Bullet Engine

Royal Enfield Bullet Engine

UCE ENGINE

AVL ENGINE

UCE 

CI ENGINE

The 350 cc single cylinder air cooled unit found on the bullet is a legend which has been in the market for around 50 years. The engine had undergone a make over by an Austrian company AVL which made modifications to the engine to improve its performance.

The improvements made by the AVL company were not enough to give the BULLET a rebirth, the problem from the older CI engine persisted in the AVL as well. It was very essential for ROYAL ENFIELD to take step to prevent this drowning Brand. 2007 the Royal Enfield re launched the Iconic Bullet with the all new UCE engine

Unit Construction engine (UCE) was all new but had the DNA of the BULLET. The engine looked mature, premium and well-Engineered. Blend of technology and vintage looks was perfect. It made every Royal enfield enthusiast heart pump up.

In the UCE engine The engine, gearbox and clutch cases were three different units altogether connected to each other independently. So what happened was you needed to change oil at three places each time. Now, that is a messy thing to do, and also considering the various gaskets that required replacement frequently, in simple terms, it was maintenance heavy.

 The engine was separate from the gearbox and the clutch, a lot of power used to get lost in terms of transmission losses as the set up is not as efficient as modern engines. so, not only were the Cast Iron and AVL LB Bullets delivering lesser mileage but they were also making lesser power at the rear wheel even though they were making decent power at the crank shaft. The Cast Iron and AVL 350cc engines both produced 18 Bhp at the crank, but this figure went down to 12 Bhp at the rear wheel. Power loss: A whopping 33%. Culprit: Transmission losses.

UCE 350cc engine produces about 19.8 Bhp at the crank shaft. At the rear wheel, the power is about 16 Bhp. So, that is only 20% power lost in transmission losses, which while still a lot in terms of modern motorcycles, is fair enough for a Royal Enfield.The Unit Construction Engine is more fuel efficient than both the Cast Iron and AVL Lean Burn engine by almost 20%. While the 350cc CI and AVL engines used to deliver 30 kmpl, the UCE engine consistently returns 40 kmpl.