Fuel reserve switch

[Duane.Hoffeldt]

Hi guys, I have a silly question and was wondering if anyone could enlighten me. I have a 93 and according to my Haynes manual, when the fuel in the tank reaches a reserve level, the power supply to one coil is cut setting up a misfire on two plugs - this basically informs the rider that the fuel level is low. Switching the fuel switch into the reserve  position is then supposed to restore the power supply to the coil and off yer go again (well at least until the fuel runs out completely).
However this does not seem to be the way my bike behaves, when the fuel gets to the reserve level I dont experience a sudden loss of power and a rythmical misfire (as if a coil has suddenly gone dead) rather, my bike exhibits typical fuel starvation symptoms, starting off with an occasional surging, lumpy idle, gradual loss of power and eventually the idle speed rises up until the bike dies. Switching the fuel switch to reserve does not immediately restore the power (as if a coil had been turned on) rather it takes a short while for the loss of power and lumpiness to smooth out again and full power to be restored.
My bike definately does not have a solenoid fuel cutoff valve or vacuum operated tap that is wired into the fuel reserve switch, so i was wondering if the switch is perhaps wired into the fuel pump circuit - ie power is cut to the fuel pump when going onto reserve, setting up a true fuel starvation scenario. Is my Haynes manual wrong or is my assumption wrong?

[RichBaker]

Haynes is wrong. The fuel pump relay shuts off the fuel pump when the low fuel light comes on..... as you guessed.

[ELIMINATOR]

That's my understanding as well.

Further question though. I wouldn't say that the fuel pump is switched off directly that the fuel light comes on. I have driven a few miles before hitting the reserve switch.

I've never had the nerve, not to switch at all though. I can just imagine the bike cutting out when I was about to overtake!

[Pat Conlon]

...... I can just imagine the bike cutting out when I was about to overtake!

...or in the apex of a 70mph sweeper as you are rolling on the throttle to power out... I really dislike that fucking thing on my '92

I don't get it. We have a fuel gauge, idiot light and a odometer and still we need this...? 

[Harvy]

...... I can just imagine the bike cutting out when I was about to overtake!

...or in the apex of a 70mph sweeper as you are rolling on the throttle to power out... I really dislike that fucking thing on my '92

I don't get it. We have a fuel gauge, idiot light and a odometer and still we need this...? 

That's why my switch stays on the RES setting all the time Pat. And with a key that comes out of the Ignition switch while the bike is running, I can check the contents of the tank on the move!


Harvy


Harvy