Question

why the exhaust gas is hotter than silencer

Answer 1

Silencers are the exhaust passage for your bike's engine. To reduce the effects of harmful exhaust gases, bike manufacturers provide chambers within stock silencers to curb sound and emission. The exhaust gases bounce off these chambers and thus tends to keep the silencer hot. The silencer pipe always stays hot near the engine.

If you replace the stock silencers with free flow ones, that keeps the silencer cooler as gases are thrown straight out, but will create a racket and attract cops, also they are harmful for the engine in the long run.

Answer 2

Silencers are the exhaust passage for your bike's engine. To reduce the effects of harmful exhaust gases, bike manufacturers provide chambers within stock silencers to curb sound and emission. The exhaust gases bounce off these chambers and thus tends to keep the silencer hot. The silencer pipe always stays hot near the engine.

If you replace the stock silencers with free flow ones, that keeps the silencer cooler as gases are thrown straight out, but will create a racket and attract cops, also they are harmful for the engine in the long run.

Hope this helps. 

please mark it as a brainlist answer please Dee