Ride Around Maine questions

Stephen!

Flivver Flyer
Premier Member
IBA Member
IBR Finisher
#22
The only real mechanical excitement was a malfunction of my aux fuel system. My first 3 fill ups of the aux went fine. But on the 4th it started peeing out the vent line. It filled and overfilled the small container on the vent.
Was the air temperature significantly warmer and the sun perhaps brighter during/after your 4th fill than on the three previous fills?
 

CB650F

Premier Member
#23
Congratulations! Sounds like quite the adventure. I’m glad you had better weather than me. Last time I was in Maine, i got rained on for a few hours. Ugh
 

OldCrow

Premier Member
#24
Was the air temperature significantly warmer and the sun perhaps brighter during/after your 4th fill than on the three previous fills?
My guess is that at Coburn Gore it was about 60F the last "successful" fill up and Medway was about 70F.

After much thought and research I think my mistake was just assuming that this venting was good since I've used this tank and vent on my 1981 R100RT many times without a hint of problem. But the Key difference was that on the BMW I have a Ride Off center stand and ALWAYS use it when refueling. So the tank was always level at fill and ride away.
I think a simple solution will be to route the vent line across the tank to the right side before down to the catch bottle. That way the line always has a point above the fill level. If I'd been thinking when I bought the tank I would have looked for one with the vent and cap on the right side.
I've been hunting for an anti-syphon/tip over valve but they all end up standing higher than my 3in peak. But by routing across tank then if the bike falls left the opening is up and if is falls right the intake is up.
Seems like this should work but I'm certainly open for suggestions. Thanks
OC
 

Stephen!

Flivver Flyer
Premier Member
IBA Member
IBR Finisher
#25
My guess is that at Coburn Gore it was about 60F the last "successful" fill up and Medway was about 70F.

After much thought and research I think my mistake was just assuming that this venting was good since I've used this tank and vent on my 1981 R100RT many times without a hint of problem. But the Key difference was that on the BMW I have a Ride Off center stand and ALWAYS use it when refueling. So the tank was always level at fill and ride away.
I think a simple solution will be to route the vent line across the tank to the right side before down to the catch bottle. That way the line always has a point above the fill level. If I'd been thinking when I bought the tank I would have looked for one with the vent and cap on the right side.
I've been hunting for an anti-syphon/tip over valve but they all end up standing higher than my 3in peak. But by routing across tank then if the bike falls left the opening is up and if is falls right the intake is up.
Seems like this should work but I'm certainly open for suggestions. Thanks
OC
My thought was that perhaps the fuel expanded in the heat and was pushed out through the vent. That happens occasionally on my setup with the vent being right below the cap and the cap being the highest part of the system. The filler tube enters the right side of the tank at the top edge. Even though I stop the fill about half the diameter of the filler tube, the fuel (through heat expansion) still manages to find its way up about three or four inches to the vent now and then.
 

OldCrow

Premier Member
#26
My thought was that perhaps the fuel expanded in the heat and was pushed out through the vent. That happens occasionally on my setup with the vent being right below the cap and the cap being the highest part of the system. The filler tube enters the right side of the tank at the top edge. Even though I stop the fill about half the diameter of the filler tube, the fuel (through heat expansion) still manages to find its way up about three or four inches to the vent now and then.
Oh I see what you are getting at. My habit is to run off the Aux tank first so thermal shouldn't ever be an issue. I like to get that weight off the back of the bike first.
 

Stephen!

Flivver Flyer
Premier Member
IBA Member
IBR Finisher
#27
Oh I see what you are getting at. My habit is to run off the Aux tank first so thermal shouldn't ever be an issue. I like to get that weight off the back of the bike first.
Ahhh... My setup does not allow that option. The aux drains straight into the main tank. If I neglect to close the valve on the aux or open it before I have drained 4.25 ga from the main, I end up with a rough running engine and the smell of raw fuel wafting about. My first experience with that was at 0230 in the middle of the Nevada desert. That was quite a butt clencher! :eek:
 

OldCrow

Premier Member
#28
Ahhh... My setup does not allow that option. The aux drains straight into the main tank. If I neglect to close the valve on the aux or open it before I have drained 4.25 ga from the main, I end up with a rough running engine and the smell of raw fuel wafting about. My first experience with that was at 0230 in the middle of the Nevada desert. That was quite a butt clencher! :eek:
My first aux setup was on a 2000 R1150GS and I had to count the bars on the fuel gauge before opening the aux valve and turning on the pump. So I know your pain :)
My BMW and GL are both carbureted so I Tee into the main feed lines and just close the main tank petcock or petcocks(BMW has 2). I just ride until power drops then open the main and feel the surge! I know they run lean for a few seconds but I doubt there is any real harm.
I'm thinking about a GL1800 to I've been giving some thought to its setup.

The only time I've had a fuel smell wafting about while moving was once when I was long into a ride and tired I umm, well, umm forgot to put the aux tank cap back on:eek: Luckily it was wedged on the pillion seat and backrest. No harm, don't think I even lost any fuel. Oh and once when the main fuel line out of the aux about 1in from the outlet developed a crack. Then I smelled fuel at a toll booth and raw fuel drip dripping onto the end of the right exhaust pipe. That will get you heart racing!
OC