The Harley-Davidson Twin Cam 88 engine was released for the 1999 model year in September of 1998. Although this engine was a successor to the Evolution engine ("Evo"), it shares a number of characteristics with nearly all previous Harley-Davidson engines including the evo. It has two cyclinders in a V-twin configuration at 45 degrees. It's air cooled. It controls valve timing with push-rods. The crankshaft has a single pin with a tongue and fork arrangement for the connection rods. These are sandwiched between a pair of flywheels.
88B Engine
The Twin Cam wasn't initially used in the Softail model family before the year 2000. This was due to the chassis' design and issues with increased vibration. The increase in vibration was a result of the direct mounting of the engine to the frame. Dyna models are "rubber mounted" and therefore do not suffer the same vibration problems. Harley then solved the issue by making a redesigned version of the Twin Cam, the Twin Cam 88B, which is essentially the same as the original Twin Cam, but with a different engine block design and twin chain-driven counter-balancers, which had caused some controversy among Harley veterans, claiming that the "Harley vibes" were a part of their motorcycles. This engine is currently used on all softail models.
The Twin Cam generated considerably more power and torque than the Evolution Engine. All components were also built to tougher standards. Upgrading to 1550 cc became the norm among most enthusiasts.
When the Twin Cam engine was released, Harley-Davidson put much emphasis on the supposedly stronger case and bottom end. They claimed the older Big Twin design, with the cam bearing positioned directly above the main bearing on the right side of the engine, precluded increasing main bearing size to optimal and created structural weakness in the right side case because of the small space between the two bearings. However, after market companies have successfully used the old design in engines displacing 144 cubic inches (2360 cc) and more, producing well over 120 foot pounds (163 Nm) of torque and 120 horsepower (89 kW) without case failure, casting doubt on Harley-Davidson's claims.
When the Evolution Big Twin engine was released, Harley-Davidson did not protect its design elements as thoroughly as they have with the Twin Cam. In fact, H-D relied on the third-party firms to add value to their products and broaden their appeal. Since the Evo's release in 1984, though, the company has moved to catalogue thousands of accessories, including engine upgrades. The company moved to the Twin Cam not because the Evo had reached its power limits as a design, but because H-D could not prevent other manufacturers from making virtual clones of the design [citation needed]. With the Twin Cam, H-D was able to preempt cloning via the U.S. Patent Office, thereby making it a lot more difficult and expensive for the after market to compete with the Motor Co. in the development and sale of upgrades or complete motors.
88B Engine
The Twin Cam wasn't initially used in the Softail model family before the year 2000. This was due to the chassis' design and issues with increased vibration. The increase in vibration was a result of the direct mounting of the engine to the frame. Dyna models are "rubber mounted" and therefore do not suffer the same vibration problems. Harley then solved the issue by making a redesigned version of the Twin Cam, the Twin Cam 88B, which is essentially the same as the original Twin Cam, but with a different engine block design and twin chain-driven counter-balancers, which had caused some controversy among Harley veterans, claiming that the "Harley vibes" were a part of their motorcycles. This engine is currently used on all softail models.
The Twin Cam generated considerably more power and torque than the Evolution Engine. All components were also built to tougher standards. Upgrading to 1550 cc became the norm among most enthusiasts.
When the Twin Cam engine was released, Harley-Davidson put much emphasis on the supposedly stronger case and bottom end. They claimed the older Big Twin design, with the cam bearing positioned directly above the main bearing on the right side of the engine, precluded increasing main bearing size to optimal and created structural weakness in the right side case because of the small space between the two bearings. However, after market companies have successfully used the old design in engines displacing 144 cubic inches (2360 cc) and more, producing well over 120 foot pounds (163 Nm) of torque and 120 horsepower (89 kW) without case failure, casting doubt on Harley-Davidson's claims.
When the Evolution Big Twin engine was released, Harley-Davidson did not protect its design elements as thoroughly as they have with the Twin Cam. In fact, H-D relied on the third-party firms to add value to their products and broaden their appeal. Since the Evo's release in 1984, though, the company has moved to catalogue thousands of accessories, including engine upgrades. The company moved to the Twin Cam not because the Evo had reached its power limits as a design, but because H-D could not prevent other manufacturers from making virtual clones of the design [citation needed]. With the Twin Cam, H-D was able to preempt cloning via the U.S. Patent Office, thereby making it a lot more difficult and expensive for the after market to compete with the Motor Co. in the development and sale of upgrades or complete motors.
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