2017 r1200 rt warped rear brake rotor

[mxsx337]

Mechanic told me my rear brake rotor was/is warped. My bike has 41,500 miles -- is this a common or known problem on the wethead RT's? I'm more than a little suspicious because the same mechanic said I needed new rear pads as well and I had those replaced (different shop) at 35,000 miles. There was no mention of warped rotor by the first mechanic (35,000 miles) nor did I ever notice any pulsing or vibration when braking -- of course I don't use the rear brake all that much, trail-breaking or mostly slow, parking lot maneuvers, etc. I'm hoping for a quick response here because the mechanic wants an answer: Thanks!

 

[etiennelau]

I don't see how the rear rotor would warp....I am not a believer in warped rotor concept. Ask the mechanic to show you what they're seeing to indicate warped.

 

[BC1100S]

I once bought a used motorcycle which had a "warped" rotor. I could feel it when I test rode the bike. It does happen. Typically one would identify high and low points on the rotor face.

Ask your mechanic what the run out is. It's easy to measure.

 

[brownie0486]

I warped a rear rotor on my 2012 GS on the way back from Alaska [ 8K mile round trip in 3 weeks ]. I could feel it, but still had plenty of braking power. Rode it that way from Calgary to Az. [ another 2500 miles like that ].

Mechanic suspected I picked up a stone that lodge between the rotor and brake pad which heated the rotor till it warped.

It can happen.

 

[joeintus]

You use your rear brake every time you brake. It is integrated with the front brakes and is used whenever you pull the handbrake lever.

 

[mxsx337]

Thanks to all who responded!

I feel better about the situation because of all your helpful info: I contacted the mechanic and gave him authorization to replace the rotor and pads. He assured me (and I do have some trust in him) that the parts needed to be replaced. He is going to keep the pads and rotor to show me the "hot spots" and pad wear. Thanks again! In a couple of weeks I'm taking the bike up to Green Bay, WI to see a Packers game -- my first at Lambeau Field -- I was born and raised in Milwaukee, so a big fan!

 

[rtwiz]

I don't see how the rear rotor would warp....I am not a believer in warped rotor concept. Ask the mechanic to show you what they're seeing to indicate warped.

You can warp a rear rotor by resting your foot on the rear brake while you ride. The bike can do it on its own if there's air in the rear brake line.

A friend picked his K1200RS up from a dealer service, went about half a mile on it and was stopped at a light. The guy next to him said "Hey, man, your bike is on fire." He looked down and his rear brake was in flames. He rode it back to the dealer. They tried to deny the claim!!! (They're out of business now, btw) Anyway, they didn't bleed the rear brakes right or something. Not only were the rotors warped, the brake lines were burnt and had to be replaced. I think the pads too. Calipers were rebuilt.

Rear brakes can get hot and warp if they're applied continuously...either on purpose or by accident or by wrong maintenance.

Discs on newer BMW bikes "float". If they warp just a little, you won't feel it. But, if they warp enough, it will be felt through the lever and braking will be uneven. Eventually, it needs to be fixed.

As a youth, I crashed a motorcycle bad and gave them up. I did track cars instead. Brakes on heavy-ish street cars on a race track are a whole study...Much more heat there than motorcycles make...and worse air-flow. So, you have to learn things if you want to go fast for any length of time. One of the basics, if you get your brakes hot, don't sit still with brakes applied. That's a classic way to warp rotors. If you can keep the rotors moving a little it will keep the heat more even and they're less likely to warp.

This sort of stuff is good to have in your head when your ride. If you have a session where the brakes get used really hard and may be quite hot, think about that and try to avoid just stopping, especially stopping with brakes applied...You're squeezing the hot pads against the rotors and they're much hotter than the air around the rest of the rotors. The uneven temp will try to warp them.

This is harder to do on a motorcycle than a sports car, but it's not impossible. Think like your motorcycle.