I have an 08 250 XCF which I purchased last year. I wanted an XCF-W, but none were available at the time. I find the gearing too short for some of the riding I like to do, (everything from single-track to dual sport).
I looked into putting in a 300 and 320 big bore kit, and raising the external gearing some more. I'm currently running 14/48, (13/48 is stock for an XCF).
By going to a 320 kit, the lower half of the motor will torn apart and I have the opportunity to put in different internal gears. The gear sets to convert it from an XCF to an XCF-W are expensive, (about $800 to $850) and honestly, I don't think the expense is worth it since the cost of gears, and big bore puts it close to the cost of upgrading to a 400 XCW, (albeit with a heavier feel, and approx 20 lbs).
My question to you, is there another option I should consider to get a wider gear ratio? Since I ride single track, (my club actually maintains a single-track trail in the UP of MI) just running a taller gear set (14/44) isn't going to help at low speeds.
I would be interested to learn what other inmates have done who have been in a similar circumstance as I. I love the light weight, but running at 55 mph make the motor feel like it it going to explode!
Thanks for listening!