Fuel pipes- Stupid questiony

[Crapaud]

Hi
Just replaced the fuel pipes on my '93 R100GS.
There are two fuel taps, one on each side. Instead of simply going to each carb, they have a T junction piece which goes under the airbox.
What is the point of this?
Would it not be simpler, and in keeping with airhead style, to simply go direct to each carb?

 

[SBD]

My Guzzi LeMans has an “X” under the tank which allows either side of the tank to feed both carbs.

I guess you could treat one side as a “reserve reserve”, but I suspect it’s intended to ensure no issues with starvation.

 

[Teamin]

As above. You have two sides to a tank as it sits over the frame.
The link pipe it to balance both sides of the tank.
From memory, on the 1100GS if you run out of fuel, you can tilt the bike and get a bit more out tof the side that isn't directly connected to the fuel outlet.

 

[scooter paul]

Hi
Just replaced the fuel pipes on my '93 R100GS.
There are two fuel taps, one on each side. Instead of simply going to each carb, they have a T junction piece which goes under the airbox.
What is the point of this?
Would it not be simpler, and in keeping with airhead style, to simply go direct to each carb?

Other owners of these fine machines have asked the same question. The fuel tank ‘folds’ over the frame top tube. If you didn’t have the cross over fuel line one carb could, in theory, be starved of fuel when you get very low. It allows the fuel to balance out from one side to the other. The earlier G/S and ST didn’t have the same need as the tank was much shallower in construction. Only one tap fitted to these servicing both carbs.

 

[Bubb]

It’s so you can have two separate reserve tanks….. when your bike goes onto reserve….just turn one tap, and you get a certain amount. When that drains, turn the other tap and you have a second reserve, and a reminder that you REALLy need to find a petrol station sharpish.

 

[Santa-2512]

Dont we know it !!

Coming back from Sids this year, the fuel stop I chose on the page, had no fuel and a frantic hunt for a petrol before I ran out. 20k range - and nearest fuel 16k. Eeks

 

[theoneandonly]

It’s so you can have two separate reserve tanks….. when your bike goes onto reserve….just turn one tap, and you get a certain amount. When that drains, turn the other tap and you have a second reserve, and a reminder that you REALLy need to find a petrol station sharpish.

going down the m/way at 90 , you only have to take 1 hand off the bar , turn the lhs to reserve , zero the trip , stop at the next petrol station .

 

[MickDB1]

I always used the RHs first. Yer can still have throttle control if yrr leave left till last

 

[Crapaud]

Many thanks for the replies.
As it is only gravity pressure, I thought that just pushing the fuel pipe on would be OK. Unfortunately there is a slight leak at the T junction so I'll have to fit some small clips.

 

[theoneandonly]

you would think that a bloke with a Bentley , would have enough cash in his pocket to fill up every 100 miles !

 

[Gelandestrasse]

In addition to all the replies, there must be some design merit in having the same fuel pressure to each carb (mgh). Can't explain why, though. BMW seem to have started the '2 tap' tanks with crossover pipe from the /5 series. I tend to use one tap only unless on a fast run.

 

[Bucephalus]

For what it’s worth I seem to remember reading back in the mist of time in owners operating instructions, for the right hand to be kept under control of the throttle and brake, and to reach to the left side petrol tap to turn to reserve setting when required..