2021 Harley-Davidson Softail Slim Dyno

We put the 2021 Harley-Davidson Softail Slim on the Cycle Word dyno, recording horsepower and torque measurements.

The 2021 Softail Slim is a classic-styled American cruiser that’s built upon—I’m sure you guessed it—Harley-Davidson’s Softail platform. Powering the Softail Slim is Harley-Davidson’s eight-valve Milwaukee-Eight Big Twin 107ci (1,745cc) engine, which is also seen in the current Softail Standard and Sport Glide as well as some Touring models. But what sets it apart? Stripped-down styling with cut-back fenders, floorboards, and relaxed ergonomics.

We strapped the Softail Slim to our in-house Dynojet 250i dyno, recording horsepower and torque measurements ahead of an upcoming comparison test. The Harley-Davidson produced 73.66 peak horsepower at 4,860 rpm and has a very linear, rider-friendly delivery on the way there. Note the torque curve’s usability as it shoots up from 1,300 rpm and steadily climbs to its 98.39 pound-feet peak output at 2,790 before beginning to taper off at 3,000 rpm.

[carolstrong]

I just bought the 2021 Slim. Absolute beast!

[guitarocker]

Love my 2020 slim. Absolute torque monster.

[robertyoung]

Yeah thank you for giving us real real numbers on the Dyno numbers for these Milwaukee 8 “107”!!! Harley Davidson wants to give the Dyno numbers from the crank that or miss leading to buyers if they don’t know the difference!!!

[GrecoRoman]

Came for the Harley hate comments. Yup, there they are.

[jhackett]

That torque is awesome. We don’t ride HD for the HP. That thing could plow a field with a knobby on.

[Chase_N]

lol, my 2013 TwinCam 103 did 76HP & 99TQ on a Dynojet dyno last year with just slip ons. I can't wait to see what it does with a tune, air cleaner, breather bolts. How TF does HD get worse numbers on a bigger engine?

[keithappel]

Kind of out of text but guys I’m buying a bike this year I love the FTR. But I like to try amp RS 1200 that’s coming out and of course the 890 duke the problem is I live in South East Michigan and guys I am limited if you can help me at all with trying to find these motorcycles other than the Indian In my area where I can drive it or rather ride this I would truly appreciate it

[a.kirkpatrick]

Can you guys put the new Multi V 4 S on the dyno?

[TROllingNINJA]

You can only squeeze so much out from old tech

[jonathan]

The engine is massive, but the hp and torque is not. 🤷🏻‍♂️

[joeplem]

" Harley's are slow" if you leave them stock

[cajunmandick]

Stop it, .74 hp?, My R1 yamaha makes that much on two cylinders. What a joke, maybe you could see how much hp a john deere tractor makes in comparison, they're kinda the same.

[dieselboy]

So, what I got from this vid is: don't buy a Harley, buy an Indian, if you must have an American cruiser.