Now that Kyosho has released the RB6.6, I have installed the official standup 3 gear standup transmission in my SC6. Unlike the 3D printed versions, this one is smooth and quiet. Here is a list of parts needed:
UM734
UM735
You can harvest the rest of the components from your standup 4 gear transmission. I plan to hit the track next week and enjoy the fit and finish of an OEM part. I am sure the car will drive similar to any car with a standup 3 gear.
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