Is it hard on the clutch and transmission to engine brake on a bike? Should you always rev match?
It is fine as long as it isn't a 2 stroke with premix gas on a long downhill.
You should always rev match. This makes your ride smoother and reduces wear somewhat on the clutch. Engine braking is there for when you aren't in a hurry to stop or you just need to slow some. The brakes are there for when you need to stop faster.
The bottom line is YES it is harder on the entire drive train - think about it - the clutch isn't impacted as much but the trans, sprockets chain, etc are all incorporated into the stopping procedure - where as if you are just using brakes you are only wearing brake pads and rotors a little (both low price and low cost installations). All that said - does it hurt the bike to downshift in a practical manner - no or only a negligible amount - they are designed to handle it - but the answer to your question is it bad/hard on the bike is still yes more so than only braking.
Compression braking is just another tool in any good rider's toolbox. Properly done, it does not cause excess wear. My clutch gets adjusted according to the maintenance schedule. Since I do this myself, I know exactly where it's set. I also know that the setting has not changed in 50,000 miles - indicating little to no wear. Stress on components from braking should be no more than stress from acceleration.
so long as you don't over do it (eg change into 1st at 60mph or something) it's okay. Let go of the throttle and change down gradually.
