View Full Version : How fat is my FatSac?

03-03-2009, 11:49 PM
Well I am taking advantage of the cold weather and learning the in and out of the new to me ride.

I have 2 rear FatSacs, they are about 68"L x14"Wx8"H. They have a number on them of 112706101670. How much weight are they?

There are no numbers or name on the front sac. It is more of blue ballon in a gray bag. I has the ends ln it like a water bed.


03-04-2009, 12:11 AM
400lbs. Those are the factory Grav 3 locker sacks in the newer LSV's

03-04-2009, 12:19 AM
Sorry I just realized I started thread in the wrong section...

Is that 400 each?

03-04-2009, 09:32 AM
yep.. 400 each
The last few digits on that number denote the size.

03-04-2009, 10:48 AM
04 has it, but as an engineer, i gotta expand! :)

multiply 10x16x70 =11200 in^3.
11200/1728 = 6.5 cubic feet
6.5ft^3 * 62.4 lb/ft^3 = 404 lbs

03-04-2009, 10:56 AM
What? Not down to the ounce?

03-04-2009, 11:05 AM
guess now I have to go to the gym since my gravIII system is actually 1212, not 1200lbs and I can lose that last 12lbs.. :(

03-04-2009, 11:49 AM
well, what ever it takes, i weigh myself the other day, was right on the line for "clydesdale" category in a race. i won the category! but on the other hand, i would have taken 3rd in my correct AG.

so kane, ounces are not important, its how you win the race :o

sandm, you gotta realize that there is always a bit of air in the bag, so you still only have 1200

03-04-2009, 01:34 PM
Thanks guys,

any idea to get the weight the front one besides fill it up at the weight station.

yearround, if i took a picture of it can you do the math :) j/k

03-04-2009, 02:02 PM
sure, just make sure the picture is close up of the stamped model serial number. the last six numbers are the dimensions of the bag. then i can do the math, or walk you through it:)

03-04-2009, 03:03 PM
I am in sales. That means we use generalizations and don't worry about the details. We only know enought to sell it and turn the order and wait for someone else to take care of the details! HA

03-04-2009, 05:05 PM
sandm, you gotta realize that there is always a bit of air in the bag, so you still only have 1200

nice. now I can sleep in again :)

03-04-2009, 09:13 PM

Pictures would not do any good on the front sac. As it has nothing, any where on it. I do have me measurements if you care to get your slide rule out. This one is like a barrel, I measured the seams, it 32" long and has a diameter of 16". It has 2 waterbed type hook ups on end and a vent at the at the other end. It was stuffed in a grey sack with a smaller zipper on it. It too had nothing on it.


03-05-2009, 10:59 AM
volume of a cylinder is pi*D^2*H/4
3.14*16^2*32/4 = 6430 in^3
6430/1728 = 3.7 ft^3
3.7*62.4 #/ft^3 = 230 pounds
dropped a few decimals for the sales guys, want to ensure that some people still sleep well.

03-05-2009, 11:06 AM
No opinion on this from the Z's? I'm surprised they could resist.

03-05-2009, 11:20 AM
Thanks yearround! I am glad I took head medicine b4 I read ur reply. I will make note as to their sizes.

As my family are beginners in the surf arena. Is this enough weight to give it a try based on my boat (2002 OB LSV) and 400 on driver side (I would guess to get extra driver weight) and the 230 in the front? It would appear that I may be to stuff the other 400 in the front...as stated we are newbies..

No opinion on this from the Z's? I'm surprised they could resist.

I am confused..:confused:

03-05-2009, 12:59 PM
I believe zegm and Mrs. Z are both engineers.

Check the wakesurfing forum for info on ballast. I'm sure somebody has your boat.

03-05-2009, 01:34 PM
Mcdye, What you want with that hull is to get your surf side rub rail in the rear corner about 3 inchs from the water-boat will be leaning over that way. Start with 500-700lb in the rear locker and fill the front bag in the ski locker full and if you have the wakeplate put it about 3/4 up and about 9-10mph should get you started surfing. One other thing water depth can and will affect your wave-any shallower than 10 feet and you wont get a wave. Do a search for "looks like im not sitting level" and it should pull some photos of my old boat-03 lsv sittin with the surf ballast full to give you a idea.