u/Buecherer

My daughter is 7 years old and has just grown out of her Mini sized bike.
So we got a Junior one.
I have two sets of tires 20x1-1/8 and 20x1-3/8.
Which ones are supposed to be faster on a concrete/dirt BMX race track?
Personally I would opt for the wider tires, as on road bikes the trend seems to go away fromthe super narrow ones...
Thx!