unless you know what sort of rpm you are spinning for any given speed. That will tell you what sort of gear ratio (leverage) you have. Remember my bicycle analogy? A bicycle rider puts out between 100 and 150ish lb-ft of torque at the crank. That doesn’t mean a bicyclist can pedal a Road Glide into the nines in the quarter mile. Torque is not some sort of extra special power. It’s not power at all.

            You need to go back and understand what power is and what it’s relationship to leverage and rate (rpm) and how torque plays into that.

            Yes, this bike is interesting and impressive. Yes, a rider on an R1 would be amazed that a cruiser could keep up with him – potentially passing him a little since the R1 rider is fighting to keep his front en on the ground. Would I want this bike to ride vs an R1? Well I don’t want an R1 but if I had to rely on either if these bikes for my daily transportation and comfort like I do with my slow old BMW, then I’d take the Yamaha.

          • Wave says

            March 8, 2016 at 4:35 am

            Todd is definitely right on this one. Power is the ability to do work over time.

            Paul said, “More than twice the torque with equal power means you can move a lot more weight just as quickly.”

            Do you remember the old definition of horsepower? A horse, powering a winch to lift a certain amount of weight by a certain distance, during a certain period of time. That is what power is, the ability to do work (move weight) over time. The horse doesn’t even have torque, it is pulling the rope with a force in a straight line.

            • Paul Crowe says

              March 8, 2016 at 8:11 am

              Oh, I’m familiar with what it is:

              What is Horsepower and Torque?

              And in the interest of science, there’s Hildo 🙂

              As I questioned above, I’m not sure what we’re even debating here. If the S&S engine gets the Harley down the drag strip as quickly as it does, that’s really cool, why make a counterpoint about the R1 in a coulda, woulda, shoulda kinda way? Lower it, change gears, maybe a long swing arm, whatever, the Harley is still ripping off some extremely quick ETs that will match or embarrass an R1. With more distance the R1 will easily outrun it with a higher top speed, but that’s not the race.

              I am not a member of the Church of Horsepower or the Church of Torque so I really don’t have a “horse” in this race, but some people seem to take offense to big V-Twins being so quick and they want to defend the honor of the sportbike, I guess. Or maybe I’m just missing something.

              • todd says

                March 8, 2016 at 9:41 am

                Sorry for the rant, Paul. I’m defending physics, not sport bikes. I don’t even own a sport bike unless you can call a V-twin Monster a sport bike. Most of my bikes are twins. I do have lots of experience riding many different types of bikes and I’ve done lots of drivetrain tests and comparisons for work. There is a lot of misinformation out there about the virtues of torque, so much so that everyone forgets how leverage plays into it.

                Someone asks you if you want a handful of 50 dollar bills or a handful of 100 dollar bills, which would you take? That’s the torque debate and the torque proponent would take the 100 stack every time. The horsepower guy would ask, “how much money is it?” because there could be ten 50’s in one hand and two 100’s in the other.

                • Dave says

                  March 9, 2016 at 10:37 am

                  Now my head hurts…

                  • Lostboy says

                    March 10, 2016 at 9:30 pm

                    Mine too…

  2. Bob says

    March 7, 2016 at 7:34 pm

    This – in something like one of Curt Winter’s bikes…

    • Paul Crowe says

      March 7, 2016 at 8:28 pm

      That’s not a bad idea. This bike with that engine, … oh, baby.

  3. Oldernowiser says

    March 8, 2016 at 9:06 am

    What is Horsepower and Torque?

    I stayed up all night running the numbers and found that no matter how you phrase the equation, any combination of the aforementioned horsepower and torque which results in the front wheel of a bagger off the ground under acceleration as shown in the video = fun squared.
    It’s kind of like the speed of light….always the same….at least from this observer’s perspective……:-)

  4. Carbon says

    March 8, 2016 at 5:04 pm

    Loving the bagger’s “clip-ons” or whatever they are. That thing is fantastic!

  5. alan says

    March 11, 2016 at 6:44 am

    numbers don t lie , how many hp at how many rpm is the point .I just know the 160 hp r1 at 5000 rpm makes ………60 hp , I m impressed …… just the same as an old stock pushrod v twin ….

  6. steve w says

    May 12, 2016 at 10:21 pm

    Until you have ridden a high horsepower high torque big heavy bike don’t just guess what it is like. It can friggin’ scare you half to death. It doesn’t handle but what a ride. I still remember the first time I rode my 130+ RWHP 124″ bike and downshifted to pass a car and wacked it full throttle. Only to realize I wasn’t pointed straight ahead and the edge of the road was there in an instant. These things don’t do what sport bikes do but that’s the fun factor. Maybe it’s called pukker factor. It’s just plain fun. I continued to ride that bike 67,000 miles and now have a new one ready to roll. It’s kind of like if you tried to drive a 1963 Indy car that didn’t go as fast as a new Indy car but you were still on the edge because it was doing everything it was capable of.

  7. Gregg Hodge says

    October 15, 2016 at 4:00 am

    Oh yeah, I remember back in the early 90’s (and before) when HDs were snubbed fully and completely by the sport bike/fast bike crowd. The main preppy(CW etc) bike magazines were right there insulting and making fun of my beloved brand. Then the Evo came out and the Honda Davidson jokes faded away as it became clear Harley wasn’t going under just yet….Flash forward to today. HD is healthy as a Motor Company can be in these expendable income challenged lean years. The quality and even the performance of the new Harley’s are light years ahead of the AMF bikes of the early 80’s. Harley’s have ruled Pro Stock for ten years or so. The anti-Harley stigma still lingers, but these days when I roll up to a ‘sport bike’ at a red light the smug look I often got from the sport bike pilot has been replaced by one of uncertainty and yes maybe fear, especially if he has his girlfriend with him. Well my sporty is far from stock but still it feels good to have arrived!

    Disclaimer; Don’t get me wrong, I love all kinds of bikes, and have the need for speed. That is why I am in the process of buying an Japanese inspired BMW. My beloved Harley Motor Company did not have a bike to do what the BMW or a Ninja can, if it did I would have bought HD (again).

  8. Rob m says

    October 23, 2016 at 10:42 am

    Well here we are again comparing a sport bike to a Harley which is just apples to oranges. Two distinct animals with different purposes , one is made for solo riding with your buddies and getting your knee to the pavement in the curves , the other will get you laid every time 🙂 A true motorcycle enthusiast can appreciate both concepts..

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