I have three objections to this lujvo (in increasing order of
seriousness):
1. The order of bajra plipe renro in the veljvo doesn't
matter; you chose the order that's conventionally used in English, but of
the six possible permutations, the optimal (lowest scoring in the
lujvo-tastiness scoring algorithm) permutation in Lojban is bajra
renro plipe. So all other things being equal, this lujvo should be
called bajrerpi'ejvi.
2. Let's talk about jvajvo-ness (I'm big, perhaps overly so, on lujvo
having elegant place-structure derivations). Currently bajra, plipe and
renro modify j₁ or j₃; in either case there is no justification
(that's not specific to bajypipre'ojvi) for dropping the rest of their
places. I think it would be a little better to use (za'e) taljvi
(j₁=t₁ competes against j₂=t₂ in contest j₃ for gain j₄,
each challenging the other in property t₃) instead of jivna, for then
bajra/plipe/renro go in the t₃ spot, being the properties demanded of
the competitors (in truth, the property demanded of the competitors is to
be the best at bajra/plipe/renro). But still, if bajra/plipe/renro are
going into an abstraction place, the rest of their places should follow!
This apparent difficulty lends credence to the following point, I think...
3. What's the point of this word? Granted, I didn't know what "track and
field" meant before coming across this lujvo (I'd heard it before but
thought it just meant a running race), so if I'm getting it wrong, dismiss
this point and see it as an opportunity to clarify the meaning of this
lujvo. If I understand the Wikipedia article, it's an contest that's
centered on running or jumping or throwing. But not necessarily all three.
So why not just call it what it is, either a running contest or a jumping
contest or a throwing contest? Calling all three
"running-or-jumping-or-throwing contest" is like calling apples and
tomatoes "apple-or-tomato".