Problems getting Unilli's to stay sized right

W5R

New member
How in the heck do any of you guys get Unilli tires to hold their size? Seems impossible to even get 5 laps in on a set without the right sides trying to shrink back down to 33 1/4 or 33 1/2 and left rear growing to 33", cant get them to hold their size for nothing! And i do know how to size tires properly, i have never once had problems with my burris tires shrinking or growing during a race like this. Kart will start off perfect like i want, then get worse and worse as the race goes on, due to stagger decreasing. I like these tires, they seem like good tires for the money if i can just get them to hold their size for more than 2 laps! Thinking about making the right sides 1" bigger than what i want them to be, so that when they shrink in a couple laps, theyll be right where i need them lol
 

XXX#40

2A supporter
How in the heck do any of you guys get Unilli tires to hold their size? Seems impossible to even get 5 laps in on a set without the right sides trying to shrink back down to 33 1/4 or 33 1/2 and left rear growing to 33", cant get them to hold their size for nothing! And i do know how to size tires properly, i have never once had problems with my burris tires shrinking or growing during a race like this. Kart will start off perfect like i want, then get worse and worse as the race goes on, due to stagger decreasing. I like these tires, they seem like good tires for the money if i can just get them to hold their size for more than 2 laps! Thinking about making the right sides 1" bigger than what i want them to be, so that when they shrink in a couple laps, theyll be right where i need them lol
Are you heating them to 225 deg.+ and shocking them or just adding air and stretching?
 

speedy79

New member
Heating and shocking has not worked for me on unilli. What has worked for me is to air the tires up 1/2" bigger then you want them and let them sit at least a week, 2 is better. They should be at size when you let air out. Run them in hot laps and come in clean tires and put rights to 20 and drop air in lefts and let them cool. You should be good then. Store during the week with rights @ 20 psi. and lefts very low to no air.
 

bigcat6

New member
Heating and shocking has not worked for me on unilli. What has worked for me is to air the tires up 1/2" bigger then you want them and let them sit at least a week, 2 is better. They should be at size when you let air out. Run them in hot laps and come in clean tires and put rights to 20 and drop air in lefts and let them cool. You should be good then. Store during the week with rights @ 20 psi. and lefts very low to no air.
sounds very natural thing to do...doesn't distort the rubber as much this way...
 
Heating and shocking has not worked for me on unilli. What has worked for me is to air the tires up 1/2" bigger then you want them and let them sit at least a week, 2 is better. They should be at size when you let air out. Run them in hot laps and come in clean tires and put rights to 20 and drop air in lefts and let them cool. You should be good then. Store during the week with rights @ 20 psi. and lefts very low to no air.

This is spot on... Other than doing this you will be chasing your tail around in circles. These tires don't really have any memory to them so they will continue to move around on you.
 

W5R

New member
Guys i have tried using heat and shocking them in ice water like we do with burris, and iv tried using air and making them 1/2" to 3/4" bigger than i needed for the right sides and let them sit for a week, and when i let the air out and put the psi that i race with in to check them, they are perfect, but once they get a heat cycle in them, the rights shrink back down at least 1/4" sometimes 1/2" or more every single time, and the left rear will grow at least 1/4" everytime its ran! I like these tires, they do great for the first few laps, but as the run goes on the kart gets unpredictable because of the stagger changing and its driving me insane. I have a $2000 guaranteed race coming up next month and basically i have about 3 weeks to get these tires figured out, i dont want to screw it up again with stagger issues during a race. Im seriously thinking about making the rights 1" to 1 1/4" bigger than what i need and praying they come down to the size i need them to be at lol, that seems like my only viable choice right now. I have a couple more chances to run them after trying some new things, im gonna run them this weekend and see if it works, i sure hope so, if not, these tires may as well be thrown away, and id hate to have to do that.
 

PiMotive

Member
That is what I was going to suggest, too. I just put my rights on some old 8.5". They don't need as much pressure to stretch 1/2" over. Seems like they are going to hold the size easier.
 

Benji22

Member
They will not be fast if you put them on narrow rims. They don't retain a memory. Easiest way is to leave your right sides blown up and leave your left sides flat. Leave this way when your not working on them. We left ours this way all the way up until we were being called to the grid.
 
Top