Power up

When I ride the bike in this morning, power of it was suddenly declined. On the flat road, the maximum speed was only 40km/h. On up slope, it was only 15km/h.
So, I once abandoned to go to forest road today. But I bring it to bike shop and it was fixed. The reason of power decline was blocking of muffler. Mass of carbon blocked the narrow pass.
After deleting the mass of carbon, my bike ran smoothly and powerfully. I recorded the fastest speed of the bike 90km/h. So, I could pleasure riding in forest road today.