The Terminator FAQ(though I would go shorter with the T-800s generally, I feel HT tends to make them too tall)
6'2"=188 cmAccording to the 1984's Making of The Terminator, the Terminator weights 200 pounds and is 6'2. He has over a thousand moving parts.
188/6=31.3 cm
toy boots should give 0.5 cm max
so a terminator should be less than 32 cm high. as far as i remember, even the shortest MMS136 (stock variant) was higher. so you feel correct
on the other hand, 1/6 Tamiya bikes are too big for 1/6 Hot Toys terminators, so i don't know what to think about all that.