01. Engine & Exhaust

Engine
The LC4 690 cc single-cylinder engine combines powerful acceleration from the very lowest revs with an outstanding free-revving nature and refined engine running. Another big plus is besides the engine being extremely economical with fuel it also has long service intervals of 10,000 km, keeping running costs low.


Cylinder head
A lightweight, compact cylinder head contains four valves and a single camshaft placed over the intake valves, and a secondary balancer shaft driven by the timing chain. The intake valves are actuated by finger followers and the exhaust valves by a rocker arm.


Balancer shaft
Twin balancer shafts, one in front of the crankshaft and the other in the cylinder head reduce vibration, which ensures a smoother ride.


Conrods
Plain bearings are used in the conrod to ensure a reduced reciprocating mass, which helps the engine run smoother and therefore enhances its lively character.


PASC clutch
The PASC (Power Assist Clutch) ensures the rider needs minimal input to operate it, due to reduced engine torque transferring to the clutch plates. The slipper clutch prevents rear wheel lock-up under aggressive downshifting, which reduces destabilizing rear wheel chatter on the tarmac when braking sharply or decelerating into turns.


Transmission
The smooth 6-speed gearbox with Quickshifter+ allows quicker clutchless up and downshifts when you're on the gas in and out of turns. This not only enables the rider to be more in control of the motorcycle by keeping a full grip of the handlebars, but also improves rear-wheel traction.


Ride-by-wire
The KTM 690 SMC R is equipped a ride-by-wire system, which processes throttle twist grip movements with the help of electronic sensors and activates the throttle valves to control throttle action. This significantly improves the response, giving the rider better throttle control of the potent single-cylinder and a smoother ride.


Injection / Engine Management
Electronic fuel injection and engine management allow performance perfectly suited to the riding conditions. The result: even more and even better controlled power, lower fuel consumption, and less emissions, plus the benefit of features like MTC (Motorcycle Traction Control), MSR (Motor slip regulation), and Quickshifter+. The rider has the choice between two different mappings to influence the engine characteristics. A twin-plug ignition system controls two differently sized spark plugs in the cylinder head independently from each other, for more efficient combustion and a smoother, precisely controlled combustion sequence at all times.


Exhaust
The exhaust system is made using high-quality stainless steel. It's routed as close as possible to the bike to help with the slim profile, and the exhaust shape has been optimized for hard offroad usage. For 2021, the KTM 690 SMC R has some additional hardware, this comes in the form of a new specification of catalytic converter in the muffler.


Airbox
Accessing the airfilter for maintenance is easy thanks to the airbox being located under the seat. This makes servicing the bike simple, and stress free, at the end of a long day's ride.
