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Old 01-01-2007, 07:02 PM
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AdrianM
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Originally Posted by hckeyplayer74
hey i was running over at the track near my house with my new 007 that i got from christmas and everything was running fine. well it than started making a chatter noise when i turn the steering wheel all the way and its a full throttle i checked everything it's not the dog bones. has this happened to anyone else and if so i need help it only happens when i turn the wheel all the way when it's going straight its fine. thanks alot
Dan

Xray007
Chatter is a normal part of running a spool on a sedan. To varying degrees all sedans chatter. Its worse when they are new and the CVD have very little play in them. As your CVD’s break in the chatter will mostly disappear.

The reason for this chatter is that what we call CVD's are not really Constant Velocity Drives. They are just fancy rebuild able universal joints.

The chatter comes from an acceleration and deceleration of the axles that is an inherent flaw in the way universal joints function. When the wheels are straight you have no problem but as you turn the wheels every 180 degrees the axle goes from being in line with the dog bone to being as much as 7 degrees ahead of the dog bone (at full wheel lock) and back to inline with the dog bone. This acceleration and deceleration of the axle and wheel causes the chatter.

You won't notice the chatter with a diff or a one way because they absorb the oscillation.

FYI, if you take the front wheels off and turn lock to lock you will notice the chatter is gone or greatly reduced. The reason for this is that the mass of the wheel and tire wants to keep rotating at a constant speed and fights the acceleration and deceleration of the axles. This causes the chatter.

Right now Losi is the only manufacturer with a true CVD in production. Schumacher and Hudy have true CVD’s in testing but they are not out yet.
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