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Post by imperfectgolfer on Dec 5, 2020 11:56:26 GMT -5
Here is Tyler Ferrell's video where he discusses the Motorcyle Move. I posted the following comment in his comment section (and it may not be visible if he has banned my comments from being publically visible). "Tyler, I think that you have got many facts wrong regarding your Motorcycle Move opinions. You seemingly believe that when a lead wrist flexion-graph shows a motion towards decreasing lead wrist extension (and in the direction of lead wrist flexion) during the early-mid downswing - as seen in your transition style graph - that the golfer must be applying the motorcycle move. That allows you to incorrectly label Henrik Stenson as using the motorcycle move between P4 => P6 because his lead wrist is less extended at P6 than it was at P4. However, Henrik's clubface does not close relative to his clubhead arc (or relative to the watchface area of his lead lower forearm) between P4 => P6 even though his lead wrist is becoming less extended - because he is using the intact LFFW/GFLW golf swing technique as described in the following review paper at perfectgolfswingreview.net/LeadWristBowing.html . The key point that you do not seemingly understand is the fact that the lead wrist will become more extended if the golfer uses an intact LFFW/GFLW golf swing technique as it becomes more radially deviated, and that it will become less extended as it becomes more ulnar deviated. Here is the image - perfectgolfswingreview.net/Author-BowingTwelve.jpg - showing that fact where the clubshaft remains straight-line-aligned with the lead arm and where the clubface does not close - as the author moves his lead wrist in the direction of either radial deviation, or ulnar deviation, while maintaining a GFLW (even though the degree of lead wrist dorsiflexion changes to a marked degree). You also incorrectly claim that it is possible to perform the motorcycle move to close the clubface relative to the clubhead arc after P6 and you use Rory Sabbatinni as an example. However, in that review paper, the author shows that lead wrist bowing after P6 (when the lead wrist becomes ulnar deviated) causes clubshaft angulation without any clubface closing. That means that bowing the lead wrist between P6 => P7 will cause forward shaft lean, but it will not close the clubface relative to the clubhead arc. In fact, the increased degree of forward shaft lean at impact (secondary to lead wrist bowing happening in the later downswing when the lead wrist increasingly ulnar-deviates) opens the clubface relative to the ball-target line and the golfer will need more (not less) lead forearm supination to get the clubface square by impact. You also seemingly believe that using the motorcycle move between P4 => P6, and even further to slightly beyond impact (as you demonstrate in your "continuing motorcycle move" video), will decrease the amount of lead forearm supination that is normally required between P6 => P7 in order to get a square clubface by impact. However, you fail to take into account the fact that the clubface closing benefit of ~20-25 degrees that is obtained by using the motorcycle move between P4 => P6 is offset by the clubface-opening effect of continuing to maintain a bowed lead wrist between P6 => P7, which causes the clubshaft to angle backwards away from the target. In that review paper, the author uses Collin Morikawa as an example, and he shows that Colin Morikawa comes into impact with a lot of forward shaft lean (where the hands are well ahead of the clubhead at impact). That opens the clubface relative to the ball-target line and that phenomenon necessitates more counterclockwise rotation of the lead hand in the later downswing. Finally, look at Jon Rahm's 3D lead forearm supination graph in that review paper, and note how much and how rapidly he has to supinate his lead forearm in his later downswing - even though he is a prototypical example of a golfer who uses the bowed lead wrist technique." Jeff.
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Post by dubiousgolfer on Dec 9, 2020 13:05:18 GMT -5
Dr Mann
Have you ever seen this short video by Jon Sinclair? This doesn't seem to be a pure 'reverse motorcycle move' but also active left and right forearm supination in the downswing.
I'm confused because JS reiterates this dual forearm supination in this video below at 25:16- 25:35 but I think he's making a mistake because the +y axis in Trail wrist graph is pronation, while +y axis in the Lead wrist graph is supination.
I've mentioned this before in a previous post about the reading of TPI graphs (unless I am completely mistaken). Has JS made some (unbelievable) basic error in the reading of TPI graphs and based his instruction on that error?
DG
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Post by imperfectgolfer on Dec 10, 2020 10:23:09 GMT -5
Dr Mann Have you ever seen this short video by Jon Sinclair? This doesn't seem to be a pure 'reverse motorcycle move' but also active left and right forearm supination in the downswing. I'm confused because JS reiterates this dual forearm supination in this video below at 25:16- 25:35 but I think he's making a mistake because the +y axis in Trail wrist graph is pronation, while +y axis in the Lead wrist graph is supination. I've mentioned this before in a previous post about the reading of TPI graphs (unless I am completely mistaken). Has JS made some (unbelievable) basic error in the reading of TPI graphs and based his instruction on that error? DG I agree with Jon that dual forearm supination happens in the downswing, and I do not believe that he is misinterpreting the trail forearm supination graph. Trail forearm supination happens in the earlier downswing between P4 => P5.5 as part of the clubshaft shallowing action, but it continues after P5.5 until just before impact (while the lead forearm supination phenomenon is happening). If the trail forearm did not continue to supinate between P5.5 => P6.5+, a golfer would be performing the "Malaska Move" where the trail palm does not stay under and slightly behind the club handle but where it gets more on top of the club handle with the trail palm facing the ground. Look at Dustin Johnson's late downswing. Note that his trail palm is facing partially skywards all the way between P5.5 => impact, which means that the trail forearm is still supinated. It only moves from being supinated to becoming more neutral as the trail forearm starts to pronate between image 3 and image 4, but that happens after P6.8.
Note that his lead forearm is supinating between image 1 and image 4. Here are face-on capture images. Note how much DJ's lead forearm is supinating between P6.5 (image 5) and impact (image 6). The trail forearm is still partially supinated during that time period. So, how does the trail palm get from being more under the club handle at P6.5 to getting to being more behind the club handle at impact, which needs a roll motion of the trail palm? I believe that the roll motion of the trail palm that is required happens due to trail wrist circumduction - where the trail wrist becomes less extended and also less radially deviated - and that allows the right palm to roll between P6.5 => P7 (without requiring a lot of trail forearm pronation).
Addendum added later:
Here is Tyler giving a presentation of Steve Elkington's lead wrist graphs.
Note that his lead forearm is supinating in his late downswing - representing a PA#3 release action.
Here is Elkington's trail forearm supination graph.
Note that his trail forearm is also supinating during the later downswing.
So, the phenomenon of dual forearm supination during the later downswing should not be deemed to be unusual.
Jeff.
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Post by imperfectgolfer on Dec 10, 2020 11:38:39 GMT -5
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Post by dubiousgolfer on Dec 10, 2020 19:22:58 GMT -5
Many thanks for your reply to my previous post.
I'm glad you were able to communicate your opinions to Tyler Ferrell.
DG
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Post by dubiousgolfer on Dec 11, 2020 7:37:40 GMT -5
Dr Mann With reference to TF's comment "On 3D, the pros have shown that to control the club face and create lag requires some amount of shaft twisting" Isn't there a possibility that the flexing of the lead wrist when moving into ulnar deviation could help create lag? The clubshaft becoming more angulated relative to the left arm creates a larger 'moment arm' (ie. ability to create a greater MOF later in the downswing)? DG The image below (although inaccurate from a 'Force' direction perspective ) provides an idea of what I meant above and 'moment arm' would be R1. Also, if the clubface is now more open relative to the ball-target line , plus the ability to apply more 'MOF' (because of the increased clubshaft angulation and 'moment arm' ) and create greater clubhead speed, wouldn't the clubface also need to be rotated quicker to square it by impact?
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Post by imperfectgolfer on Dec 11, 2020 10:25:12 GMT -5
DG,
You asked-: "Isn't there a possibility that the flexing of the lead wrist when moving into ulnar deviation could help create lag? The clubshaft becoming more angulated relative to the left arm creates a larger 'moment arm' (ie. ability to create a greater MOF later in the downswing)?"
If your definition of lag in the later downswing and at impact means that the hands are ahead of the clubhead, then lead wrist bowing when the lead wrist is ulnar deviated will definitely produce lag (forward shaft lean).
You also stated-: "Also, if the clubface is now more open relative to the ball-target line , plus the ability to apply more 'MOF' (because of the increased clubshaft angulation and 'moment arm' ) and create greater clubhead speed, wouldn't the clubface also need to be rotated quicker to square it by impact?"
I agree about needing to rotate the clubface quicker near impact - and that's my main argument about a likely high clubface ROC happening near impact in a golfer who has a lot of forward shaft lean at impact (like Collin Morikawa). However, I cannot understand how that moment arm can significantly increase clubhead speed at impact if the degree of clubshaft angulation does not change by a large amount between P6.8 => P7.2. Also, a negative torque phenomenon, where the peripheral clubshaft is bent forward between P6 => P7, is also present in a golfer who uses the bowed lead wrist technique - so theoretically the lead hand cannot be applying a positive torque near impact.
Jeff.
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Post by dubiousgolfer on Dec 13, 2020 9:30:47 GMT -5
Dr Mann
I was just clearing some old emails and found this one from Jon Sinclair (over a year ago). I didn't understand most of it at the time but now I can see the underlined part seems to match with your own findings (but he never offered a detailed explanation).
-------------------- The wrist are very complexed. You have to look at both to really determine how the club is being manipulated.
First of all a position in and of itself neither opens or closes the club face. So these players having flexed lead wrist does not mean they have closed the club. The grip has a lot to do with what is happening as well.
As a very general rule a player with a lot of flexion in their wrist at the top will actually start closing the club face later than one with a lot of extension. I am talking about world class players here. After club transition flexed players will tend to move toward extension a bit before going hard back to flexion.
I cannot think of a player off the top of my head that does not have less supination at impact than when they started. This is a tricky measurement though. AMM does not do the shoulder girdles so that can alter it some.
Moving toward flexion closes the club face at the top but then acts and opens it at impact. Pronation/Supination takes the in and out of plane until you get more ulnar deviation then lead supination/ trail pronation closes it.
I would need to do a complete study but I would doubt highly that there is less or more forearm movement in a flexed wrist over a extended one. If you are talking about higher or lower ROC I would also say that is a myth. It is what people want to believe. It fits nicely with a narrative.
------------------
DG
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Post by dubiousgolfer on May 28, 2023 4:30:08 GMT -5
Dr Mann I was just clearing some old emails and found this one from Jon Sinclair (over a year ago). I didn't understand most of it at the time but now I can see the underlined part seems to match with your own findings (but he never offered a detailed explanation). -------------------- The wrist are very complexed. You have to look at both to really determine how the club is being manipulated. First of all a position in and of itself neither opens or closes the club face. So these players having flexed lead wrist does not mean they have closed the club. The grip has a lot to do with what is happening as well. As a very general rule a player with a lot of flexion in their wrist at the top will actually start closing the club face later than one with a lot of extension. I am talking about world class players here. After club transition flexed players will tend to move toward extension a bit before going hard back to flexion. I cannot think of a player off the top of my head that does not have less supination at impact than when they started. This is a tricky measurement though. AMM does not do the shoulder girdles so that can alter it some. Moving toward flexion closes the club face at the top but then acts and opens it at impact. Pronation/Supination takes the in and out of plane until you get more ulnar deviation then lead supination/ trail pronation closes it.I would need to do a complete study but I would doubt highly that there is less or more forearm movement in a flexed wrist over a extended one. If you are talking about higher or lower ROC I would also say that is a myth. It is what people want to believe. It fits nicely with a narrative. ------------------ DG Dr Mann JS said: "Moving toward flexion closes the club face at the top but then acts and opens it at impact" So am I correct in assuming that JS is in agreement with your observation that ulnar deviation, while lead wrist is in flexion , acts to open the clubface to the ball target line approaching impact? I sometimes find his statements very difficult to understand like the following: "I cannot think of a player off the top of my head that does not have less supination at impact than when they started." Is he implying that virtually all players have more lead forearm supination at impact than at address? He also said the following: "As a very general rule a player with a lot of flexion in their wrist at the top will actually start closing the club face later than one with a lot of extension" "I would need to do a complete study but I would doubt highly that there is less or more forearm movement in a flexed wrist over a extended one"Doesn't this imply that a golfer with a bowed wrist will square the clubface later in the downswing when the clubhead is moving quicker? And doesn't this introduce a more difficult clubface squaring timing factor into the swing mechanics? DG
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Post by imperfectgolfer on May 28, 2023 8:05:43 GMT -5
Dr Mann I was just clearing some old emails and found this one from Jon Sinclair (over a year ago). I didn't understand most of it at the time but now I can see the underlined part seems to match with your own findings (but he never offered a detailed explanation). -------------------- The wrist are very complexed. You have to look at both to really determine how the club is being manipulated. First of all a position in and of itself neither opens or closes the club face. So these players having flexed lead wrist does not mean they have closed the club. The grip has a lot to do with what is happening as well. As a very general rule a player with a lot of flexion in their wrist at the top will actually start closing the club face later than one with a lot of extension. I am talking about world class players here. After club transition flexed players will tend to move toward extension a bit before going hard back to flexion. I cannot think of a player off the top of my head that does not have less supination at impact than when they started. This is a tricky measurement though. AMM does not do the shoulder girdles so that can alter it some. Moving toward flexion closes the club face at the top but then acts and opens it at impact. Pronation/Supination takes the in and out of plane until you get more ulnar deviation then lead supination/ trail pronation closes it.I would need to do a complete study but I would doubt highly that there is less or more forearm movement in a flexed wrist over a extended one. If you are talking about higher or lower ROC I would also say that is a myth. It is what people want to believe. It fits nicely with a narrative. ------------------ DG Dr Mann JS said: "Moving toward flexion closes the club face at the top but then acts and opens it at impact" So am I correct in assuming that JS is in agreement with your observation that ulnar deviation, while lead wrist is in flexion , acts to open the clubface to the ball target line approaching impact? I sometimes find his statements very difficult to understand like the following: "I cannot think of a player off the top of my head that does not have less supination at impact than when they started." Is he implying that virtually all players have more lead forearm supination at impact than at address? He also said the following: "As a very general rule a player with a lot of flexion in their wrist at the top will actually start closing the club face later than one with a lot of extension" "I would need to do a complete study but I would doubt highly that there is less or more forearm movement in a flexed wrist over a extended one"Doesn't this imply that a golfer with a bowed wrist will square the clubface later in the downswing when the clubhead is moving quicker? And doesn't this introduce a more difficult clubface squaring timing factor into the swing mechanics? DG I cannot rationally comment about JS's opinions because I cannot clearly understand what he is asserting. He can sometimes be very opaque when he talks about golf swing biomechanics. Jeff.
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