Originally Posted by HellSickle
I was going to put an SX head on my '11 300 XC-W. The higher compression is supposed to boost low end torque, especially at our high altitude.
I was chatting with a guy on the trail this weekend who had done the mod. His already miserable gas mileage got worse. This might dissuade me.
Anyone else have experience on gas mileage differences? I've finally got my jetting sorted out, and I'm still disappointed with the mileage. I'm not sure the additional torque would be worth the decreased range.
I'm callin BS on the mileage claim
It doesn't require a rejet and the higher compression makes the motor a bit more efficient powerwise so unless he's twisting it more I think he's mistaken. Lots of 300 running around out there with crappy jetting.
I got the head, I saw no discernable difference in mileage but a nice improvment in power. It pulls a 1 tooth smaller back sprocket as easy as it did the stock gearing so if anything that will help mileage also. I had it in the desert this weekend and it was rippin nicely in the cold weather so if anything I'm a little rich the rest of the year. I never worry about it much though, 4 gal tank was some of the best $$ spent on the bike.