Convert Your Street Bike into a Cafe RacerDate:06-01-2017 Source:chinamotor
It was in the U.K. during the 1960s that a new style of motorcycle was born. Racing enthusiasts took their Triumphs and BSAs and added all sorts of racy-looking accessories and engine tuning components. Not content with a bike that just looked like a racer, the owners would often have impromptu races between the many cafés that dotted the English countryside.
The Café Racer Look
Although café racers come in many custom forms, there are some commonalities that run throughout the design. With the lowering of the handlebars and changing of the gas tank and seat, the outline of the bike becomes more curved. It is important that the café racer is not clumsy in appearance. With parts brought toward the center of the bike, the bike becomes more visually aggressive. The gas tank and “humpback” seat (described below) mirror each other, accentuating the curved look.
Today, for the owner-rider wanting to replicate the ’60s look of a café racer, the good news is that there are many over-the-counter parts for the most popular bikes. Adapting some of these café racer parts to fit any bike is not out of the question but may require some basic engineering.
Parts to be replaced include:
- Handlebars and levers
- Gas tank and seat
- Swept-back pipes and megaphones (reverse cone)
- Rearset footrests and levers
- Front fender
Ace bars were designed to be a compromise between racing clip-ons and the regular stock bars. Unlike pure racing machines, stock street bikes typically had their headlight mountings covering the top of the fork tubes where the clip-ons would be mounted. In addition, ace bars can be fitted to bikes where the original gas tank is being retained.
Fitting ace bars is a simple case of removing the old street bars and fitting the new bars using the stock mounting points. However, there can be a number of complications, namely the cables, which can be too long. Shorter aftermarket cables are available for the majority of applications or can be adapted to counter this problem. Of more concern are handlebars that have the electrical wires inside on the stock setup. The ace bars must not be drilled to create an opening for the wires, as this will greatly reduce their strength; it is better to replace the switches with ones that have the wires running on the top of the bars.
Tip: If the old grips are to be reused, the mechanic should use compressed air to lift the grips from the old bars (the left side only, as the right will come off with the throttle assembly).
The new ace bars should initially be fitted loosely to position them for rider comfort and gas tank clearance on full lock. Once the bars have been positioned, the retaining bolts should be torqued to the appropriate setting.
It is very important to check that the throttle cable is not being pulled as the bars are being rotated. This can be caused by poor routing or a cable that is too short. When the levers (brake and clutch) have been fitted, the mechanic should ensure that there is a small amount of free play on the clutch cable (approximately 1/8” or 3 mm).
Fitting a replacement fuel tank can be challenging, so unless you have extensive engineering experience, it is best to purchase a tank that is specific to your make and model. Luckily, there are tanks available for most of the popular machines currently being converted.
When replacing a tank, the mechanic must give due consideration to cable routing – this must be conducted at the same time as handlebar replacement, as the two have a major effect on the cable lengths.
Tip: It is very important to protect the fuel tank from vibration (especially on vertical-twins). Rubber mountings must be used wherever possible.
The original “humpback” seat on café racers was copied from the Manx Norton racers of the ’50s. An Internet search will easily locate many different suppliers of café racer seats, many of which come with mounting kits for a specific bike.
Tip: seats must be mounted securely. The seat must be supportive enough to spread the weight/load onto the bike’s frame. (Rubber blocks work well for this purpose.)
Pipes and Megaphones
Making the bike sound louder was all the rage in the ‘60s. To meet the street rider’s demands for louder exhaust systems and to try to stay within the law, manufacturers produced the reverse cone megaphone. These mufflers are available in most sizes to give your bike the classic café racer look and are generally a bolt-on accessory.
For some modern street bikes, swept-back pipes are available. They were originally fitted to improve engine performance and to increase ground clearance at full lean. Wherever possible, the original mountings should be used. This is particularly important with the megaphones, as they will tend to vibrate and cause stress on their mounting brackets. As a result, they should be mounted high for increased ground clearance.
Footrests and Levers
A number of aftermarket parts suppliers have adjustable rearset footrest kits that are ideal for café racer conversions. A visit to your local motorcycle dealer’s parts department should help to procure these.
In a number of cases, inverting the gear change lever will place it close to the position required with rearsets; however, a quality rearset kit will come with new levers that are correctly spaced.
When buying rearset kits, consider the rear brake light switch location, as the stock switch may not work. Luckily, switch kits are inexpensive and easy to fit.
Tip: The mechanic should try to position the gear lever so that the rider’s foot rests squarely in the middle when seated in his or her normal riding position. The brake lever should be mounted slightly lower than the rider’s foot, as he will sit up under braking, which lowers the foot.
The original front fenders of choice for the ’60s café racers were made of aluminum. These fenders are still available from most classic motorcycle parts suppliers. An alternative is to fit a fiberglass or carbon fiber front fender (fiberglass fenders are generally light, easy to fit, and less expensive than the aluminum alternative). Basically, the café racer fender is a shorter, lower profile counterpart.
By changing these six main components and following the guidelines for café racer style, you can create a bike that is both in the café racer style and completely original.