aaprilia rs 125

[aprilia rs 125 2001]

Hi was running my aprilia rs 125 2001. Last week on my way home from work. It ran fine went to start it agian after letting it cool down. And now it wont start. Just struggles on low revs. Ie just keeps cutting out) and it wont start on the starter

[stirlinggaz]

hi,
i'll give you usual reply, for the rs125.
check battery voltage, NOT using the lcd but with a multi-meter. voltage, should be over 12.5v when off & with the engine running around 13.5v. (charging circuit doeS not kick in till 5000rpm)
12v or less & the rs refuses to start & can be quite tricky to bump, try bumping in 2nd gear, down a hill.
If its less than 12v, you might need to buy a new battery, however i have successfully re-charged batteries from as low as 5v, but it takes a specific type of battery charger to do this, more expensive than a new battery.
NEW spark plug : plug should be treated as a consumable on this bike. carry a spare BR9 under your pillion seat.
compression test : any less than 110psi & its time to get that head off & at least give it new rings.
fresh fuel : try a wee drop down the spark plug hole before hitting the Starter.
resist any temptation to start f*cking about with the carb, the dellorto 28mm carb on this bike can be very sensitive to even the smallest changes to the air/mixture screw (small screw on side of carb that can be adjusted by a flat bladed screwdriver) & throttle stop screw (black plastic knob on side of carb body)
post results,
cheers,
GAZ