The full kit consists of a FORGED piston 83.5mm+Rings, a honed cylinder paired with this individual piston and a full gasket set.
We also throw in a set of aluminum swing arm bearing plugs. The gasket set includes one foot gasket, one metal head gasket and one exhaust gasket (copper ring).
This dyno chart shows the possibilities in terms of torque and RWHP (rear wheel horse power). With the concurrent use of a free flow exhaust and air filter as well as a well tuned ECU up to 27 RWHP have been reached with this set alone. With an additional performance camshaft (HT-b cam) the output rose to almost 30 RWHP which is equivalent to about 34 HP as Royal Enfield measures it (BHP – measured at the crank).
We have produced a “how to” video available on YouTube which shows the entire procedure how to change the piston/cylinder combo.
Please read the FAQ dedicated to the 477 engine upgrade.