I've done this on four gas engines using a HS-225 Mini servo with no problems. I make a arm out of 3/4" wide K&S brass strip. I drill a 3/16" hole that fits over the shaft, a 1/8" hole for a short bolt to lock the brass strip to the short choke arm and another smaller hole about 3/4" from the shaft to bolt a swivel ball link for the control arm to the servo. The choke shaft projects above the choke arm enough to keep the new arm in place. The brass is cut with tin snips and holes drilled to give smoth operation. I use the retract channel to operate the choke. I leave the detent in place, the servo dosen't have a problem with it.
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