Fit Question

This forum is for topics related to pro shop operation and bowling center maintenance.
Usual topics include: shop gear, fitting, drilling and lane maintenance.

Moderator: Moderators

Post Reply
User avatar
deanchamp
Trusted Source
Trusted Source
Posts: 455
Joined: August 4th, 2010, 10:23 am
THS Average: 220
Location: Melbourne, Australia

Fit Question

Post by deanchamp »

Hi all, I have just rechecked my grip as it had been nearly 3 years, and when going through the process a question arises that I don't recall seeing the answer to.

Using the Morich fitting system, my recommended fit is:

Thumb Pitch
7/16” Reverse (90 degree ave tight + 1/8" reverse for long thumb)
1/8” Left

Middle Finger
Middle Finger Span – 4 5/8”
Linear – 1/8” Reverse
Lateral – 3/8” Left

Ring Finger
Ring Finger Span – 4 3/8"
Linear – 1/8” Reverse
Lateral – 1/2” Right

Which is similar to what I've been using, except I've had 1/4" fwd in my thumb for years, so I reduce the span to compensate.

BUT as the linear finger pitch is determined from the thumb pitch, should I base my finger pitches off the thumb pitch I actually use, or the thumb I am recommend to use?

I'm assuming it's the former, but any clarification is appreciated.

Dean
USBC Silver Level Coach
BCU Graduate - Mastery of Layouts
BTM contributor
Arkansas
BCU Graduate Layouts
BCU Graduate Layouts
Posts: 477
Joined: January 24th, 2012, 11:02 pm
Positive Axis Point: 4 1/2 Left x 3/4 Up
Speed: 18.5 off Hand
Rev Rate: 350
Axis Tilt: 17
Axis Rotation: 55
Heavy Oil Ball: Guru Mighty
Medium Oil Ball: Guru
Light Oil Ball: Torrid Affair
Preferred Company: Radical

Re: Fit Question

Post by Arkansas »

The original span-to-thumb pitch chart is in Bill Taylor's book on fitting. In it he states that the span to pitch relationship is used to maintain a 63* angle, which he says is the optimal release angle. For this reason I would think that you'd need to base it off the thumb pitch you actually use. He goes on to say that if a bowler has a good fit and wants to experiment with an additional 3/8" forward in the fingers they should reduce the span 1/16". So it's based on the actual pitches used.
James Talley
User avatar
stevespo
Member
Member
Posts: 584
Joined: August 11th, 2014, 8:07 pm
THS Average: 225
Positive Axis Point: 5.75" x + 3/8"
Speed: 17+ off hand (camera)
Rev Rate: 375
Axis Tilt: 12
Axis Rotation: 45
Heavy Oil Ball: Phaze II, Altered Reality
Medium Oil Ball: IQ Tour Nano, Zen, Phase III
Light Oil Ball: Electrify Pearl

Re: Fit Question

Post by stevespo »

Arkansas wrote:The original span-to-thumb pitch chart is in Bill Taylor's book on fitting. In it he states that the span to pitch relationship is used to maintain a 63* angle, which he says is the optimal release angle...
I'm curious - could you elaborate on what the 63* angle is?
Thumb angle along the grip centerline plane?

I've been trying to locate that book for years. They show up for big $$$ from time to time.

Thanks,

Steve
16 mph (14-14.5 on monitor), 375 rpm, PAP 5 1/2 x 3/8 up, AT: 12*, AR: 45*
elgavachon
Trusted Source
Trusted Source
Posts: 3174
Joined: January 18th, 2010, 9:21 pm

Re: Fit Question

Post by elgavachon »

I heard somewhere (don't remember when or where) that the new information is using 1/4" more forward in the thumb than the old charts. Any one hear this who can clarify? New IBSIA classes maybe?
Arkansas
BCU Graduate Layouts
BCU Graduate Layouts
Posts: 477
Joined: January 24th, 2012, 11:02 pm
Positive Axis Point: 4 1/2 Left x 3/4 Up
Speed: 18.5 off Hand
Rev Rate: 350
Axis Tilt: 17
Axis Rotation: 55
Heavy Oil Ball: Guru Mighty
Medium Oil Ball: Guru
Light Oil Ball: Torrid Affair
Preferred Company: Radical

Re: Fit Question

Post by Arkansas »

See attached from the book.
You do not have the required permissions to view the files attached to this post.
James Talley
User avatar
bowl1820
Trusted Source
Trusted Source
Posts: 1470
Joined: July 9th, 2012, 10:09 pm
Location: Central Florida

Re: Fit Question

Post by bowl1820 »

Thought I'd throw this in for you:

Troubleshooting Grips Issues: The Coaches and Pro Shop Operators Guide to Grip Symptoms and Fixes

The 63° is mentioned on page 3.
Troubleshoooting-Grip.pdf
You do not have the required permissions to view the files attached to this post.
"REMEMBER, it isn't how much the ball hooks, it's where."
guruU2
Trusted Source
Trusted Source
Posts: 1057
Joined: March 31st, 2010, 7:27 pm
Location: Camp Springs MD

Re: Fit Question

Post by guruU2 »

Arkansas wrote:See attached from the book.
Arkansas wrote:Attachments
The 63o is extremely important. Bill Taylor, back in the 50's and 60's, did the "grunt" work for up by plugging and drilling over and over and over and over came to the conclusion that the hand, for most bowlers (er 90% plus) should sit in the ball at 63o. A couple of computer studies in the early 90's (sorry, I forgot them as named references) came to the conclusion the hand should sit in the ball at 61.7o thus confirming Bill's work (who did this "grunt" work with out computer help). There are exceptions to this (Del Warren, for example, is one due to his physical uniqueness to his hand). The IBPSIA chart is rock solid guideline for thumb pitches for most people most of the time.
-Gary Parsons
If one does not know one's product, one can not manage nor promote the product one does not know.
ads
Member
Member
Posts: 657
Joined: November 22nd, 2014, 6:07 am
THS Average: 205
Positive Axis Point: 5 5/8 up 3/4
Speed: 14 mph off hand
Rev Rate: 300
Axis Tilt: 15
Axis Rotation: 60
Location: Hong Kong

Re: Fit Question

Post by ads »

bowl1820 wrote:Thought I'd throw this in for you:

Troubleshooting Grips Issues: The Coaches and Pro Shop Operators Guide to Grip Symptoms and Fixes

The 63° is mentioned on page 3.
Troubleshoooting-Grip.pdf

How does it define length of span, edge to edge (with finger inserts and ST) or cut to cut (without finger insert and ST)?
Adrian
Right handed
PAP: 5 1/8 up 3/4
Speed: 15.5 mph (Kegel Specto)
Rev: 350 RPM
Axis tilt: 18-20*
Axis rotation: 60*
User avatar
bowl1820
Trusted Source
Trusted Source
Posts: 1470
Joined: July 9th, 2012, 10:09 pm
Location: Central Florida

Re: Fit Question

Post by bowl1820 »

ads wrote:

How does it define length of span, edge to edge (with finger inserts and ST) or cut to cut (without finger insert and ST)?
A persons span is measured from gripping edge to gripping edge.
"REMEMBER, it isn't how much the ball hooks, it's where."
TonyPR
Trusted Source
Trusted Source
Posts: 1386
Joined: December 14th, 2014, 3:08 am
Preferred Company: Radical
Location: San Juan, PR

Re: Fit Question

Post by TonyPR »

The Wiki fit is just a starting fitting guide, if you are curious about it follow it exactly as it recommends. In your case I would just adjust from what you have comfortably used for years depending on where it hurts(if it hurts) or what feel changes you wish to achieve. Why do you want to change your fit? Are you having any issues with pain or blisters? If so for how much time have you had them? What are your expectations from the new fit?
Silver Level Coach
Kegel KCMP1 and KCMP2 Completed /Approved Exam
Kegel KCMP3 Completed
Kegel Certified Pro Shop Operator
Free agent
User avatar
deanchamp
Trusted Source
Trusted Source
Posts: 455
Joined: August 4th, 2010, 10:23 am
THS Average: 220
Location: Melbourne, Australia

Re: Fit Question

Post by deanchamp »

Arkansas wrote:The original span-to-thumb pitch chart is in Bill Taylor's book on fitting. In it he states that the span to pitch relationship is used to maintain a 63* angle, which he says is the optimal release angle. For this reason I would think that you'd need to base it off the thumb pitch you actually use. He goes on to say that if a bowler has a good fit and wants to experiment with an additional 3/8" forward in the fingers they should reduce the span 1/16". So it's based on the actual pitches used.
Yeah that's what I was thinking, that the relationship between span and angles has to stay the same.

The 63* angle is interesting, I wonder if that would still be the case with the modern release requiring the fingers stay in the ball a bit longer once the thumb has exited, or if this angle is independent of how you release the ball.
USBC Silver Level Coach
BCU Graduate - Mastery of Layouts
BTM contributor
guruU2
Trusted Source
Trusted Source
Posts: 1057
Joined: March 31st, 2010, 7:27 pm
Location: Camp Springs MD

Re: Fit Question

Post by guruU2 »

deanchamp wrote: The 63* angle is interesting, I wonder if that would still be the case with the modern release requiring the fingers stay in the ball a bit longer once the thumb has exited, or if this angle is independent of how you release the ball.

A most interesting insight. I knew Bill for his last 10 years and my sense is that he would hold that the "angle is independent of how you release the ball". Yet, he did recognize that the 63o was not an absolute for all bowlers all the time.
-Gary Parsons
If one does not know one's product, one can not manage nor promote the product one does not know.
User avatar
deanchamp
Trusted Source
Trusted Source
Posts: 455
Joined: August 4th, 2010, 10:23 am
THS Average: 220
Location: Melbourne, Australia

Re: Fit Question

Post by deanchamp »

Thinking about this more, another quirk in the numbers seems to arise when shortnening the span to allow for more fwd in the thumb.

For e.g. If my Middle Finger span was 4 1/2" and I had a 90* thumb angle, I woud get 1/4 reverse in my thumb linear pitch. If I adjusted that to 1/4 forward, my span would be reduced to 4 3/8".

But to get a 1/4 forward on the chart with the same thumb angle, my span would have to naturally be 3 1/2".

So in this respect, I would still be quite overspanned compared to how long my fingers should be for the equivalent foward thumb angle, according to the chart.


Also found this post from Jim M:

Verbatim from the IBPSIA Fitting Manual:
"It is essential to adjust the span when changing forward or reverse pitch".

1) For the fingers, the span adjustment is 1/16” for each 3/8” pitch change.
2) For the thumb, the span adjustment is 1/16” for each 1/4” pitch change.
3) All adjustments should be made off of a good base grip.

Which is slightly different to Bill Taylor's adjustments - he goes on to say that if a bowler has a good fit and wants to experiment with an additional 3/8" forward in the fingers they should reduce the span 1/16".
USBC Silver Level Coach
BCU Graduate - Mastery of Layouts
BTM contributor
Post Reply