This Custom Fat Boy Packs a Massive V-Twin Heart

All-Rounder

Germany's Thunderbike has long held a stellar reputation for churning out some of the coolest custom motorcycles on earth, whether they be based on a stock Harley-Davidson or 100 percent custom, from top to bottom. Their latest is a cool take on a Fat Boy that's been nicknamed "Fat Back," one that goes every bit as good as it looks.

Photos: Thunderbike

Big Power

The heart of this particular beast is something special, particularly since many builds these days simply stick with a stock engine that has been treated to nothing more than exhaust upgrades. Instead, Fat Back utilizes a 131-inch Screamin' Eagle powerplant that makes a healthy 130 horsepower.

Photos: Thunderbike

Birthday Bike

To that base, Thunderbike also extracted a few more ponies by adding a Dr Jekill & Hyde exhaust system, as well as an upgraded air filter. These modifications - along with a host of others - are also notable because this isn't just any old Fat Boy. Rather, it's one of just 900 units built to celebrate the motorcycle manufacturer's 115th birthday.

Photos: Thunderbike

List of Upgrades

That rarity didn't stop the owner from wanting more, and Thunderbike obliged by giving this Harley a chopped subframe, a new rear fender, a single-sided swingarm, and custom alloy wheels at both ends. Other highlights include a perimeter rear disc brake and 340mm unit up front, a new engine fairing, a rear air suspension, and lowered front forks.

Photos: Thunderbike

Nifty Touches

From there, Thunderbike complemented the cool factory Legend Blue Denim paint job by adding gloss black components to replace all the chrome pieces, matching satin blue paint for all the new parts, a leather seat with honeycomb stitching, and new, taller ape hangers, forward controls, and custom mirrors.

Photos: Thunderbike

Better Everywhere

This particular build perfectly sums up what's possible with the right combination of upgrades and cosmetic touches, even for a rare factory ride like the anniversary Fat Boy. Once flashy and old school, this bike is now more understated and sinister looking - not to mention considerably quicker than its stock counterpart. 

Photos: Thunderbike

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