If the bike dont have enough power for the gearing or weight a engine wont fully rev out. I remember 5th gear top speed rpm was a thousand or 2 lower than 1st gear top rpm due to not having enough power. See how high it revs in nutrual. Thats how high it should be able to hit in at least 1st/2nd gear.
If you geared it taller for higher top speed that will cause your rpms to not go as high as they could because lack of power to pull that gearing. Stock gearing the bike cant even fully pull 5th gear out. And the rev limiter says to 12,000rpm thats just for show that engine is not capable of reving that high its top rpm is only around 7000-8000 I cant remember because after all they use a cloned honda xr200 dirt bike engine.
