This is a 1515/1y no fins, jato-58/22-rc-monster, Thats probobly the smallest spur and pinion combo you could fit with finned as I have a tad more room for smooth can, as wade said you can grind down the 2 fins that hit. Id go with bigger pinions 24-26 and adjust spurs around that.
Jato spurs
3905 spurs
