What exactly is a chopper? The definition is fairly flexible, varying from one region to another, but in general, a chopper is a customized motorcycle free of anything that isn't required to make it
go -- from windshields and mirrors to front brakes and speedometers.The history of the chopper begins shortly after World War II. Veterans sought out motorcycles like the ones they saw or drove during the war -- they'd buy a bike and then modify it to make it more like the ones they used to ride. Many of them removed the front fender from the bikes. The rear fender often came in two pieces -- the soldiers removed the rearmost section. They called the new, shorter fenders "bobbed" fenders, and so people who rode bikes with these sorts of modifications were called bobbers.
Later, builders began to make more radical changes to bikes. Many would strip it down to the frame and rebuild it piece by piece. They even began to fabricate parts like custom exhaust pipes or gas tanks to make their own bike a truly unique ride. Some began to call these bikes "choppers," because the owner had chopped up an existing bike to create something new.
Movies like "The Wild One" and "Easy Rider" brought choppers to the public's attention. The 1960s and 70s saw a new generation of chopper enthusiasts. Bikers spent weeks or months trying to create the perfect ride, whether it was designed for comfort, touring, speed or simply to make jaws drop.
In the 1980s, motorcycle companies like Harley-Davidson began to offer what they called custom bikes -- mass-manufactured motorcycles based off the most popular chopper designs. Coupled with an economic recession, this move nearly made chopper culture go extinct. It was only in the mid-'90s that custom bike shops began to flourish again, and today the culture is as strong as it ever was.
Later, builders began to make more radical changes to bikes. Many would strip it down to the frame and rebuild it piece by piece. They even began to fabricate parts like custom exhaust pipes or gas tanks to make their own bike a truly unique ride. Some began to call these bikes "choppers," because the owner had chopped up an existing bike to create something new.
Movies like "The Wild One" and "Easy Rider" brought choppers to the public's attention. The 1960s and 70s saw a new generation of chopper enthusiasts. Bikers spent weeks or months trying to create the perfect ride, whether it was designed for comfort, touring, speed or simply to make jaws drop.
In the 1980s, motorcycle companies like Harley-Davidson began to offer what they called custom bikes -- mass-manufactured motorcycles based off the most popular chopper designs. Coupled with an economic recession, this move nearly made chopper culture go extinct. It was only in the mid-'90s that custom bike shops began to flourish again, and today the culture is as strong as it ever was.
Chopper Rake and Trail
Whether you're using a hard-tail or soft-tail, one of the most pivotal decisions you'll make regarding your bike has to do with the bike's rake and trail. You may have seen some choppers that look really stretched out, with the front wheel sitting far out in front of the bike's frame. Bikers can get this kind of look by adjusting the rake of the bike. The rake is the angle formed between the neck on the frame of a bike and a vertical line. The bigger the angle, the further out the front wheel will be from the frame.
The distance between the point where the tire makes contact with the ground and a vertical line from the center of the front wheel's steering axis to the ground is the bike's trail. Trail is measured in inches, and in motorcycles should always be a positive number -- a negative trail means an unstable ride. Trail is important -- too little or too much trail and the bike will be sluggish or even impossible to control. Bike experts all have different opinions on what's the ideal trail length, but it tends to range between 3.5 and 6 inches.
While there's a relationship between a bike's rake and its trail, it's not always obvious. In most cases, increasing the rake of a bike's frame will increase positive trail, though this depends on what kind of fork assembly you use. In order to increase the rake of a bike without making the trail too large, some bikers use raked trees. Trees mount the fork assembly to the neck of the frame and usually have two sets of mounting brackets of equal length. A raked tree's brackets are at two different lengths, allowing the builder to set his fork assembly at a different angle than that of the frame's neck to the vertical.
Once you've got your frame and rake set, it's time to start looking at what you're going to mount on this monster. The world of choppers is full of options, so no two bikes are going to be the same. Chopper builders need to consider how the various parts are going to fit together, whether they'll need to offset components and how it will affect the bike's performance and balance.
While there's a relationship between a bike's rake and its trail, it's not always obvious. In most cases, increasing the rake of a bike's frame will increase positive trail, though this depends on what kind of fork assembly you use. In order to increase the rake of a bike without making the trail too large, some bikers use raked trees. Trees mount the fork assembly to the neck of the frame and usually have two sets of mounting brackets of equal length. A raked tree's brackets are at two different lengths, allowing the builder to set his fork assembly at a different angle than that of the frame's neck to the vertical.
Once you've got your frame and rake set, it's time to start looking at what you're going to mount on this monster. The world of choppers is full of options, so no two bikes are going to be the same. Chopper builders need to consider how the various parts are going to fit together, whether they'll need to offset components and how it will affect the bike's performance and balance.
Chopper Engines
Bike builders have a lot of choices when it comes to engines and how to mount them. Engines come with names like Evo, Twin Cam, Shovelhead, Panhead and Knucklehead. Some engines work better with certain frames -- in fact, some frames are designed specifically to hold a particular engine. Builders have to be aware of an engine's dimensions to make sure they have the right amount of clearance in their frame once they've installed all their components.
Some builders prefer to mount their engines directly to the frame of the bike as part of the "less is more" philosophy the chopper seems to embody. Engines like Harley-Davidson's Twin Cam 88B come with counter-balancers, which help reduce vibration, making it ideal for those who want to mount the engine directly to the frame. Engines without a counter-balancer system can give off a lot of vibration, so if you mount the engine directly to the frame, all that vibration will affect your ride, making it much less comfortable.
Many builders choose engines based on the look they are going for. Someone building a chopper designed as a throwback to the classic choppers of the '60s will want an engine that looks like an old one. He or she can either purchase an old engine and do some work on it, rebuilding it if necessary, or buy a new engine designed to look like the classic engines of the past. New Shovelhead engines look much the same as they did back in the '60s, but today offer bikers choices in everything from the compression ratio and camshaft to an electronic ignition.
Unlike most car engines, a bike engine's appearance is everything. That's because most choppers don't cover up the engine -- it's on full display. Harley-Davidson offers engines in black and chrome, for example, which usually increases the cost of the engine by about $1,000 over the less flashy aluminum versions.
Many builders choose engines based on the look they are going for. Someone building a chopper designed as a throwback to the classic choppers of the '60s will want an engine that looks like an old one. He or she can either purchase an old engine and do some work on it, rebuilding it if necessary, or buy a new engine designed to look like the classic engines of the past. New Shovelhead engines look much the same as they did back in the '60s, but today offer bikers choices in everything from the compression ratio and camshaft to an electronic ignition.
Unlike most car engines, a bike engine's appearance is everything. That's because most choppers don't cover up the engine -- it's on full display. Harley-Davidson offers engines in black and chrome, for example, which usually increases the cost of the engine by about $1,000 over the less flashy aluminum versions.
Chopper Brakes A chopper's brakes run on a hydraulic system -- builders can choose between disc brakes and drum brakes. Some bike builders leave off brakes on the front tire-- they say that the back of the bike carries so much weight that you don't need brakes up front. Many others say that all bikes need brakes both on the front and back of the bike, and that when you hit the brakes the weight of a bike transfers forward, increasing the risk of an accident. |
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