The Honda Rebel is a 250cc class motorcycle produced intermittently by Honda since 1985. Its light weight (just over 300 pounds) and smooth five speed transmission make the bike easy to ride. The Rebel's classic cruiser styling and chrome highlights give it the appearance of a much larger bike. Perhaps this is why so many owners seek to boost its horsepower. At 14.3 cubic inches, the engine only produces 16 to 17 horsepower. While the following procedures may produce more power and speed, don not expect gains of much more than two or three horsepower or a top speed over 85 mph.
Change the pilot jet in the carburetor from stock No. 35 to No. 38. Increase the main jet from No. 110 to No. 115. This can produce a gain of up to 15 percent, or 2.4 horsepower, which increases top speed by about 5 mph.
Tighten the valves to increase lift and duration, thereby increasing power. Their factory settings provide optimum performance, but they may have worked themselves loose.
Advance the timing two or three degrees and use a higher octane gas. If engine pinging occurs, back the timing off.
Replace the rear sprocket which has 33 teeth with one that has 30 or 31. This is a source of endless debate in Rebel Internet forums. Some advise replacing the front sprocket. Some say both, while others say replacement is pointless. The issue is whether such changes increase speed, or whether they reduce ability to reach the upper end of rpm where the most power is generated.
Items you will need
- Carburetor pilot jet, No. 38
- Carburetor main jet, No. 115
- Rear sprocket, 30- or 31-tooth
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