Is usually three or four odysseys at the flat track I've got mine tuned up in a clutch rebuilt and I'm getting a good speed but I'm having trouble in the turn keeping it level and down low My brother has skinnier rear tires and he's spinning out a lot of times especially when they pull the tires down and we can use the bottom of the track more so my question would be I was thinking of using a sway bar but I'm not sure if I should put one on the rear or front I know it'll be custom any help would be appreciated

If you do this then you will most likely have to install a rear sway bar.
The oddy has terrible under steer. They push like a pig in the corners which is why we have to drive these machines and turn them with the rear brakes. It's touchy. Too much rear brake and you spin out, to little and it pushes into the wall (or over the side of a mountain).
To get more over steer rear sway bar - to get more under steer (push) front bar.
One of the things sports car racers like me did back in the day was to remove both bars when it was raining out. It REALLY helped with track grip in the corners. I had to run several races on slicks. Never spun out once and that's unheard of with slicks in the rain.
In my opinion a sway bar actually causes the correct wheel to lose grip so that you get your desired push or over steer. Obviously ANY loss of grip on ANY wheel in the rain is a very bad thing with slicks. I can't prove that but I know what I felt racing in the rain with slicks. Just my opinion.

Side note: I see that big mirror on the right of the machine. Obviously vision is a problem with stock oddy mirrors. Back in the early 90's backup cameras started to come onto the market on high end vehicles. I thought about installing one on my formula race car so that I could see where everybody was at before we dive into a corner at 150mph. Never got around to it because they were very expensive at the time. I wanted the screen just above the steering wheel directly in my line of sight. Never got around to that project though.
Just a thought.
CO

Thank you for the response in the details information about push and understeer I am going to try a rear sway bar to help get more oversteer.
I have found that grabbing the rear brake going into the turn helps the back end slide a little bit and then I can turn right and get right back on the throttle to get through the turn.
Thanks again for your thoughts and I will be installing a sway bar hopefully before 2 weeks when we go racing again

Looks like that mirror on the right is missing and it is an illusion of the picture. Believe it is the air cleaner.

Good eye. I missed that.
The pic caused me to jump to a conclusion because that's the issue I had with my formula car.
CO

Keep in mind that a sway bar causes spring rate change.
You can't just slam on a bar or tube and call it good.
Tube thickness or bar diameter makes a difference. Some formula guys had a dozen tubes and a dozen shocks/springs.
There is math involved but I don't know what it is.
In my opinion I would go thin wall or small bar because the oddy is a light machine.
CO

You could also try this viewtopic.php?f=1&t=20571&hilit=brake+arm for some more feel and power on the rear brake to get the bum to come around. I built that for the front brake because I needed more power to lock the front wheels. It works awesome.
CO

Yes my brother's machine is missing the right mirror He's not really concerned about it I was going to buy him one but if the price is right on eBay I'll buy one or if I find one locally.
Air filter connected to PWK 39, danifold and Montessori? Reed cage
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Yes I did some reading about spring rates being affected by the sway bar I do have work shocks dual rate shocks in the rear I'm going to try as you suggested a thin wall sway bar or a smaller diameter I got to look at the arc of the outer wheel and match that to the sway bar.
Lol
I maybe just need to do that master cylinder lever modification and I'll have more breaking than that may help too I'm not sure which one to go about first rear braking pressure could be increased and that may help it spin around in the turn

Have you tried running staggered tires yet?

I have read about staggered tires and needing to know the radius and the angle of the banking and some of the math is getting crazy so I wasn't sure I should even go down that road I have a 69 10 10 which is a 22-in tire the next size down isn't like a 21 or 20 so I was concerned that it'd be too much if I staggered them I'm working on getting a sway bar now

Here's an article on a flat track Pilot. They list the tire sizes they used. Some sizes might not be made anymore.