Reb - put calipers on those pipes and make sure (at the very least) that they are 1-3/8 inch outside diameter. If the pipes are too small in diameter, they may not flow as much a high rpm. At low to mid rpm they would be fine. At high rpm is where the problem would crop up if they're too small. The inside diameter is where it is important, but start on the outside to get an idea.
2016 Honda Rebel 250 - The "Piglet."
AFR sensor equipped and downsized to a 0.105" main jet.
The only changes so far.
Bought on 6/29/19 with 44 miles.