GC2 Measure Swingspeed w/o hmt?

[kianphin]

Hi, I have GC2 and I read from the web someone saw a GC2 in golf shop can measure swing speed without hmt unit. Is it possible?

[bubba22]

No. It estimates swing speed fom ball speed based on estimated smash factor.

[kianphin]

No. It estimates swing speed fom ball speed based on estimated smash factor.

Hi bubba, how to calculate swing speed with ball speed and smash factor?

[bubba22]

Simply assume the smash factor is fixed. Let's say 1.5. From tat you can estimate th swing speed. Smash factor is ball speed/swing speed. Obviously one s estimating th smash factor so it's not accurate.

[john8888]

from trackman

Club head speed actually varies significantly depending on where on the club face you are looking. On average there is a 14% difference between heel and toe speed.

This means that if you have 100 mph club head speed in the center of the club face, the speed of the heel will be around 93 mph and the toe 107 mph.

This is primarily due to two things: 1) the further distance from grip to the toe of the club compared to the grip to heel 2) the rotation of the club head during the downswing. Likewise, the club head speed low on the club face is higher than high on the club face.

[john8888]

from
http://www.tutelman.com/golf/ballflight/smashfactor.php

Loft to Best Smash Factor
0 = 1.488
5=1.482
10=1.465
15=1.437
20=1.398
25=1.348
30=1.288

[bubba22]

What is your point John? I understand how smash varies with loft and club speed varies deepening wher you measure it. The point is that the GC2 without HMT estimates the club head speed. Without HMT the GC2 doesn't directly measure clubhead speed.

[john8888]

how to calculate swing speed using GC2 ball speed using smash factor and loft

[Dax]

Does this not assume that you are hitting the ball from the perfect spot on the clubs face? Also what do they mean by loft and where will you get this measurement? I'm sure there are other variables as well.

[goatbarn]

Smash factor is dependent on swing speed, so surely you know you can't use smash factor to calculate swing speed.

Bottom line is no it cannot be used to show you swing speed. It can certainly guess. It uses a smash of 1.45 for drivers.

So if you hit the ball in the center of the face, and the driver face is not dead, it MAY be close.

That's all the stock I'd put in it though.

[bubba22]

how to calculate swing speed using GC2 ball speed using smash factor and loft

How would the GC2 know the loft?

[Dax]

I'm sure if there was an easy way to calculate smash factor they would have figured it out by now? But I just can't see how it is possible to calculate smash factor from ball data.

[bubba22]

It will be all an estimation. Not saying its bad but it won't be perfect. You can improve it by changing the smash factor based on ball speed, launch angle and spin. For example if the ball speed is say 140 mph with launch around 12 and spin 2-3000 then most likely that's a driver so smash will be say 1.4. If tha ball speed is 80 with 30 degree launch and a high spin then that may be a wedge so use a smash of 1.2. The estimated club speed with that will be fairly close.