Thanks to Ebay it is now possible for the average individual to stop dreaming and actually build their own custom motorcyle. The foundation of any motorcyle build is the frame.  Weekly, there are over 500 custom frames listed for sale within ebay.  It is my hope that this guide will help you sort through the Ebay listings and make an educated decision toward selecting and purchasing the foundation of your dream.

Current Frame listings

Frame Types:

• Hardtail:  Identified by the fact that there is no rear suspension, hence the term Hardtail.  The frame is loved by hardcore and old school enthusiasts alike.  This type frame is one of the more economical choices for a home build; a person does not have to puchase a rear suspension.  Also, the hardtail is not limited to budget builds.  The absence of a suspension system leaves room for creative metal fabrication that makes this bike a favorite on the show circuit.

A hardtail by the Martin Bros.

• Softail:  The softail was originally designed by Harley-Davidson to look like a hartail yet still utilize a rear suspension.  The softail frame is the foundation of Harley Davidsons's Fatboy and the Springer Classic.  This is the frame I personally use and recommed to coustomers.  It is available in many variations, all of which are less likely to destroy the rider's back.

A softail by Paramount Custom Cycles

• Fxr:  The FXR style frame was used on a number of stock Harley's.  This frame is characterized by its external rear suspension.  The FXR frame is extremely comfortable to ride.  This is the frame for touring cross country.  If a person were to ride a thousand miles on the FXR frame they would come to appreciate the FXR.  This frame, however, has not been overly popular as a custom bike foundation.  There are exceptions.  Ironhorse motorcycles and Big Dog motorcyles both build an Fxr "style" custom motorcycle.  Other unique features of the FXR style frame are the rubber isolate motor mounts and swing arm bushings.  These help to lessen the vibration of the drivetrain and provide superior handling.

An FXR frame by Daytec

Tire Size:

Fat's where it's AT.  Howerver, with the ever increasing popularity of large tire bikes, I feel that a warning is in order: all wide tire frames are not created equally.  It is possible to run a 200mm tire without any major driveline modification.  Anything larger than 200mm, i.e. 250 or 300mm rear tires require one of three driveline modifications.

• Drivetrain Offset:  The drivetrain offset involves shifting the engine, primary (the assembly that connects the engine and transmission), and transmission to the left, thereby creating alignment with the rear wheel.  This is an effective method for getting a big tire in frame and many pleased owners of custom fat tire motocycles are content running this setup.  I personally avoid the drivetrain offset.  By shifting the driveline, the center of balance is lost.  When I ride a bike like this it feels as if a strong wind is constantly blowing on the right side of the motorcyle.

• Transmission Offset:  To correct the center of gravity many companies build frames that only offset the transmission.  This is accomplished by moving only the transmission to the left and inserting a spacer between the primary and engine.  Even though this corrects the balance it creates a new and unique set of problems.  By spacing the primary away from the engine, mass is added to the rotation of the main shaft (crank).  This setup has been known to cause premature failure of both the engine main seal and the bottom end of the engine.  In response the this failure, manufacturers of primary components have created a bearing setup that aligns the main shaft to prevent further problems.  To me however, this means we have a correction-of a correction-of a problem.  Pay close attention when considering a wide tire frame.

• Right Side Drive:  The final possibility is by far the most recommended.  A right side drive (RSD) frame uses an RSD transmission.  This is a transmission that has had the drive pulley moved from the left side of the transmission to the right side of the transmission.  This combination will build a well balanced and reliable motorcyle.  The only drawback to the right side drive is the high cost.

Style:

The frame heavily influences the overall style of the motorcycle.  I feel no need to go into detail about stock modified styles because they are all based on stock frames.  Also, I will not elaborate on the growing trend of the old school style because it can be created on any type of frame.  There are three major styles of custom motorcyles: Chopper, Pro Street, and the newer Street Fighter.  You have to be careful when selecting a frame because as a foundation, it can limit your building possibilities.  If you buy a Chopper frame it is not feasible to build a Prostreet motorcyle, vice versa.  It is however, possible to build a Street Fighter style motorcyle on a modified Prostreet Frame.

• Chopper:  The chopper is built on a frame with stretched down tubes ( the frame rails connected to the neck running downward in front of the motor) and stretched backbone as compared to the shorter stofck harley frame.  It is my opinion that to achieve the chopper style bike, a person needs a frame with a minimum of 3 inches of stretch in the down tubes and at least 38 degress of neck rake.  The variations are limitless for stretch (backbone and downtubes), frame type, and tire size.  I should mention that a Chopper handles extremely differently than a stock motorcyle.  Choppers tend to be harder to control at low speeds yet quite stable at high speeds.  They also have a larger turning radius than the standard Harley.

Chopper Style by OCC           Captain America ChopperClone By Paughco

• Prostreet:  The Prostreet style can be described as long and low.  Prostreets have shorter ground clearance compared to many other bike styles.  Prostreet frames, typically, have stretch only in the backbone and often have an inch removed from the downtubes.  This allows the bike to be built long and low with the gas tank as close to the engine as possible.  These style bikes are very reminisent of drag bikes.  They look fast standing still.

Bourgets Pro Street Ultra Craft Pro Street

• Street Fighter:  Street Fighters are a rather new and exciting development in the custom motorcycle community.  It is the marriage of custom Harley style motocyles with sport bike engineering.  These bikes are short and easy to handle with less neck rake (in the range of 23-32 degrees).  Street Fighters typically have good ground clearance which creates a sportier and better cornering bike.  I have seen a number of these bikes built on modified FXR frames.  Custom Chrome sells a kit bike and carries an FXR frame that allows the layperson to build a bike of this nature.  For the most part, these bikes are built on a much more extensively modified custom frame and are not mass produced.  This leads to limited availability.  Because this is a newer movement in custom styling, it may be more difficult to locate frames.

 A Confederate Street Fighter

 Custom Chrome kit bike Street Fighter

Caution:

• I advise caution and encourage you to be leary of frames that come in primer or paint.  This is for two important reasons: the first being that you can't examine the welds and quality of the frame.  The second reason is that a large number of parts are going to be fitted to your motorcycle and you need to be able to do a complete mock up or test build of the bike to check for fit and alignment of your components.  This will be hard to do if you are worried about scratching paint.

• Make sure that the frame comes with an MSO (manufacturers statement of origin).  The MSO is absolutely critical to getting a motorcyle titled and registered.  It must be an original-not a copy.  Also make sure the frame was produced by a reputable builder.  Your state will probably frown on an MSO printed off of a cumputer by someone who in not listed as a manufacturer

Closing:

I appreciate your time and thank you for reading my guide.  I hope you have found this guide to be informative and have a better understanding of what you are looking for in a frame, and how to go about choosing what you realy want.  Please let me know if this guide was helpful, as I plan to write more custom motorcycle related guides and your input will send me in the right direction.

P.S.

As encouragement I would like to share a picture on my personal bike.  90% of the parts were purchased from ebay.

Specs:  The following components were purchased on ebay at deep discount.  I am a motorcyle dealer and still shop on ebay.

1. Frame:  Wild Cat Aluminum pro street, 4 inch back bone stretch, 1 inch removed frome down tubes, softail.
2. Engine:  Patrick Racing, billet heads, cases, cylinders, 11.5 to 1 CR, 650 lift cam.
3. Wheels:  Rc components.
4. Forks:  Arlen Ness
5. Hand controls:  Arlen Ness
6. Foot controls:  Rc components
7. Rear fender:  Jesse James
8. Exhaust:  Martin bros.
9. Transmission:  Baker 6 speed
10. Primary:  BDL 3 inch belt

 The Infamous Pro Street by FAT BACK CUSTOM