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ABCD ABCD
ABCD ABCD • Apr 26, 2012

Old Scooters Q

Hi, anyone seen/remember?
Every old scooters had a control switch which was normal mode and reserve mode.
When the fuel inside a tank gets verymuch exhausted or decreased. We need to switch to reserve control in the vehicle. Only then, the vehicle would start or can be used. I think this is still there in TVS XL. Anyone know how it works?
zaveri
zaveri • Apr 27, 2012
As a matter of fact, this control is present on most of the 2-wheelers, that are in the market today.

there are three modes in such switches, "off" , "on" and "reserve".

this switch seems to be nothing, but a valve, which regulates, the flow of fuel from the fuel tank to the carburettor.

now when the valve is thrown in the "reserve" mode, i think the cross-sectional area of the flow pipe is reduced considerably, when compared to the cross-sectional area in the "on" mode, so that the flow rate of fuel is reduced considerably and even the little amount of fuel that is present, will be used rationally , till the tank is completely empty.

now it is the drivers's job, that as soon as he flicks the control in reserve mode, he uses it to ride to the nearest petrol station to fill up
mreccentric
Hi, anyone seen/remember?
Every old scooters had a control switch which was normal mode and reserve mode.
When the fuel inside a tank gets verymuch exhausted or decreased. We need to switch to reserve control in the vehicle. Only then, the vehicle would start or can be used. I think this is still there in TVS XL. Anyone know how it works?
It is still there in all the latest bikes like Hero Honda Splendor, Honda CB Twister, Bajaj Pulsar too... Who told it is not there?
ABCD ABCD
ABCD ABCD • Apr 28, 2012
zaveri
now when the valve is thrown in the "reserve" mode, i think the cross-sectional area of the flow pipe is reduced considerably, when compared to the cross-sectional area in the "on" mode, so that the flow rate of fuel is reduced considerably and even the little amount of fuel that is present, will be used rationally , till the tank is completely empty.

now it is the drivers's job, that as soon as he flicks the control in reserve mode, he uses it to ride to the nearest petrol station to fill up
Cross sectional area of flow pipe - So you mean volume of fuel being in flow reduces. You Know, if the driver does not switch to reserve control (when fuel amount in tank is low), then the vehicle stops running. Acc to me, the amount of fuel flow wont make any difference. I wanted to know why the vehicle will not be able to run as mentioned above.

In that case, the scooter should be able to run even in ON control (instead of Reserve control). Reserve control is not needed if it works so.
lovejeet
lovejeet • Apr 29, 2012
actually the need of reserve kind of thing is to let the user know that the fuel is going to end soon. so how it works?? i guess, there is a certain level/point for fuel in the fuel pipe below which normal mode, that is "ON" mode doesn't work, and the vehicle stops if its in the normal mode and the user has to switch to the reserve mode, then only the fuel below that level point can be used. Another point to keep in consideration is that even if the fuel is above reserve point, the reserve switch will work along with the normal "on" switch, and below that point only reserve point works. so better don't drive in reserve when it's not actually needed.
ABCD ABCD
ABCD ABCD • May 4, 2012
okay, but what mechanism do you think they use? cos, i see the valve is in unmovable location.

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