flymolo
Contributor
I have a Genesis 3.1 trimmed for fresh water. I think it was mentioned somewhere else but I can't seem to find the thread- does anyone know approximately how much weight I should add (front and back) for salt water?
Genesis 3.1 weighting fresh to salt
- Thread starter flymolo
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Weigh it. Factory specs say 34#, but if you have a way to weigh yours, that would be better.
Salt water is roughly 2.5% more dense than fresh water.
So, take the total scooter weight and add 2.5% of that.
E.g. if the scooter (weighted for fresh water) is exactly 34#, then you would add .85 # (= 13.6 ounces).
Additional notes: Fresh water is not "pure water". The exact density of fresh water in any given location may not be exactly the same as it is elsewhere.
Ditto for salt water. Salinity is known to vary a fair bit around the world.
So, the whole "2.5%" thing is a ball park based on assumptions of the fresh water density that you are weighted for and the salt water density you are going to.
Fortunately, it is very likely to be somewhere between 2 and 3%. So, the most you are likely to be off is 0.5% of (about) 34#, which is less than 3 ounces.
TL;DR: Add 13.6 ounces and you'll be pretty close.
Salt water is roughly 2.5% more dense than fresh water.
So, take the total scooter weight and add 2.5% of that.
E.g. if the scooter (weighted for fresh water) is exactly 34#, then you would add .85 # (= 13.6 ounces).
Additional notes: Fresh water is not "pure water". The exact density of fresh water in any given location may not be exactly the same as it is elsewhere.
Ditto for salt water. Salinity is known to vary a fair bit around the world.
So, the whole "2.5%" thing is a ball park based on assumptions of the fresh water density that you are weighted for and the salt water density you are going to.
Fortunately, it is very likely to be somewhere between 2 and 3%. So, the most you are likely to be off is 0.5% of (about) 34#, which is less than 3 ounces.
TL;DR: Add 13.6 ounces and you'll be pretty close.
Might be easiest to just make a couple of loops of bungee and add a 1# hard weight to the outside for diving in salt water. That would also make it really easy to slide it forward/aft to get the trim just perfect.
Or don't mess with the weight at all and dive with it 14 ounces positive.
I just converted my Genesis 2.2 to a 2.1. I am definitely going to dive it in the ocean with no additional weight first, before I bother trying to make it "perfect" in salt water. Being 14 ounces positive might turn out to be good enough that I don't care about adding any weight. Also, that is what Jon Nellis recommended to me and said that he does.
Or don't mess with the weight at all and dive with it 14 ounces positive.
I just converted my Genesis 2.2 to a 2.1. I am definitely going to dive it in the ocean with no additional weight first, before I bother trying to make it "perfect" in salt water. Being 14 ounces positive might turn out to be good enough that I don't care about adding any weight. Also, that is what Jon Nellis recommended to me and said that he does.
I've been pondering this.
I have a V-weight pouch (similar to this: V Trim Weight Pouch)
I think if/when I want to weight/trim mine for salt water, I'm going to use a piece of bungee to make the V-weight pouch into a circle that will fit and hold tightly around the body of my scooter, then add lead shot to the pouch to get the weight exactly right. It can just be around my scooter body when I'm diving in salt water. Pull it off when diving in fresh.
Easily adjust the weight in it as necessary.
Never have to open the scooter up for any reason.
Easily adjust salt water trim by just sliding it fore/aft.
Tuck a lift bag under the bungee to hold it and carry it around when needed.
I have a V-weight pouch (similar to this: V Trim Weight Pouch)
I think if/when I want to weight/trim mine for salt water, I'm going to use a piece of bungee to make the V-weight pouch into a circle that will fit and hold tightly around the body of my scooter, then add lead shot to the pouch to get the weight exactly right. It can just be around my scooter body when I'm diving in salt water. Pull it off when diving in fresh.
Easily adjust the weight in it as necessary.
Never have to open the scooter up for any reason.
Easily adjust salt water trim by just sliding it fore/aft.
Tuck a lift bag under the bungee to hold it and carry it around when needed.
OP
flymolo
Contributor
I decided I am just gonna dive the scooter weighted for fresh water and see whether I can deal with it being a bit light for salt. I think eventually when I’m back to diving salt more frequently than fresh I’ll have it go the other way.
This is what I do. I don't mind it being slightly more buoyant and if it ever gets away from me in the ocean I will be happy it's at least riding on the surface someplace I could in theory find it. The people who agonize of scootering weighing in the ocean definitely don't dive in Hood Canal or Puget Sound in the winter where we have a variable freshwater lens on top of saltier water below lol.
It's not that big a deal.
OP
flymolo
Contributor
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