Analysing the "Motorcycle Move"

 

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This short review paper has been written in order to complement my video review of Tyler Ferrell's "Stock Tour Swing" book and his supportive videos that are available at his golfsmartacdemy.com website.

Tyler Ferrell strongly endorses the golf intructional idea of using the "motorcycle move" (which some golf instructors call the"'reverse motorcycle move" or the "Dustin Johnson move") in the early-mid downswing in order to close the clubface relative to the clubhead arc by the delivery position (P5.5 - P6 position). He believes that if one closes the clubface (relative to the clubhead arc) by using the "motorcycle move" during the early-mid downswing, then it would be possible to simply rotate the body (pelvis and upper torso) to an open alignment by impact without having to use a rapid/late left forearm supinatory motion (called the release of PA#3 in TGM terminology) in order to square the clubface by impact. I believe that his opinion is wrongheaded and I analysed his opinions on the "motorcycle move" in my critical video at

Many other golf instructors also teach the "motorcycle move" and here is an example featuring one of Clay Ballard's golf instructors at TopSpeedGolf.

Top Speed Golf - Clay Ballard video - https://www.youtube.com/watch?v=430tFu9HnDU

Here are capture images of the golf instructor performing what he calls the ""Dustin Johnson move" in the early-mid downswing, but what he is demonstrating is really the "motorcycle move" and not the "*DJ-move" that Dustin Johnson actually performs in his downswing action.

(* I have described the "DJ-move" in another short review paper and it is available at DJMove.html )


 

Image 1 shows the golf instructor starting to actively palmar flex the left wrist when the club is still at the end-backswing position (P4 position). Note that it causes the clubface to become more horizontal relative to the ground, and also relative to the back of the left forearm, and it also causes the clubface to become more closed relative to the clubhead arc. What is causing the clubface to become more closed relative to the clubhead arc? I believe that it is primarily due to a finger torquing action secondary to activation of the finger flexor muscles (flexor digitorum profundus) that flex the left hand's 3rd, 4th and 5th fingers as they tightly grip the club handle in the palm of the left hand and that finger-torquing action causes the club handle to be twisted counterclockwise. Activation of those finger flexor muscles will cause the clubshaft to rotate counterclockwise due to a "finger torquing" action while the left wrist simultaneously becomes palmar flexed. In other words, the true cause of the clubface-closing phenomenon in the "motorcycle move" is the finger-torquing action and not the left wrist palmar flexion maneuver, which probably occurs secondary to the active contraction of the flexor profundus muscle (and not primarily due to contraction of the two wrist flexor muscles - flexor carpi ulnaris and flexor carpi radialis).

Note that the clubface becomes even more closed during the early-mid downswing so that it is significantly more closed (relative to the clubhead arc) by the P5.5 delivery position (image 3). What is causing the clubface to become even more closed between the P4 position and the P5.5 position? The one factor is the twistaway phenomenon - which is Brian Manzella's name for the clubface-closing phenomenon happening during the "motorcycle move's" finger torquing action - that is happening biomechanically secondary to activation of the finger flexor muscles, and which reaches its peak twistaway intensity during the P5.5 - P6 time period. The second biomechanical factor is the fact that he is increasingly supinating his left hand so so that it becomes more vertical (and less horizontal) between P5 (image 2) and P5.5 (image 3). Theoretically, left forearm supination during the P4 => P6 time period should cause a clubshaft-steepening action that is called a "tumble action", but that can only happen if the right arm/hand allows the "tumble action" phenomenon to happen by i) the right humerus becoming more internally rotated, ii) the right forearm becoming more pronated and iii) the right elbow staying back alongside the right shirt seam in a punch elbow position. If a golfer uses a pitch elbow motion during the P4 => P6 time period where the i) right humerus does not become internally rotated and ii) where the right forearm remains supinated and iii) where the right elbow leads the hands as the right elbow moves progressively down to its pitch location in front of the right hip area by P6, then the right palm will remain parallel to a progresively shallowing clubshaft swingplane. If the right palm is progressively shallowing during the P4 => P6 time period, then it resists any tendency of the clubshaft to steepen when the left forearm is actively supinating. In fact, any active/early left forearm supination will secondarily cause the left wrist to become passively palmar flexed if the clubshaft remains on a shallowing clubshaft swingplane because of the "holding back" action of the right arm/hand. While the golfer is actively trying to supinate the left forearm against the "holding-back" action performed by the right arm/hand, it is very likely that the golfer will be simultaneously gripping the club handle more tightly with the left hand so that it maximises the twistaway phenomenon happening during that same time period (when the left wrist is radially deviated).

Now, consider what happens during the P6 => impact (P7) time period by viewing these face-on capture images.


 

Image 1 is at address. Note that the golf instructor has adopted a neutral left hand grip. Note the position of the left lower forearm's radial bone (just above wrist level) relative to his left antecubital fossa (which is facing away from the target because the left humerus is internally rotated at address). The left lower forearm's radial bone is rotated slightly clockwise relative to the left antecubital fossa and that means that the left forearm is slightly pronated at address.

Image 2 is at the P6.5 position (in his simulated late downswing action). Note that his left wrist is still markedly palmar flexed and that causes the clubshaft to be angled backwards away from the target. Note that the clubface is somewhat closed relative to the clubhead arc, but still open relative to the ball-target line. Most importantly, note how much the left forearm has supinated between the P5.5 and P6.5 positions - note that the left forearm is slightly pronated (relative to the left antecubital fossa) at the P6.5 position and that means that it has actually supinated back to its address alignment even though the clubface has not yet reached impact.

Image 3 is at simulated impact (in his simulated late downswing action where he is exaggerating the degree of forward shaft lean by having a very palmar flexed left wrist alignment at simulated impact). Note that his clubface is square to the target. Most importantly, note that he had to supinate his left forearm even more between P6.5 and impact in order to get a square clubface at impact. In other words, the clubface-closing effect that happened during the early-mid down swing - secondary to a twistaway phenomenon - has dissipated in the late downswing as his left wrist becomes increasingly ulnar deviated and he still has to use more than the usual amount of left forearm supination during the P5.5 => P7 time period in order to get a square clubface by impact.

Image 4 is captured from his "real life" golf swing action that he performed at full speed. The frame rate of the video was too slow to capture the clubhead at the exact moment of impact, and this image is the first video frame immediately post-impact. Note that he has less left wrist bowing at impact (compared to his simulated impact alignment demonstration). Most importantly, note that his left forearm is significantly more supinated (relative to his left antecubital fossa) - when compared to his address alignment. That "fact" proves that the clubface-closing phenomenon seen in the early-mid downswing (due to the combination of a twistaway "finger torquing" maneuver combined with an early left forearm supination manuever) does not decrease the total amount of left forearm supination needed to get a square clubface by impact. In fact, if a golfer comes into impact with a greater degree of forward shaft lean due to having a bowed left wrist (as seen in Dustin Johnson's or Jon Rahm's golf swing actions), then it will actually require a greater amount of left forearm supination than usual in order to get a square clubface at impact. Having a clubface that is slightly more closed to the clubhead arc at the P6 position (due to the combined use of a "twistaway maneuver that is combined with an early left forearm supination maneuver" during the early-mid downswing) does not alter the fact that a golfer (who adopts a neutral left hand grip) is going to have to use the standard PA#3 release action (which is biomechanically due to left forearm supination) in the later downswing in order to get a square clubface by impact. The golf instructional "idea" that one can close the clubface during the early-mid downswing's P4 => P6 time period by bowing the left wrist, and that one can then simply rotate the body into impact between P6 => P7 while maintaining a bowed left wrist, without having to use a PA#3 release action in the later downswing in order to square the clubface, is a fallacy!

 

Jeff Mann.

March 2018.