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Old 08-19-2012, 06:24 PM   #15
ebrabaek
Beastly Adventurer
 
Joined: Jan 2010
Location: El Paso,NM
Oddometer: 4,347
Quote:
Originally Posted by JRWooden View Post
ebrabaek

Yes, that's really the way I would expect it to work ... !!!!

Hold a "slight" positive pressure in order to "force" generated gasoline fumes into the CC when the bike is turned off ...
and to "free-flow" at the slightest vacuum ... as that means the engine is running and the CC is being "purged" (and that the vent line on the bottom of the CC might be obstructed ... etc as a result of the on-board computer turning on the solinoid that applies intake manifold vacuum to the canister.

But ... if it really DID work that way then the "TEE modification" would not have been required to the canister drain line becuase having the "low down" drain line plugged by water or debris would not have resulted in a stalling problem ....

I've said this before, but I'll say it again anyway...

I'd pay some serious money to share an evening's worth of beer with the German design team and hash some of this stuff out. Those guys are plenty smart or they wouldn't work for BMW ... we're kind of like the blind men and the elephant if you know that old joke....
Ha ha.... Beer with a German... I see an iceberg ahead....... Yes there is a need for the T... well...at least a vent...not from the tank. You see if the only vent into the CC was through the tank....when the purge valve would open and suck in the fumes, it would cause the engine to run too lean..... so they put a vent line down in front of the rear tire.... wonderful.....now the motor is breathing in a mix of tank fumes.....and fresh air...when the purge valve opens. Awesome.... But when the Germans tested this.... they did so i Denmark, where the weather is always sunny 360 days of the year...... Ha ha Joke.... but seriously....no rain....because when it was driven in the rain, and the purge valve opened.....fresh air from the vent in front of the tire was sucked in rather than the over pressurized tank ( remember the tank has to produce about 4-5 psi to vent.... In rain.......perhaps...cold weather....that is not likely to happen....therefore.....the little tube in front of the tire now is a vacuum cleaner.... whater is now sucked up....and into the intake manifold...and combusted.... well...trying to combust.... result....Stalling. Solution...either take out the one way check valve, and risk offending the Bavarian engineer who created the system...... or simply put a T so it now will suck from under the seat.....well ....we know the results. Reason for the hose going down..... You have all these people who want to maximize the endurance....and tip top off the tank....on the side stand...... Awesome.....but the fuel has to go somewhere....and gravity rules.....fuel with expansion now enters the CC...( Charcoal Canister)....and drips down in front of the tire.....Nice. The short and great fix would simply have been to remove the Check valve..... along with installing the T.....so fuel can still drain down.....and when driven in water.....the under the seat hose vents, when water enters the down pipe. OR.....Simply leave it like the Bavarian's did for them self... ( smart people)... simply don't install the CC.... Ha ha.... they are still laughing at us Yanks..... or in this case Danes......ehhh...uhmmmm... living in the US.
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