Front brake issues
The brakes on the RX3 get some complaints, but they aren't bad. They just take too long to bed in. On most new bikes, bed-in only takes 100-200 miles of normal riding. These brakes take much longer.
Also, some bikes were delivered with rotor issues. None were unsafe, but thickness variations and installation issues caused pulsation in the front brake.
For example, when I first got my RX3 in June 2015, the brakes were weak and pulsed really bad. I lived with it for about 1500 miles. Finally I tried a series of quick stops in a parking lot, and that really helped bed them in and almost eliminated the pulsation. They continued to improve with use and by 2500 or 3000 miles, they worked really well with zero pulsing.
But 1500 miles is too long to live with poor brakes. If anyone is experiencing this, don't just live with it. You could skip all these steps and buy a new rotor and EBC FA185HH front brake pads. But these steps are cheaper, and honestly once bedded in, the stock brakes do a good job.
Proper bed-in
First, if the brakes are weak or only have a little pulsation, they just need to 'bed in'. This roughens up the smooth outer later on the brake pad and rotor surface. It also stresses the rotor under heat to even out installation and small manufacturing issues. This process is EXTREMELY important with the stock brakes since they take so long to bed in with normal riding.
A good bed-in process doesn't take long. Go to an empty parking lot and do several sets of 5 hard stops from about 35 mph. Let the brakes cool for a minute or two between each set. If your brakes start fading during the set (feeling weaker), give them more time to cool before continuing. The heat and cooling cycles help align the rotor and help correct any stretching due to uneven or improper installation at the factory.
Rotor and installation issues
Next, if your brakes are still pulsating, have a friend tilt the front wheel off the ground onto the side stand and spin it. The rotor should spin straight without any warping. A tiny bit of movement is okay. If it wobbles a lot, it might be defective, or it might just be torqued unevenly.
Then, using a cheap measurement caliper from Amazon or Harbor Freight, measure the rotor thickness at various points. If it's not the same thickness all around, you have a defective rotor. Call CSC for a replacement.
If the rotor has the same thickness all around, it was probably torqued incorrectly at the factory. Here's how to re-torque it correctly.
Rotor installation or re-torquing
- Remove the front wheel.
- Loosen all the bolts on the brake rotor and remove it.
- Clean the rotor and mounting surface with brake cleaner (don't use carb cleaner or any oil based cleaner) and reinstall the rotor.
- Finger tighten all the bolts until snug.
- Using a wrench, tighten each bolt one quarter turn in a star pattern ... After the first bolt, tighten the one across from it, then back on the opposite side, and so on until they are all tight by one quarter turn. The star pattern keeps the disc centered and the bolt forces evenly distributed.
- Don't fully tighten one bolt before moving on to the next one. Do a quarter turn at a time, nice and even.
- Don't go around the circle from one bolt to the next. This actually stretches the rotor disc on one side and compresses it when you get to the end, warping it.
- Continue tightening by one quarter turn in a star pattern until all the bolts are nice and tight.
- Reinstall the wheel.
Now do some more hard stops to reseat the brakes and rotor. If pulsation continues, call CSC for a new rotor. When it arrives, measure the rotor thickness to make sure it is the same all around.
Matching new brake pads with a new rotor
By the way, if you do need a new rotor, I would upgrade the front brake pads to EBC FA185HH at the same time. (They really are better brakes, and it's best to fit new pads with a new rotor.) Then follow the steps above to install it and bed it in. This should dramatically improve braking power and eliminate any pulsing effect.