BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

Hi guys,

Well I finally did it, I dropped the bike the other day on its right side.
Fortunately the cylinder protectors took the brunt of the damage so i got lucky in that regard.

My issue is that the next morning I came out to look at the bike and noticed a puddle of what I now believe to be
brake fluid near the rear wheel. I looked at the rear brake and clutch and didn't notice any wetness or residual on those
areas. The only thing I noticed was some wetness on the middle hose of the pic I am including in this post.

Is this something I should be concerned about? The bike was on its side for only a few seconds. I obviously need to
replace the brake fluid that came out, but should it come out of this hose at all? What is the hose used for?

Thanks for the help

Are you sure it's not just some fuel from the vent line? Trace the 'wet' hose back to it's source (you only need a torch) and confirm what it is. And have a good look at the 'leak'. The brake reservoirs have sight glasses, so you should be able to see them at their correct fill levels. Unless the bike has ABS where there is an ABS unit under the tank (I think). I doubt that area would spring a leak.

It would be rare for you to get a brake leak after a drop unless you broke a line or reservoir. I would suspect it's a fuel overflow or maybe even some accumulated breather oil from the airbox, particularly as you are showing vent and overflow tubes in your pic. The only other one might be the battery vent, if you are running an older liquid lead-acid instead of a gel type.

I doubt it's a problem, but check anyway.

Thanks for the advice MIXR. I guess it could have been fuel, but it lacked the smell and seemed more viscous than fuel, but it did sit on my garage floor all night.
I'll do some more detective work. The bike does have ABS, but if something broke in the ABS unit it would be all over the frame of the bike and I didn't see any residue.

Sorry to hear of your misfortune. You know what they say,"There are those that have, and those that will!"

MIXR said:

...(you only need a torch)...

Just a reminder that where Mick comes from "torch" is a flashlight!
Wouldn't want you to realize it was gasoline as you are flying through the air after the explosion.

And since it doesn't smell like gas he's probably right and it's probably some spilled battery acid. If that middle hose is slightly smaller in diameter than the other two (it's hard to tell in the pic) then it's the battery overflow drain.
You can sprinkle some baking soda on it and it will fizz as it neutralizes that strong acid.

Thanks Rich - The Queen's english gets me into all sorts of trouble with you lot over the pond!

Also found this in an old thread.

Re: Gas Tank vent hose
by Sunbeemer » Mon May 19, 2008 12:26 pm

It could be:
1. Gas tank rain/overflow vent hose
2. Charcoal canister vent hose,
3. battery acid vent hose.

The first two are the same size hose and bigger than the third one, which is often disconnected when a maintenance-free battery is installed (since they have have no acid-overflow vent).

If it is:
1. rain or a gas-splash during fuelling will dribble out the bottom of the tank onto something under there.
2. if charcoal canister gets full of fuel it may dribble from the front of the canister onto something back there (unlikely).
3. if a wet-cell type battery is overcharged and dribbles acid out the vent it will get on something under there and MAKE A MESS!

None of these things are ride stoppers, but find it and fix it when you get a chance.Rich
Going to the sun on a Blue '02...
Sunbeemer
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Re: Gas Tank vent hose
by Oilhead » Mon May 19, 2008 2:35 pm

Thank you Sunbeemer.

It is not the charcoal canister hose as they are intact. Yes it is much smaller in diameter than the canister hose(about 40% diameter) so it's very likely the battery acid vent hose. I do recall that the battery was a fully sealed unit when I installed it a few months ago. Is there even a place to connect the acid vent hose?2002 BMW R1150R
2004 Honda CBR600RR
2006 Kawasaki KLX250S
2008 Ducati Hypermotard
1996 Ducati 900SSOilhead
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Re: Gas Tank vent hose
by awagnon » Mon May 19, 2008 9:09 pm

Oilhead wrote:
Is there even a place to connect the acid vent hose?

Probably not, if it's a maintenance free battery. I just removed the hose, but might be wise to leave it in case you need a battery in an emergency on the road and all you can get is a standard flooded cell battery.Al
Ogden, Utah

first, your bike is pathologically clean right there. Is there anything else wrong?

second, y'all got me curious so I went down to slumbering Stella! and checked out those lines.

The rear most goes to the charcoal canister, actually it EXITS from the CC. The CC also receives a vent hose from the tank The front one goes into the guts of the engine and disappears from tracing it, but it goes to the center above the crankcase.
The one in question, the middle one is one of the two vent hoses that go to and from the tank, prob for overflow. If the bike were on its side gas could slosh up to its port and then be visible there at the exit of that hose.

Third, and I could be wrong, it would not make sense to have a true "vent" hose for a hydraulic system like the brakes; maybe a pressure relief valve-and probably not even that, but not an atmospheric pressure vent.

That it didn't smell to you like gas probably falls into the "isn't that interesting" category, and not much should be made of that. Maybe there was a little water in there, maybe for the length of time it sat the aromatics of gas dissipated.
That it felt a little greasy, that could be gas sitting in a rubber hose, exposed to road grime, and dissolving into an oily residue. Don't know.

I would check the rear reservoir to be sure it is filled properly (read: enough and not even an imagined smidge low), and you may have to remove the side trim to adequately examine it, unless you have long skilled fingers that can remove that ill-placed cap. Be anal about its level and don't spill any brake fluid. Keep an eye on your ABS light on the dash during the next few miles.

My gut is some gas spilled out and you're fine, but imo you have to check the fluid level.

John

Thanks for the help guys.

Yeah I knew that a "torch" is a flashlight. Thanks for the reminder though.

I got lucky in that I was making a turn and so it went down on the cylinder protectors. The brake lever got a few scraps but besides that no damage.
Replace the protector, brake handle and you wont be able to tell it happened .

I haven't had a chance to look at the bike, been to busy with work. I don't think it was battery acid, b/c I stuck my finger in it to smell it and I haven't had any kind of reaction.
Unless I'm mistakenly assuming that the battery acid would at least burn my skin.

It sounds like I'm just going to have to pull the seat and get a good look.

I'll keep you informed as to what I find.

And no Dr. nothing else is wrong. My bike only has 6800 miles on it . The guy I bought it from was meticulous with his cleaning