Compression Breaking: Yamaha RX-1
Dear Ralph:
I own a Yamaha RX-1. My problem is I don’t like the abrupt deceleration that occurs when I cut the throttle. If I’m standing or in a slight crouch when I decelerate, it nearly pitches me over the handlebars. A second or two later, the machine seems to coast or freewheel, actually picking up speed. I have talked to Yamaha owners with other models that do the same thing. Is there any cure?
Sam
What you’re experiencing is known as engine compression braking, the abrupt slow-down right after you cut the throttle, followed by the clutch releasing the drive belt which gives you the coasting, or picking up speed, feeling.
One effective cure for this is to install lighter clutch weights with an aggressive shift curve. The aggressive shift curve will maintain or improve your acceleration and help to nearly eliminate the engine compression braking. Being that the lighter weights release the belt quicker, this means they are back shifting faster allowing you to accelerate quicker when you get back on the gas.
Many Yamaha tuners use the “Heavy Hitter†flyweights for this job. The Heavy Hitters will be set up at a stunning 56 grams of total mass instead of the (stock) 72 grams that Yamaha uses, but with an aggressive profile that compensates for the lighter mass. This will give you faster acceleration and back shifting, and surprisingly maintain the desired shift RPM. Contact Thunder Products (320-597-2700) www.thunderproducts.com and they can send you a set of weights dialed in for your weight and particular sled.