R1100RS Charcoal Canister

My 2000 R1100RT was totaled 10 days ago (while parked). Insurance company writes me a nice check, and this weekend I found a 94 RS in pristine condition. 50K miles, has Ohlins and assorted other nice farkles along with every service record since new. And it was so clean you could eat off it.

Now, the problem. The previous owner removed the charcoal canister and the lines are just zip tied to the rear peg bracket. I have owned it since Saturday and after every ride I get a quarter size drip of gas on the ground. To make it worse, when I park it in my air condition garage over night I get about a 5 inch diameter pool.

I'm sorry but this is totally unacceptable. I have a spare canister. Should I just put the thing back on? Is there going to be any issues? The canister is off my RT but I'm just guessing they are all the same in that year range (correct?). It's a great bike but I can't deal with a gas leak.

I don't know if the canisters are the same but you can figure that out at the MAX BMW parts site. You shouldn't put it on yet though.

There are two vent lines inside your tank that exit through a metal plate in the side of the tank. One goes to the filler neck to drain water from the outside. The other goes to an anti tip valve at the top of the tank. Assuming that your tank is not over full, my guess is that inner vent line is leaking inside the tank. You need to have this figured out and repaired before putting the canister back on.

If you search this forum you can find a lot about the repair.

gas is not leaking solely because of cannister removal (mine's gone, has never leaked). most likely, filler neck has been drilled, or (possibly) cannisterectomy was not quite completed. with the filler neck having been drilled, they will leak when on sidestand with full tank. so- either don't park it with a full tank, or use the c-stand to do so.

Take a look at the can removal procedure - I just did mine. Doesnt sound like they capped off one of the lines correctly.

I love the look without the can - my vote is - KEEP IT OFF!

http://www.ibmwr.org/r-tech/oilheads/cannister_horn.shtml

leak

Bad line inside the fuel tank. If you replace the canister without replacing the bad line, you will just kill your newly installed canister. The canister is there to collect vapor, not raw fuel. Yes, it is intended to intercept an 'overfilled' condition, but I would bet you haven't done that, now have you?
Be sure to buy the necessary 'safe to be submerged' fuel line from Napa (or your dealer).

Does a R11RS even have one?

I have a 95 R1100RS and have never seen one on my bike or in the parts micro fich thing iee.

My vent tubs just run down between the swing arm and right foot peg mount.

Jambx said:

Take a look at the can removal procedure - I just did mine. Doesnt sound like they capped off one of the lines correctly.

I love the look without the can - my vote is - KEEP IT OFF!

http://www.ibmwr.org/r-tech/oilheads/cannister_horn.shtml

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Thanks, this is excellent. I'll do a reverse check of the previous work; I would guess something along the lines of the comments here has occurred.

By the way, the bike has not had a full tank yet (probably less than half).

On a complete different note, I love this bike so far. I sold my CBR900RR to get the 1100RT.....I wanted something I could ride to work comfortably every day and possibly do some real miles. The RT was great and I dealt with it's "largeness" just fine. But I think this RS is what I was really looking for.

[QUOTE
On a complete different note, I love this bike so far. I sold my CBR900RR to get the 1100RT.....I wanted something I could ride to work comfortably every day and possibly do some real miles. The RT was great and I dealt with it's "largeness" just fine. But I think this RS is what I was really looking for.


I could not agree with you more - I was looking for something more comfortable than my Ducati M900 - always loved the look of the Boxer BMWs and started looking at the RT but something just didn’t seem right. Too much fairing, too heavy - it just wasn’t me - than I found out about the RS - it was perfect in my eyes - sporting yet offered some protection and 2 up was a dream compared to the Monster!

Although I still have the M900 for those days I feel like a kid again.

It shouldn't be too hard to fix. You just need to pull the tank, flip it over, pull the fuel pump plate, and troubleshoot the lines. While you're doing it, you might want to consider installing some quick disconnects in the fuel lines. You can buy them from beemer boneyard. They're a little pricey, but they're very trick, and stout.

While you're doing that, you might want to consider externalizing your fuel filter. Once you see how hard it is to pull your tank, you need to consider the thought of doing it on the side of the road to change a bad filter. Huge PITA. If you move the filter outside the tank you have a much easier time changing a filter.

Also, once you have all this sorted out you still can't simply fill the tank and park it for the night. It will leak. You need to get gas 10 miles or so from your destination, or leave a little air gap at the top of the tank.

Jambx said:

[QUOTE
On a complete different note, I love this bike so far. I sold my CBR900RR to get the 1100RT.....I wanted something I could ride to work comfortably every day and possibly do some real miles. The RT was great and I dealt with it's "largeness" just fine. But I think this RS is what I was really looking for.


I could not agree with you more - I was looking for something more comfortable than my Ducati M900 - always loved the look of the Boxer BMWs and started looking at the RT but something just didnÔÇÖt seem right. Too much fairing, too heavy - it just wasnÔÇÖt me - than I found out about the RS - it was perfect in my eyes - sporting yet offered some protection and 2 up was a dream compared to the Monster!

Although I still have the M900 for those days I feel like a kid again.

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Damn, we should be hanging out!

I've got a Monster too and instead of the nice TR6 I see in the background, I've got an Alfa Spider. Too funny..

The Monster...

What would happen if you just plugged the line that is dripping?

Bmandiego said:

What would happen if you just plugged the line that is dripping?

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That is one amazingly good question that I almost didn't dare ask for fear of being beaten over the head with a charcoal canister.

rd400racer said:

That is one amazingly good question that I almost didn't dare ask for fear of being beaten over the head with a charcoal canister.

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too funny. lol

Bmandiego said:

What would happen if you just plugged the line that is dripping?

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Eventually the line will deteriorate and start leaking again. You will have a drain line sitting there full of fuel over a hot exhaust/engine while you wait.

My 95 GS had a similar problem after I replaced the fuel filter. Somehow during the job I pinched one of the internal vent lines and it cracked and started leaking. Of course I discovered this after filling the tank all the way. It started as a drip and turned into a pretty steady flow. Drained and pulled the tank again and replaced all the internal rubber lines, even the expensive little U line. Problem solved.

I also replaced the external drain lines just for good measure.

While your in there you might as well change the fuel filter and sock and put on some new fuel lines and quick connectors. All the lines in the tank need to be rated for submersion in fuel.

Especially if you keep the bike inside a garage, I would keep the canister for sure. Many people really don't understand what the canister does and doesn't do. There's no reason to take it off unless its damaged or you are vain about the appearance of the bike.

The problem is a bad hose, which will be present with or without the canister.

R1100 RT and RS canister info

The BMW factory parts used for the charcoal canister system are the same for the R1100 RT and RS. This includes the canister itself, the tank breather valve, and the hardware to mount the system. I confirmed this by comparing the parts diagrams for the RT and RS on the Max BMW website.

Interestingly, the filler necks for the RT and the RS are different, the RS is much deeper than the RT.

Two lines run from the filler neck inside the fuel tank: the vent line and the drain line (the latter is the little round opening you can see after you open the fuel tank lid with your ignition key).

Both the drain line and the vent line exit the fuel tank at the metal plate on the bottom inside of the fuel tank--same plate used for the fuel pump. The drain line dumps onto the ground near the right rider peg. The vent line runs back to the charcoal canister.


If the canister Evap system has been removed, the vent line is usually re-routed together with the drain line to below the right rider peg area.

Next, if you fill the tank (canister-removed bike) with fuel and allow it to sit in the hot sun, fuel expansion may cause fuel and fuel fumes to vent out the vent line. If your RS filler neck has been replaced with the shorter RT filler neck and you fill the tank to the filler neck and then park the bike in the sun, it's sure to vent fuel onto the ground.

You can prevent venting fuel by blocking the vent line by inserting a bolt or other such into the end of the vent line. Problem with this is the tank has to way relieve either positive pressure(expanding fuel/air) or negative pressure (fuel decrease due to consumption)

Another fix I've seen is placing a one-way check valve at the end of the vent line that allow air to enter the tank as the fuel level drops. However, there is no way for pressure building up in the tank to be relieved--tank can equalize pressure only one way: IN. A full tank placed in the hot sun has build up a surprising amount of pressure. The 96 R1100RSL I recently bought had this "fix" and when I opened a full tank that had been sitting in the sun, there was a rush of air followed by fuel flowing out of and over the tank. With a little research I also discovered the the original filler neck had been replace with one from an RT, making it very easy to overfill the tank using up the expansion space.

Finally, if (canister removed) you have a proper RS filler neck and do not overfill the thank, there should be enough expansion room that no fuel vents (drips/runs) out the vent line, perhaps some fumes, but not fuel. If you are getting a drip from the vent line and have not overfilled the tank, the first suspect, as AntonLargiader points out in the post above, is the vent line inside the tank; this line may be leaking need to be replaced.

One moral of this story is that it is sometimes unwise to let a full fuel tank sit in the hot sun. Another is that before you make modifications to your beloved machine, consider the unintended consequences.

New to RT

rd400racer said:

On a complete different note, I love this bike so far. I sold my CBR900RR to get the 1100RT.....I wanted something I could ride to work comfortably every day and possibly do some real miles. The RT was great and I dealt with it's "largeness" just fine. But I think this RS is what I was really looking for.

Click to expand...

I came to the an 04 RT and subsequently an 97 RT from a ZX9R and have really enjoyed the ability to ride all day and long distances between fill ups. The bike carves handles well, carries a ton of stuff, and is comfortable. Win, win, win!!!

Just installed Ohlin's front and rear shocks, so I'm excited to dial those in and hit the corners.

Enjoy!