Hey there
First, I was wondering after my today’s ride if there are any major differences between tyres. I started riding street and trial stuff this spring after 3 years of just basic stuff. I’m riding a few years old stock qu-ax crossfire 20" uni with 2 1/2" wide tire and a kh street gel seat. The question is, would a 2.5" tyre help on high jumping?
My second point is about the tuck. I’ve found a lot of help here searching but there are couple of things to which i couldn’t find answers. I do think i do at least some tucking since i land my hops with the seat next to my chest. My records are about 50cm right now. The thing i was wondering is that i don’t happen to hop much higher than the ledge i’m jumping into, no matter on what height it is but every time i feel like i’m ready for next step i land it on first try. So is it just inside my head or is there possibly any improvement in my hops and/or in tucking technique?
If it helps anyone, i’m 175cm tall, weighing about 63kg. Sorry for long post and thanks in advance! 
and yes, i also know that they are 19" so i was considering about buying a new uni at some point, perhaps in the summer… But thanks for that thread I’ll take a look!
Seems like a good compromise for now since it’s quite cheap and probably still better than my current one!