WR-250R 270mm Oversize Front Brake Rotor Kit

This is a QTM kit which has a Brembo 270mm rotor vs. the stock 245mm one.
This kit is sold through Yamaha motorcycle dealers as it comes from their 2010 accessory catalogue (which has lots of neat stuff to get rid of your spare change on). :)
The Yamaha part number (here in the USA, anyway) is:
GYT-0SS56-32-03
It lists for $299 US dollars.

I'll be putting this on this weekend, and I'll report back on the results. :)

Will you be going back to the stock disc and carrier??

We'll see, but I get the feeling that's unlikely. :)

Alrighty, then.
270mm rotor installed (along with a new set of EBC sintered pads) and a 120-mile sporty street test ride completed.

First, a couple of notes on removing and installing the rotors:

1) You'll need a T30 torx bit to remove the stock rotor mounting bolts (there's 6 of them).
Also, I heated the bolt heads up with a propane torch to help loosen the thread locking compound of these bolts.
They don't need to be glowing cherry red - just hot.
Once the stock rotor was off, I also removed and threw away the stock rubber damper that resides just behind those mounting bolts.

2) The stock rotor mounting bolts are of a typical flat headed design.
The new Brembo/QTM rotor in machined to be used with countersunk bolt heads.
Yes, just like when removing the stock rear sprocket and installing one made for a YZ, you'll need some countersunk mounting bolts.
Luckilly, my local Yamaha dealer (where I work :) ) had 6 nice, new ones in stock (because I put them there :) ).

The rest of the operation is straight-forward.
Bleed the front brake system when done.

How's it work?
Very well, and as well as you'd expect.
The stock front brake setup is good, but nowhere near as much front brake as I like to have at my fingers.
With the new 270mm setup, braking power feels about 10% - 15% stronger.
Not a night-and-day change like a motard race setup of a 320mm rotor and a Brembo radial-mount 4-piston caliper and radial master cylinder will give you, but a very noticable improvement.
I call it night-and-dawn. :)

I can now howl the front tire with a moderate 2-fingered pull on the lever, and braking with just my middle finger (how I always do it) is improved a fair bit.
If I were to try to do a 1-to-100 rating of the before-and-after brake performance, I'd call the stock 245mm setup a 60 and the 270mm setup a 70.
Not bad for just bolting on a couple of parts that list for $299.
That motard race setup mentioned above would cost you about $1,200, by comparison.

In a nutshell, it's worth the money if you miss stronger brakes up front like I did.
This is an easy and very basic way to get stronger front brakes.
The next logical addition is for me to install a braided steel front brake line.
Probably next payday. :)

Interesting
You might want to look close into master cylinder piston diameters
You may be able to have your master bored , there are different bores using the same basic master
That one will take some sleuthing

I agree on the braided line, that always makes a noticeable difference

Yeah, it ain't bad the way it sits, but I know it'll see more money before long. :)

so what did you do with the old hanger ? i did a swap to a rm wheel and a kx caliper/hanger for my x. wanted an extra 21.
will that nissan piston swap from r to x hanger ?

the wr250x master cylinder has a larger bore, you can buy it new for fairly cheap if a stainless line still isn't quite enough.

dtx wrote:

so what did you do with the old hanger ? i did a swap to a rm wheel and a kx caliper/hanger for my x. wanted an extra 21.
will that nissan piston swap from r to x hanger ?

The original caliper bracket?
It's sitting on a shelf doing nothing and wondering what to do.
Why?
You wannit? :)

ware in ct. on line in mass,like to eyeball it

I'm down in Hanover.
I'll send it to you and if you want it, just flip me a few bucks to cover the handling.
Send me a PM with your address and how you want it sent (mail or UPS). :)

Stock front brake for me was way too weak for the road. Dirt was fine. I'm used to sport bike brakes and the BEST front brake of any bike I have ever ridden: Husky SM610.

Anyway did the following: Galfer SS line, QTM 270mm rotor kit using supplied pads and 250X master cylinder. Now I feel "safe" on the road and still easy to modulate and not too much power off road.