When it comes to increasing performance, the best bang for the buck is installation of gear drive cams. So today we are going to cover why GDC’s (gear drive cams) should be considered not only for performance upgrades, but safety upgrades as well. K and G Cycles (www.kandgcycles.com) goal is to educate you on GDC’s and what you can expect from them. So sit back, take some notes, and get ready to order up GDC’s for your bike.
A stock Harley is fairly respectable when it comes to performance numbers and seat of the pants feel. For those of you looking to harness more power from that motor, upgrading to GDC’s with a performance grind (a lobe grind designed to manipulate intake and exhaust timing) is the most economical choice in terms of parts and labor. I know many of you are saying, wouldn’t a big bore be the better choice? Yes and no. If you are looking for the best return on your $$$, GDC’s produce the largest gains in horsepower and torque with the least amount of labor associated with the installation. Aside from reducing the number of failure prone parts, GDC’s operate more efficiently. On a chain drive you have spring loaded tensioners that keep your chain from having slack, and these tensioners add friction to the cam drive itself. Two large plastic type feet press down on the chain from opposing directions, and this additional friction is rumored to rob your bike of 3-4 HP alone v/s GDC’s. Another big benefit of a gear drive cam combination is your timing stays accurate because there is no slop. Chain drive cams can vary as much as four degree’s in cam timing back and for as the engine is running. This lack of accurate valve timing is also a performance issue on the chain setup. One final and noteable difference is the wear factor. On a gear driven cam assembly there really isn’t a wear point like on a chain. The adjusters on the chain drive can and will eventually wear out. In the process, they have been known to break apart and travel into the motor and oil pump causing catastrophic damage.
Overall, Gear Drive Cams are a great performance addition to any motorcycle. Factoring in they are also a reliability improvement, they are a win win upgrade. At K and G cycles (www.kandgcycles.com) we love performance enhancing products, especially from S&S, Andrews, Crane , and so on. We love them even more when they also provide a service to us. Removing the weakest part of the Twin Cam motor and replacing it with a tougher design with proven power increases is what it’s all about.