Timur was Turkic for God's sake.
You are right in saying that Timur was Turkic. However, since most of these people cannot tell a difference between TURKIC and TURKISH, let me give a definition of TURKIC:
TURKIC : a family of closely related languages of southwest, central, and northern Asia and eastern Europe, including Turkish, Azerbaijani, Turkmen, Uzbek, Kirghiz, Kazakh and Yakut.
Turkish people are also Turkic and they originate from Central Asia, also.
Now lets talk about the connection of Mongols and Turkic tribes. Historically many tribes are described as Turko-Mongols because many Mongol tribes became Turkofied as the moved West, conquering lands of Central Asia. This use to occur quite frequently as armies conquered new territories and settled in their conquered lands and married local girls their future generations were mixed heritage. Timur who was Turkic had such mixed ancestary as well.
Let me further clarify why the Indian Mughals who were descendents of Turkic tribes ( Babar was a descendent of Timur ) had Persian mothers and this mixed ancestary softened their features. In other words, Mughals were Persianized Turks and spoke Persian as their first language ( Babar spoke persian ). The reason for this change was that persians conquered Central Asian cities like Samarkand and Bukhara in the middle ages and the whole area was Persianized.
I know this is too much of a history lesson for most South Asians , especially form India where their successive Hindu Fundamentalist political parties like BJP have totally erased Mughal History from their curriculum during their reign. I just hope that this sets up the perspective so that they can debate intelligently.