Q: What are some guidelines for optimum performance when matching an aftermarket air intake with either a stock H-D or other aftermarket carb on the Twin Cam?Our Friends over at Wimmer Custom Cycles had this to Say: Most important is maintaining the correct air to fuel ratio. Keeping in mind more air more fuel…more power. Air flow charts are helpful and we provide them with all our intakes. In many cases the intakes will flow more air than is required, however as long as you provide enough fuel you will make more horsepower without hurting the engine. Some times we need to restrict air flow as the motor simply can not handle more than a certain amount. In almost all cases stock setups are very restrictive. The most important thing to do is check the plugs after making these changes. Or of course if you are able to have the motor dyno tuned this is by far the most accurate. But the average guy can check his plugs very easy and make sure they are a nice light gray color. If they are too white you are running too lean and need more fuel. If they are too black there is too much fuel and not enough air. Remember it is far better to be too rich than too lean. Running too lean will result in engine damage and discoloration of pipes for sure.
Q: If I put a stage one air cleaner on my 2009 harley dyna fxdc, do I need to reset computer?
A: Not necessary. Install the air cleaner assembly and go for a ride. If the bike runs good, performance is acceptable; it will not be nessacary to address your ecm. If you already have an exhaust, other than stock, you may not be so lucky.However, unless you are installing the air cleaner assembly, only, for aesthetics; You are defeating the purpose of the performance upgrade. If you introduce more air, you have to add more fuel. These bikes are relatively lean when they are stock. If you are in the market for a tuner, check out Vance & Hines FP3