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Harley-Davidson Sportster 1250cc Conversion Kit

New Harley-Davidson Sportster XL Big Bore 1250cc Conversion Kit

Attention Sportsteristas!

There’s a new player in the Sportster big bore game. S&S Cycle’s new big bore Sportster conversion kit will bump up your 883cc up to 1,250.

Obviously there were always other options out there in the past. Riders are no longer limited between the Wiseco, Revolution Performance, Buell, or Harley-Davidson parts to kit up their 883cc Sportsters.

The S&S Cycle Sportster big bore conversion kit is good for Sportsters from 1986 through to 2014. In other words, it’s made to work with all evolution engines.

Harley-Davidson Sportster 1250cc Conversion Kit Dyno Chart

Performance changes are dramatic.

Within the same engine rev range (under 6,000 rpm), max torque increased from 47.3 to over 80, and max horsepower increased to over 90.

Performance further increases past 6,000 rpm, but lets be honest, that’s not the Sportster’s happy place. You can find out more info on S&S Cycle’s web page, here.

If you’re only looking for small performance increases rather than big gains, you can check out our post on how to stage 1 kit your Harley-Davidson Sportster.

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