My 500 ho has button on either side of dash, can't find buttons to change the clock on my brother's 500 classic.  Thanks

Under the seat along the frame rail near the battery you will see a small button,

Will have to look for this, I've been trying to understand how to do anything with the display, I just assumed there was nothing to change it with.

i actually had it once change to a trip odometer and I have no idea how or that it even had one.  It changed back at some point so I've always assumed there
must be some way to change it.

Tried to locate the damn button, like you said, under the seat and near the frame rail, but... Could not find it. It is not in any of the documents I received when I bought the ATV.

In the manual, there is a nice image of the dashboard but no instruction referring to the clock adjustment.

I will have to ask the seller next time I go for a check.

As for the rest, I like the machine fair enough.

I just picked up mine and set the clock. Took me a bit to figure it out.  Hold down the button on the right to change minutes.  Just push one at a time for hours.