72 spur and 30-33 pinion is a good range for me. 30 is the smalles that will fit with a 72 spur with the CE.... also, depends how old your nephew is. If my kid was driving my X-ray I would probably get the 75t spur as it allows pinions smaller than 30. I gear my kids motor low as he does t need to go fast right now and unattended he will practice with the buggy for over 15 minutes. I can be comfortable knowing he's not blowing up his motor geared low and the 72 spur may not allow you to gear low enough. That said I've also run some of my fastest laps at 75/29 on a tight high grip, technical track... my 2 cents...
Originally Posted by
billsharp34
I got my nephew a xb2 for xmass. He is new to racing. What is a good pinion and spur for a 17.5 motor on small indoor track.