# Weight distribution of steel rings on bimetal yoyos?

#1

For bimetal (aluminum / steel) yo-yos, I’m curious exactly what percent of the overall yo-yo weight is in the rings?

I saw someone post a pic of a de-ringed Katana and it was cool!

the steel rings on my katana came loose after a bump, so i pried them off with my fingers and took the opportunity to play with the lightest functioning yoyo i’d ever played with

it works surprisingly well and is stable, i just had to be extra gentle with my trick movements

They said the weight of the Katana rings was 31.6g versus 66.3g total, meaning the aluminum cups are 34.7g. So the steel is 48% of the weight on the yo-yo, about half?

Anyone else done this experiment or know the weight of steel rings on other bimetals?

9 Likes
#2

Also a cool related topic that didn’t get enough love, you can get the rings off… you can get the rings back on, too

4 Likes
(Joseph) #3

This is exactly why I only use bi metal Yoyos on wood floors or carpet.

1 Like
#4

Yotricks said the iYoyoSteel had a ratio of 1:7 (body:rim) in their review

3 Likes
(Mk1 Yoyos) #5

That ratio is not possible for a yoyo with a standard diameter. Each cup would have to be only 4 grams, with the rings weighing 28 grams apiece.

2 Likes
#6

Specific gravity of Aluminum is ~3.5 compared to Steel at ~7.7 so that implies it should be more like 2x?

(SF Yoyos) #7

It’s very uncommon for weight rings to be that percentage of the overall weight. They’re usually less significant.

6 Likes
#8

Topyo posted on their insta their Refraction was like 33g of the total weight (63g) or sommat

2 Likes
#9

Right, I found that reference

The outer ring has a weight of 18.5g, which is a very heavy weight, but the total weight of the ball is only 63.5g.

Let’s see

two outer rings = 18.5g × 2 = 37g

That means on the Refraction, the rings are 58% of the weight?

bearing = 2g
axle = 1g

that accounts for 39g of the 63.5g weight. By process of elimination the plastic shell plus the hub are 24.5g. I wish I could weigh the plastic shell halves, somehow… I’m also curious how much an aluminum hub weighs, exactly.

1 Like
#10

Found this very cool pic from @jeffreypang911, presumably titanium with SS rings

Let’s see…

10.92g, 19.60g … times two … 22g Ti body, 39.2g SS rings for a total weight of 61.2g not including bearing and axle, putting it at around 65g total. That means in the above picture, the rims are 64% of the weight?

Compare to:

• Refraction, poly / steel 58%
• Katana, 6061/ steel 48%
6 Likes
#11

I’d ask @Kyo. He would know.

1 Like
#12

I remember when he posted this picture. It’s the Fulvia BTM-R

1 Like
#13

overthrow has 2/3 on the rim apparently

3 Likes