Knowing Rake and trail is huge in the build of a custom bike. Basically your rake would be the angle of your steering neck. A stock Harley Davidson has any were from a 28 degree rake to a 34 degree rake. What makes a Chopper motorcycle a chopper? The rake. Increasing your rake any more then 39 degrees in my eyes is a chopper. Choppers typically run a 40 to 50 degree rake. This gives your chopper that highly desired low and long look. The trail is the distance from the steering axis to the axle. This is very important when building a chopper. If your trail is to long you will have serious problems in the handling of your chopper. If the trail is over done the front end will be very heavy and flop when steering. Not to mention at high speeds you will have a front end wobble. If you have to little trail your bike will wobble, and if you have to much trail your front end will be very heavy to turn.How do I prevent this from happening? There is a general rule of thumb to go by when setting up your bikes front suspension. The motorcycles trail should be between 1.5 to 5 inches. So if you want a very aggressive look and don’t mind the heavy front end, go with a long trail. If you want a very easy bike to ride and don’t mind being the average everyday rider bike, go with a shorter trail.