Stop Rules: Harley-Davidson Sportster S “Revolution”

Sportster S Custom

AC Calella Custom x Stop Rules customize a Sportster S… 

In 2021, Harley-Davidson introduced the Sportster S (RH1250S) — a seismic shift for the Sportster platform, which can trace its heritage back to 1957. Many of the characteristic Sportster elements are gone, replaced with modern tech and performance:

“What Harley-Davidson have presented us with now is a brand new bike, nay a brand new concept, that chucks all but the Sportster name in the bin. Following on from the Pan America, the Harley-Davidson Sportster S eschews air-cooling, non-existent electronics and ‘feel over performance’ in favour of modern engineering, less show and more go.” —MCN

Sportster S Custom

The S certainly does have more go.  The heart of the bike is the Revolution Max 1250T engine, a 120-bhp liquid-cooled 60-degree V-twin with DOHC and variable valve timing (VVT), which exhales via a 2-1-2 high-mounted flat track-inspired exhaust.  The 500-lb bike isn’t lacking is torque, with 92 lb-ft spread across a meaty midrange. The result is a bike that can compete with the likes of the Indian FTR, BMW R NineT, and Triumph Bobber.

Sportster S Custom

With the bike being so new, we’ve seen very few Sportster 1250 S customs so far. One of the first workshops to tear into one was Spain’s AC Calella Custom, who develops and manufactures H-D parts through their brand Stop Rules Motorcycles. Once they had their ’21 Sportster S in the shop, the vision was clear:

“Enhance the cafe racer style by giving the motorbike a racing bike essence with bold colours and large logos. The new parts are handcrafted to give the bike a sportier style.”

Sportster S Custom

They developed and fabricated a range of parts for the bike, including the front and rear fenders, front fairing, number plate holder, tail section / saddle, micro indicator brackets, and more — pieces available via

Sportster S Custom

They also reprogrammed the ECU to squeeze some extra ponies out of the Revolution V-twin, and painted the engine itself black for some extra attitude. The rest of the colorway is slightly reminiscent of the iconic Gulf liveries of yesteryear.

Below, we talk to JC Galan of Stop Rules for more details on the build.

Sportster 1250 S Custom: Builder Interview

Sportster S Custom

• Please tell us a bit about yourself, your history with motorcycles, and your workshop.

Before opening AC Calella Custom, I was involved in several jobs and businesses. First in the automobile sector, working for Mercedes Benz as one of the main salesmen of the company in Spain. Then in my own businesses such as vehicle import, owning a discotheque and restaurant, and wholesale trade.

Sportster S Custom

AC Calella Custom opened its doors in 2010, and in 2012 the decision was taken to specialise in Harley-Davidson. It is a family business, led by me but supported by my family. The idea to start this path arose simply because of my passion for motorbikes, the firm intention to show what was inside me in terms of ideas and proposals for the creation of unique motorcycles. I love riding motorbikes, and if they are beautiful and different from what we can see anywhere else, all the better.

Sportster S Custom

• What’s the make, model, and year of the donor bike?

Harley Davidson Sportster 1250 S from 2021.

Sportster S Custom

• Why was this bike built?

Mainly for promotion of our workshop AC Calella Custom and our brand Stop Rules, through which we manufacture and sell parts for Harley-Davidson motorbikes. As it is a new bike, we wanted to bet on this model, being one of the first builders to work with it.

Sportster S Custom

• What was the design concept and what influenced the build?

Enhance the cafe racer style by giving the motorbike a racing bike essence with bold colours and large logos. The new parts are handcrafted to give the bike a sportier style.

• What custom work was done to the bike?

Reprogramming of the engine to squeeze the maximum power out of it, painting of the engine in black to give character to the bike, fabrication of handmade parts such as the front mudguard, the mask, the rear mudguard, the number plate holder and the front micro indicator brackets. All these pieces can be found for sale on our website:

• Does the bike have a nickname?


Sportster S Custom

• Can you tell us what it’s like to ride this bike?

A new sensation for Harley-Davidson riders like us. It’s an extraordinary engine, with uncommon power and of course new technology that makes this beast a very reliable and safe bike.

Sportster S Custom

• Was there anything done during this build that you are particularly proud of?

Mainly design work on the concept of the parts, as well as the paint design and final aesthetics of the bike.

Sportster S Custom

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  1. Still looks like a boring Harley

  2. No Thanks!! It is UGLY!! All that the Sportster ever was is gone!! Look at that front tire!! What the Hell is that ? The Hindenburg? And lastly, it has evolved to a bike the HD mechanics at the old , and I mean old, local HD shops are going to be awhile learning how to work on this thing!! Never trusted HD to give much value for the products they sell and this makes that worse for me. They cost waaaaay too much and really don’t do much for this rider. Indian spanks the Hell out of their XR750 and this is what they come up with? They walked away from the flat tracking because the were upended by the upstart FTR 750? Liker a spoiled child in the playground walking away from his friends with his ball!! Waaa!!! Waaa!! Waaa!! A bunch of crybabies testing out their crap on us!! No thanks……………..

  3. It looks like an inflatable motorcycle.

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