The TL01 is the same as the mini and has set holes for three different types of pinions. So on the three sets of holes it should tell you the size pinon you can use. Changing the spur gear invloves changing the main drive gear so it would have to be a tamiya or maybe three racing part to allow you to do this.
I believe there was a sport tuned gear set for it that allowed you make the gearing higher using the same holes but bigger pinons. Although that might have only been the TT01.
It's a long time since I raced TL01's in the tamiya eurocup and my memory is getting worse as I get older
so I can't be sure of if there is a speed tunes gear set or not.
Actually I have just found on on e-bay. So yes they did do a speed tuned gear set.
http://cgi.ebay.co.uk/Tamiya-53342-T...63b113ffd712ca