Broken Windshield Arm R1200RT

[Kanga]

I noticed on the way home that the windshield was a bit wobbly, so on closer inspection once I got home the left arm that raises and lowers the windshield has snapped off, right up the top. I do run a Cee Bailey screen and wondering if this has been partly to blame.

 

Of course will replace the original screen before taking back under warranty, as I don't need any hassel from BMW. The bike has only covered 7000k's. Anyone else had similar problem??

 

thanks

Kanga

[graemer57]

Had my bike serviced last week. One of the mechanics remarked that they had seem quite a few R12RTs lately with broken windscreen arms where larger aftermarket screens had been fitted. Maybe the design is marginal and cant take increase in pressure that occurs with larger screen?

[gettysburg]

I guess a market just opened up for someone to make stronger windscreen arms.

[loujack]

WOW. Certainly some food for thought on aftermarket windscreens installation. Thanks for the tip and I hope you are able to get the problem rectified under warranty.

[ADulay]

Just to tack on to this thread, I was wondering if there was any "upper speed limit" for running with the stock windshield fully extended.

 

I've had it up to 110mph and then started thinking about how much pressure may have been on those arms.

 

Any ideas?

 

AD

[velomoto]

Anyone takin' odds on whether this will amount to a recall or not???

[St0nkingByte]

Well there are a bunch of variables. Temperature, altitude, current barometric pressure, the surface area of the windshield, angle, a headwind, etc but straight from the Department of Made Up Figures where we are right exactly 93.8% of time (give or take 94%) I'll take a run at it. If I remember correctly what we're talking about is drag, or the pressure put on the windshield. Borrowing heavily from here:

 

http://www.madsci.org/posts/archives/mar98/890199316.Ph.r.html

 

because that example is simplier than most others we can make some wild guesses.

 

Drag = Drag Coeficient * Dynamic Pressure * Area

 

Here's what these terms mean (again stolen from that page):

 

Drag - a force, in pounds

Drag Coeficient - a special coeficient that is different for different shapes

Dynamic pressure - a term for this: 1/2 * density * (velocity)^2

Area - area, in square feet, that is perpendicular to the flow

 

The density of the atmosphere at sea level is about 0.00238 and the velocity is in feet per second (which gets squared). At 110mph velocity is 110mph X 5280 feet / 60 / 60 = 161.3 feet per second.

 

The drag coeficient for a flat plate that is approximately square (that is, its length is about the same as its width) is 1.16 , 1.12 for a circular plate and about 0.63 for a circular cylinder. Lets figure the windshield is somewhat more aerodynamic than a flat square plate but not as good as a cylinder, so lets call it, um 1.0. The area of the stock windshield is roughly 3.5 square feet of surface (another wildly inaccurate guess)

 

So here comes the formula:

 

Drag Coeficient: 1.0

Dynamic pressure: 1/2 * 0.00238 * 161.3^2 = 30.96

Area: 3.5

 

Drag = 1.0 * 30.96 * 3.5 = 108.36 lb

 

Which doesn't seem too far off to me. 110mph is pretty darn windy. Obviously if you add an aftermarket shield you increase the surface area. The 3.5 in my wild guess formula. You can see from the formula that even if my numbers are crazy wrong (which they probably are) if you change the first number (drag coeficient) with a larger/flatter aftermarket shield and you add surface area (the 3.5 number in my example) you can really jack up that drag number quickly. For example:

 

Drag = 1.05 * 30.96 * 4.5 = 146 lb

 

Of course 110mph is a great speed to use for the example because its so high

[MooreDriven]

I don't have my manual in front of me, but I think it states you should not adjust the windshield above 30 or 40 mph. I even had the dealer tell me not to adjust when above 40 mph. He noticed I had the Cee Bailey's and made the comment.

 

Frankly, I think it's a really bad design if you can't adjust while moving. Typically I leave mine in one position, but if it starts to rain, I'll raise it up. Surely the egnineers consider this possibility when they decided to add an electronic motor to the windshield!

[Guest]

You can get 110mph air speeds if riding 70mph into a 40mph headwind.

[graemer57]

I ran up to 132mph with the screen full extended with no problems. Felt no different to me than rolling along at 80-85 mph but my wife said buffeting was much more severe for her on the back, and she usually finds buffeting to be less severe with the screen up at lower speeds

[Kanga]

Just an update, I now have to wait at least 3 weeks as the arm has to be ordered from Germany, I asked them to order both sides as most likely the other will break before they get the new one in.

[KiwiAdventure]

I noticed on the way home that the windshield was a bit wobbly, so on closer inspection once I got home the left arm that raises and lowers the windshield has snapped off, right up the top. I do run a Cee Bailey screen and wondering if this has been partly to blame.

 

Of course will replace the original screen before taking back under warranty, as I don't need any hassel from BMW. The bike has only covered 7000k's. Anyone else had similar problem??

 

thanks

Kanga

 

I don't like people like you that rip the warranty system off. You fitted a bigger non BMW screen and the arm is now broken and you blame BMW.

[cjmkerns]

KA,

 

I'm surprised. Someone posts an action you disapprove of, and, rather than note you don't think that it is right, you state on a public forum that you don't like the person. Separate the two, he could be a nice guy. I have good friends who have done things I disapprove of. Come to think of it, I've done things I disapprove of.

 

On another note, we've been hangin' barn doors on the previous itterations of the RT with no problems. Perhaps there is indeed a weak link in this one's design. I suppose we'll have to keep an eye on it.

 

 

Regards,

 

Carl

[onedae]

WOW - here is a guy with an open mind !!!

[Kanga]

Hi KA

 

Maybe you can point out in my post where I blamed BMW, I had another read of it and can't see where I have. Maybe you should actually read what is written and not what you think has been written.

 

And for what it is worth the windshield that I use is no bigger then the larger windshield that BMW supply.

 

It's always nice to meet someone who's perfect.

[Boffin]

This is not aimed at anybody in particular, it is just a reminder to keep discussions civil so we can all benefit from them. The alternative is to shut down a usefull thread.

 

Thanks for your understanding folks

 

Andy

[black99S]

Perhaps as suggestedon on the 'does anybody like the RT seat' thread, a Class Action Lawsuit should be entertained

Seriously, I'm going to keep an eye on mine and thanks for the information on breakage. I'm enjoying liberal use of the screen button at all speeds and in all conditions.

[Mark_C]

When I fitted my Cee Bailey screen I noticed that the mounting holes did not line up as accurately as the standard screen. It's possible that there could be some sideways stress on the arms as a result. Could this have caused the failure?

[RT_Pilot]

While I don’t condone what KA is saying, it raises an interesting point. Maybe Cee Bailey should be accountable for such a flaw, if that is indeed what caused the problem? Just a thought…

[graemer57]

Maybe I am missing the point here? With no disrespect to the guy who made the original post, I am sure I am not the only one who was surprised to read what you wrote in the first place (maybe a case of some things best left unsaid??) You do leave yourself open to critiscism if you say you have fitted an aftermarket screen and the screen arms have failed but you are going to refit the original before making a warranty claim as you " don't want any hassel from BMW". By doing that you are admitting to yourself that the aftermarket screen may be the cause of the failure.. and if it is why on earth should BMW bear the cost of repair. In the end all such costs will eventaully be charged back to the owners of BMW bikes by an increase in prices, after all BMW are not a charity! As for stating it is the same as the BMW larger screen that is a red herring, and sounds like an attempt at self justification. If the arms fail while you use ANY BMW screen it is fair claim under the warranty but not if it isnt a BMW screen.

 

Perhaps a more pertanent extension to this thread would be to find out if the arms have failed on any bikes just using the BMW screens...then we would truly know if there is an inherent design fault.

[RT_Pilot]

I think the point is that their may be a problem with the windscreen mechanism whether caused by an after market screen or not, it is good to know. Beyond that “people in glass houses shouldn’t throw stones”…

 

I appreciate the heads up. I’m to busy guarding my own virtues to worry about anyone else’s. I would like to know what happens with the problem.

[Rusty1945]

Maybe I am missing the point here? With no disrespect to the guy who made the original post, I am sure I am not the only one who was surprised to read what you wrote in the first place (maybe a case of some things best left unsaid??) You do leave yourself open to critiscism if you say you have fitted an aftermarket screen and the screen arms have failed but you are going to refit the original before making a warranty claim as you " don't want any hassel from BMW". By doing that you are admitting to yourself that the aftermarket screen may be the cause of the failure.. and if it is why on earth should BMW bear the cost of repair. In the end all such costs will eventaully be charged back to the owners of BMW bikes by an increase in prices, after all BMW are not a charity! As for stating it is the same as the BMW larger screen that is a red herring, and sounds like an attempt at self justification. If the arms fail while you use ANY BMW screen it is fair claim under the warranty but not if it isnt a BMW screen.

 

Perhaps a more pertanent extension to this thread would be to find out if the arms have failed on any bikes just using the BMW screens...then we would truly know if there is an inherent design fault.

I couldn't agree more with this point. When you mod your bike, you also have to realize that there may be unforeseen consequences; no aftermarket or even oem for that matter can anticipate all the variables that can occur with every piece of added gear. As far as I know, this is the only report of a broken shield arm. Now how many of us have aftermarket shields with no problems? Context, context.

[russg]

While I think it may sound like a shady practice to swap a part back before requesting warranty service it certainly will save you some time. You see, the manufacture, in this case BMW is required by law to repair the part under warranty regardless of the windshield that is attached. It is BMW's right to review modifications and aftermarket parts to determine if they caused or aided in causing the failure. If your dealer says that the aftermarket part caused the failure then you have a right under law to request a third party evaluation. A reputable aftermarket manufacture will stand behind you during a warranty claim. That is if the aftermarket manufacture certifies the part not cause problems. If you buy parts from a manufacturer that are not certified for your vehicle then you are on your own and swapping the part out and making a claim is certainly shady business practice; something you wouldn't want pulled on yourself.

 

In this case, if CeeBailey warranties their part and certifies it as fit for use on the vehicle then you could take the bike in with that part installed and the dealer should replace the part. Now, for the sane in the room, it is likely that the dealer will point to the aftermarket part and you could find yourself in a battle to get your bike fixed under warranty. While it is likely you will win with a certified part, you will likely be without your bike for a good while and be tied up fighting the manufacturer while you could otherwise be riding.

 

I would also report the arm failure to CeeBailey and request written statement as to the screens fit for purpose and it they warranty it from breaking the lift arms.

 

I'm on the fence on this one, given a quality part from a reputable aftermarket dealer I would likely do the same thing to avoid being hassled even though I know I'm right.

 

YMMV

 

Here is a link discussing the Magnuson-Moss Act which protects your rights for warranty claims. Of course, this is US centric, sorry rest of the world but you likely have similar protections under your local laws.

[RT_Pilot]

I was going to say, our broken part is “down under” where toilets flush in the opposite direction… May have there own laws about these things.

[russg]

Yes, as you can tell from my post the thought only occured to me at "submit" that more people live outside the US than in it. I did save face at the end though. Good save?

[Highway41]

Feel like I'm hijacking this thread, it has gone so far afield.

I would like to know where the arm broke? Was it upper/lower eyelet, upper or lower arm?

I have an Aeroflow on my RT which "lays" down at speed implying more load than the stocker.

Thanks. Bill

[Kanga]

Feel like I'm hijacking this thread, it has gone so far afield.

I would like to know where the arm broke? Was it upper/lower eyelet, upper or lower arm?

I have an Aeroflow on my RT which "lays" down at speed implying more load than the stocker.

Thanks. Bill

 

Hi Bill

 

It's the upper arm , and it broke just below the upper eyelet.