back end shaking at high speed

[Kirt13]

Like the subject says, I just built this quad. Everything is new except for the hubs. They are used but I was told and it looks like they are straight. Is it possible that my tires are bad? They are Kenda Klaw 20x11x9. I'm not sure of my top speed yet. My friends 450r was clocked at about 80. I walk past him. Seems like the shaking starts at about 70-80.

[pimpt250r]

hey Kirt13,,when that happened to me on my R my tires were at different PSI ,20x11x9 holeshot XC's,but before i did that i replaced the carrier with a lonestar ,made sure the tires were the right psi , and now my front shakes a little at high speed ,, but I know i need new front a-arm bushings ,
gonna get a set from x_system on here hopefully they work as well as his seat bushing kit
let me know what you figure out

[Kirt13]

Thanks bro. You know that might just be it. I filled them just by feeling.

[pimpt250r]

thats what i do i just give a push with the foot

it all made sense when i put the air gauge on there and it was like 10lbs difference from 1 side to the other