poor performance after fueling

[Mr. Chris]

Hello,I am new to BMW and new to this forum. I have a 09 with 4500 miles and I've only fueled three times but each time the bike ran very poorly for 5-10 miles after filling up. Also smelled some strange fumes coming from exhaust. The manual says not to fill past collar in tank and I've tried not to do that. Any help? Thanks in advance.

[marc]

Welcome to the forum and where are you? If you have a US bike you may be seeing the result of the purging of the evaporative canister, although noticing the purge should be a somewhat rare event, not after ever fill up.

I take it you are not the original owner. Any idea if the PO made any modifications to the fuel system?

[pdxrmccgs]

Ethanol and its affinity for water are often touted as a intermittent
rough running cause.

Bad exhaust smell can be catalytic converter chemistry. C/c needs to
get up to certain temps to run correctly.

Welcome to the forum.

[Mr. Chris]

Thanks guys. I am second owner, and first did not alter bike. I found some info on an old thread that was about this very problem. I'l try drygas first then less fuel at fill-up. Thanks for the welcome.

[Southern Cross]

How did the bike run before re-filling? Over filling the tank has never affected any bike that I have owned.

[Fudmucker]

Did you refuel at the same source? (gas station)
Did it stay away for the duration of that tank of fuel?

If so, I would suggest that water in the fuel is likely.
Unlike the old Airheads, the "no petcock" newer bikes make it very difficult to drain a sample to test.

By the way, never refuel if the gas station is receiving or has just received a delivery of fuel. The bulk supply into underground tanks stirs up sediment and water in the bottom of the storage tank. (Tip from a gas station owner)

[Willie B]

I have a '09 GS and have experienced this same problem when filling the tank to the top of the neck. Fuel runs down the overflow to the evaporative canister and causes the bike to flutter for the next several miles. I removed the evaporative canister and rectified the problem. If you don't want to remove the canister, don't fill the tank to the top and the problem should rectify itself.