IMPROVING WR250R FRONT BRAKES

Have changed brake lines to SS and different pads but still want more braking power on my R. Want to go with a bigger rotor and a more powerful master cylinder. Would appreciate any recommendations for oversize rotor kits you have installed. The QTM 270mm one in the Yamaha catalog is listed for a WR250F, not R. Will it work on a R? Way to adapt the X rotor? What "bolt on" master cylinders have worked?

Thank you.

The 270mm rotor kit in the Yamaha accessory catalogue fits just fine and dandy as long as you use countersunk rotor mounting bolts.

Kit part number:

GYT-0SS56-32-03

Rotor mounting bolt part number:

90151-06051-00 (need 6 of them).

To be quite honest, as in my post I wrote in March of 2010 when I installed this kit on my then-owned 2008 WR-250R, I really wanted even more front brake than this kit delivered.
It's worth the money for the kit since it did improve the front brake performance noticably, but I was really missing the bona-fide motard racing brake setup I had on the 2009 DR-Z400SM I rode during that same time period, but that setup cost 4 times as much.
This is comparing apples to oranges as far as front brakes go, but, I'm going to tell you exactly how it went down for me, as well. ;)

If you are looking for a reasonable improvement, go for it.
I wouldn't be surprised if a different master cylinder made it even better. :)

Squeeze harder?

I find that the stock X setup brakes more than hard enough for me. Easiest way to swap would be to have a 21" rim laced to the stock X hub and rotor, then adding the stock X caliper (maybe master cylinder and brake line too, unsure if they are the same or not). Warp 9 can build you such a wheel as can Wheeling Cycle Supply. I have had no real issues off-road with the 17" front wheel and big rotor so long as I'm smart and careful when threading through big rocks, but street tires limit me to moderate to easy trails and fire roads at this point so your results may vary.

So It's about time to add some more stuff to my WRR...

I've considered the GYTR 270 kit and I think it would be worth it, but I've noticed the 320mm EBC kit as well.

I've read YZetc's post but outside of the 10% difference noted - I'm curious how much different the 320 and the 270 might FEEL. I agree with Skierd that stock is usually enough, but there have been times I wanted (needed? ) just a wee bit more.

I spend plenty of time on the street, but go offroad as well and am thinking the the 320 would be too much (if not a problem) off-road.

Any opinions?