BMW R1200RT/R1250RT Forum

Does anyone else have a problem with their 49L top-box sealing itself shut in the afternoon sun? 


Normally, mine opens just fine.  However, I few times I have gone out to my bike at 5:30PM after the bike has sat in the sun all day, and it is VERY difficult to open.  I can work at it and will finally hear a whooshing sound like it is sealed shut, when I do finally manage to crack it open.


Do I need to drill a vent hole somewhere?


Thanks for any suggestions.


Harold
'08 R1200RT

Hi Harold, it may seem like a dumb question, but is your box a new one fitted to an 08 bike or are they both 08 models and you bought it as a package? If it's a new box at that price I would be taking it back to the dealer. If an 08 package drilling holes maybe a solution but you compromise waterproofing. It's a nuisance the seals sound like they are going soft in the heat and sticking together. You could try drilling a hole in an inconspicuous place not effected by water ingress and stick a rubber grommet in and if the box sticks try releasing the grommet.  :clap:

Sun so warm it's melting the top box seal.  If only.  You would be better just replacing the seal as opposed to poking holes in the case.

hbjones wrote:Does anyone else have a problem with their 49L top-box sealing itself shut in the afternoon sun?

Is it a pre-LC 49 litre Top Box & what kind of ambient temperatures are you dealing with.

Mine was OK last year in Germany up to 39 deg.C.

Talcum powder the seals, worked on car doors for years and no residue from silicon.☺

Thanks for the replies and suggestions, everyone.  I will definitely try the silicone spray or talc methods before getting crazy with my drill.    I bought this bike used; so I don't know the exact history of this particular top box.  I just know it is a factory 49-liter BMW box.  I know it was sprayed to match the bike because the spray-job looks rather amateurish and is on my to-do list to sort out.


As far as ambient temperatures, I am in Phoenix, AZ, so I will be headed to 115-F (46-Celsius) within the next 5 or 6 months.  I have only had this bike since late November, and the two times it sort of suctioned sealed itself were at about 70-F (21-Celsius) with my helmet and gloves inside.   


I'll let you all know how the silicon or talc work out. 


My bike is in for her 24k mile service, so it will be a week or so before I can report back.  The real test will be summer in a few months, though.


Best Regards and thanks again for the many replies.


Harold

Air inside contracts causing a vacuum? If you do resort to drilling a hole, a small one should suffice <2mm and bottom of 'box nearest to pillion Seat?
Mine's the same top box, bought new in Feb for my 2013 twin cam. Not experienced the issue yet - but then, it's not been exactly warm since then.

I find it very hard to believe the box is so precisely built its capable of causing a vacuum. Drill a hole anywhere and water is guaranteed to find it.&nbsp; Just clean and lube the seal, A wipe with WD40 should do it.&nbsp;

Only time I've heard of that problem was with a large change in altitude
I think the poster lived in the States (if my memory is correct)

My Kappa top box used to do this on the other bike. You can see the same effect on a plastic bottle of cold water when it warms up - it contracts. This is usually an issue when the air inside the box was/is colder than the then ambient temperature, so yes, they can fit that well. I drilled a tiny hole in the Kappa box where no water could get in and it solved the problem.

Not to be too technical but you should check if the air is going in or out. If out, the problem is that the air inside is expanding under the heat and the seal is your problem. A hole won't help and may hurt as internal pressure helps you open the box. If the air is goin in, then the box is expanding in the sun and creating a vacume inside. A hole would then help, but he seal may still be part of the problem.

Before you attack it with a drill clean the rubber seal and apply a wipe of silicon.&nbsp; Problem should be solved