Well it's only because when you change down gear the RPM shoots up. But the rpm's decrease when you change up. So long as you don't apply pressure to the gear shift before you intend to shift it'll alright. It does a little bit of wear but nothing that will effect it drastically over the bikes life. You'll have to rebuild the engine before you have to do the clutch.
GP racers don't use the clutch and faults due to transmission aren't because of lack of clutch.
Yeah you can upshift without damaging the gearbox but you have to get the revs bang on or it's not going to feel good basically roll off the throttle and simulraniously shift up and blip the throttle, you will know when you get it right as it feels awesome!
Yeah you can upshift without damaging the gearbox but you have to get the revs bang on or it's not going to feel good basically roll off the throttle and simulraniously shift up and blip the throttle, you will know when you get it right as it feels awesome!
+1 I didn't want to go into too much detail (and be wrong) lol.