250-500cc Brown coolant from my '11 WR 300

I just drained my coolant for the first time since buying this bike new in December 2011 and nearly every drop was brown. The viscosity and scent was the same as new coolant. Rust? Obviously. Where? I did not detect any oil in my collection pan; i.e. no sheen or "milkyness". First I can't get it out of 1st gear (see other thread I started on Sunday on that issue), now this. I only have about 24 hrs on it so far.

So how do you fellas diagnosis this further and remedy it? Thanks.

There shouldn't be anything to rust in the system. I have seen the discolored coolant before. I would just replace it and check it again later.

I had the same thing with my '10 WR300 after running demineralised water only(no coolant) for a road race.
When I pulled the water pump cover off to have a look, the shaft that drives the impeller had surface corrosion evident and some staining of the impeller had resulted.
I just put some good quality coolant in with the water and kept riding.
I've had no further evidence of brown in the cooling system since then, so I'd suggest giving yours a flush and see how you go.

Same thing on my 2011.

I run engine ice. I just had to drain it because of a leaky radiator and it still looked brand new after at least 50 hrs. Maybe give it a try.......

Did you buy it local. Some dealers are helpful