I'm having Honda CBR 150R, which is two years old now. I'm facing an issue of gear shifting since the day I bought this bike. 

I've mentioned this issue to various mechanics and service centers, but they are unable to fix this. Following is the description:

1. I start my bike, and once in motion, I start shifting the **GEAR UP**. **Gear shifting works fine** in this case.
2. Now once I'm in higher gear (3, 4 or 5) and I try to shift the **Gear DOWN** with clutch fully engaged, I'm unable to shift down. In this case, I have to release the clutch just a little bit and then only the gear respondes to down shift.