Speed Glider

Radical Rider

Dark Hopper

customized Harley-Davidson Softail Slim S

Why Slim?

Harley riders have long memories. Ten years ago, they wondered why the Slim model had that name. With its wobbly 16-inch tires, it rolled on anything but a slim foot. The Slim, with its promise of slenderness, always looked a little disproportionate, if not chubby. The Softail Slim was a model for the 2010s. These were the last years of the Twin Cam engine, which was still available in the A and B series, with and without balancer shafts.

As a Softail, the engine rotated on balancer shafts, so it was B, for “balanced,” and originally had 103 cubic inches, or 1690 cubic centimeters of displacement. Here we have a 110cc S version with Screamin’ Eagle components, which means 1802 cc. Built in 2016, it is one of the last Twin Cams, just before being replaced by the Milwaukee Eight. Something you can and should love.

Challenge accepted

Some parts of the customer’s bike had already been modified, which is the fate of every Harley. But we like to keep working on it. So we took the challenge of making the Slim a really slim bike all the more seriously. Our main focus was on the wheels. And because we are customizers, we also gave the rear end a total makeover.

Complete rear set

This is not just a matter of taste, but a practical necessity, because what is so slim about the massive rear end of the original Slim with its sweeping fender struts? Our FLH wheels are slim! This is due to their slender spokes and especially to their larger diameter. The front wheels are now 21 inches with 130 mm wide tires. The rear wheels are 18 inches. Their 200 mm tires don’t look fat at all, but rather powerful.

Our Recall front fender, makes for a slim front

Perforated struts are part of our rear fender swing control program

The Dark Hopper owes its slim rear view not only to the FLH wheel, but to the entire ensemble. The brake disk has been moved back to the left between the wheel and the pulley. It is a disc from our Spoke series, whose black spokes could make a soup plate disappear into a delicate nothingness.

Of course, all of this is only impressive because the standard fender and struts have also disappeared. With our Flying Slim concept, the Dark Hopper now has a custom swinging fender held up by custom perforated struts and topped off with a mono tail light. We swing the Spirit Leather saddle with airy hairpin springs. Not only does this give the bike the look of a rigid frame, but it also streamlines the bike. Of course, everything is lowered. This applies to the rear as well as the front end, which has the physical side effect that the fork geometry hardly changes despite the significantly larger front wheel. The narrow Recall front fender is part of the streamlining concept. So the line is right and the former slim is now really slim.

We make the spoke brake disc between the rear wheel and pulley

For the swing saddle rear fender, we also supply the hairpin springs

Here, the 200mm tire looks strong, not fat

We put our hands on

We wouldn’t be Thunderbike if we didn’t have a few more things in our hands. This is especially true for the Jekill and Hyde system, which conjures up an appropriate and legal sound at the push of a button. Combined with our Grand Classic air cleaner, this literally gives the Dark Hopper a boost. That leaves the splashes of color, which in our case are powder coatings.

Parts & Details

All glossy black, because black is not only always the right color, it also makes you look slimmer. So we have arrived. And so has our customer. It may be difficult for him to explain to other bikers that they are looking at a former Slim. They will certainly understand better if he explains to them that Thunderbike made it.

  • Thunderbike FLH wheel
  • Thunderbike Brake Disc Spoke Floated 300mm
  • Thunderbike Brake Disc Spoke Floated 292mm
  • Thunderbike Pulley Brake Kit
  • Thunderbike Pulley Spoke polished
  • Thunderbike Extra Charge Pulley Powdercoating black
  • Thunderbike Fork Lowering Kit
  • Thunderbike Mounting Kit Fellow S & FredBob
  • Thunderbike Rear Fender Steel 200 mm / 18''
  • Kellermann Bullet Atto Dark Turn Signal Set black/smoke
  • Thunderbike Lowering Kit OEM Shock Absorber 35mm
  • Thunderbike Powerfilter-Kit Grand Classic

Author / Editor

Michael Ahlsdorf

Your contact


Thomas Emky

Custombikes Service Workshop

0049 2852 - 6777-56
Send an email


Julian Segler

Sales, Financing, Rental, Custombikes

0049 2852 - 6777-41
Send an email


Roman Reiners

Customparts, Dealer Support

0049 2852 - 6777-30
Send an email


Nico Schnepel

Customparts, Dealer Support

0049 2852 - 6777-30
Send an email

More Slim Customs

You can find Thunderbike Parts and original Harley-Davidson Parts  in our online shop.


Stay up to date with the Thunderbike newsletter. In our free newsletter you will find news on our custom bikes & parts, information on Harley-Davidson models, all important dates & events, used vehicles, accessories, clothing, promotions and much more! The subscription can be terminated at any time by unsubscribing in our newsletter. We refuse to disclose your data to third parties. You will receive an e-mail confirmation after the subscription. So we make sure that no unauthorized person can register you in our newsletter.