For sale is a used hmf fuel optimizer programmer for the yfz 450r in great shape I only had it on my atv for about 5 hours. Works great I put a tune in it from atv magazine that really woke up my yfz made big low and mid range power. I'm just selling because I don't ride my yfz much and am putting it back to stock to trade in for a side X side sold as is thanks.