This Is The Biggest Harley-Davidson Stock Engine You Can Get In 2026
Harley-Davidsons are the quintessential American motorcycle. Your average Harley is huge, loud, and blinged-out in what seems like miles of chrome. That brashness is one of the main reasons why the brand has been popular for over a century — but that's not the only appeal. Harley-Davidson engines are a potent part of the mix, too, and given that there's no replacement for displacement, figuring out the biggest Harley engine available in a stock motorcycle is a fair pursuit.
Taking a look through the lineup and the answer to the question jumps out pretty quickly. It's the 121 cubic-inch Milwaukee-Eight V-twin that powers many H-D bikes. One such bike is the top-of-the-line Street Glide Limited, which, at $51,999, costs several times more than other big touring bikes like a Honda Gold Wing or Yamaha FJR.
Despite the Street Glide Limited looking like it's from the 1950s, Harley's V-twin engine is a fairly modern powerplant, boasting features like variable valve timing and electronic fuel injection. All told, it makes 115 hp and 139 lb-ft of torque.
Bigger than the competition?
Vying for American riders' hard-earned dollars is Indian Motorcycles. Its biggest and most expensive bike is the Indian Pursuit Elite. How does its powerplant compare to the Milwaukee-Eight from Harley? Well, the Pursuit's engine is smaller, with a displacement of 112 cubic inches. However, the Indian makes more power, with 126 hp, but slightly less torque at 133 lb-ft. The Indian is also less expensive, although still very pricey at $44,999.
The Harley's V-twin is also much larger than the Honda Gold Wing's unique engine, which is a 1,833cc (111-CI) flat-six. The Goldwing has 125 hp, just a tad more than the Harley. The most expensive Gold Wing, the automatic model with an airbag, retails at $33,800 (plus a $775 destination charge).
So, Harley's 121 cubic-inch V-twin isn't just the biggest in its lineup; it's likely the biggest engine among its cruiser and touring rivals, too. That said, as a quick look at its rivals shows, it's not the most powerful. When it comes to big touring bikes, Indian takes the crown for power, and Harley takes the crown for size.