How to reinforce your cage on the cheap

Posts: 411

Ok at first your going to say what the!?! why would you!?!? extra weight!!! But hear me out and let me explain the thought process....

Ok if you dont roll your cart or ride it hard enough to roll it this post isnt going to be for you...

If you roll it the cage crushes sometimes a little sometimes ALOT!
Welds at the front pull up because when the cage compresses it peals up on the weld on the front of the bar.

Hollow tubing is not meant to take BIG force. (think pop can) lol
Now if you make that hollow tubing NOT hollow think of that pop can as a solid piece of aluminum and try stomping that flat....not so easy.

So i thought hrm my experiance with racing is...guys with all out dragsters with 2000 horsepower how the heck do the hollow engine blocks handle that horse power?
The answer is this they dont have water passages....they arnt liquid cooled....they solidify the block so it has NO weakness...

They fill the water passages with concrete! What the?! Yes they do...doesnt it gain weight? Yes it does.. Does the horsepower limit far exceed the weight gained? Absolutely!

So i took off my bent old crushed bar and weighed it...then i plugged all the holes and filled it with water and weighed it.
Now if concrete is 2.5x heavier then water i will gain 12.5 pounds per MAIN bar to strengthen it HUGELY. So my cart will gain 25 pounds. Will i ever bend another rollcage bar? Not likely. Not with 6000psi strength concrete reinforced with chromoly. Will i ever pull another weld away from the frame because my bar flattened? Not a chance in my opinion.

Will it work and be WELL worth the 8 dollar bag of concrete investment? absolutely.

My only question is will it tip more being more top heavy....?
Most of the main bar is at or below the occupants hight.

Will i lose a little bit of performance being 25 pounds heavier?
A little bit but can i aford it? Yes lol with my new part lol YES yes yes.
Any cf moto owner will love the part especially if he does short trail systems or climbing wow.

Posts: 1832

Darren, you may want to look at filling your tubes with hydraulic cement instead. There is no little stones in it and it sets up hard as a rock. You can mix it as thin as you need it to pour down the hollow of the tubes and not have to worry about having any air pockets. Just a thought!

Posts: 411

How much does that stuff cost? Can I get it at home depot?

Posts: 1163

You could make a new cage of stronger steel, but it will be more expensive. You could reinforce what you have. Your cross braces are probably bolted to the main bars. Bolts bend and flex. Tighten the bolts then weld the cross bars to the main ones. You can also weld an x brace behind the seats from the main kart frame to the rollbars. Very strong, save 20lbs. If you don't have a way to keep the concrete filled bars from moving side to side you might just twist the frame rails where the crash bars are welded. (if you fill the bars with cement the main frame is now the weakest point)

Posts: 1832

Posts: 411

The main frame has reinforcements all over the place. Problem is the cage has such a large span between mounts and reinforcements. I honestly think the cage being bullet proof and not flexing will keep everything below it straight. When your on your roof all the weight is on the cage and very little is on the main frame.

Posts: 411

Ok im no builder or brick layer so i did some more research.

Concrete appears to be stronger as it has the sand and rock pieces in it but cement would be easier to use in this application glad you mentioned it.

Most cement is hydraulic so i guess i just need a simple bag of cement.
I always just referred to cement and concrete as the same thing.... i guess i know better now;-)

Posts: 301

I wouldn't do that. Concrete is just going to make it heavier and not offer much strength. Concrete isn't designed for such applications. You're likely to find that the first time you roll it the concrete has crumbled in the frame. In seismic zones, they add tons of rebar to concrete just to keep it from crumbling during small earthquakes......now imagine that concrete in something like a buggy.... I would follow the advise of reinforcing the frame with more bars before I would ever consider using concrete.

Posts: 411

The concrete is encased in rebar basically. And they don't add rebar every inch...I know reinforcing the frame is good advice I just don't like the idea of having the cart looking home made because of all the reinforcement needed for such a large span. And will likely restrict entry and exit.

Posts: 1832