Aprilia 150 leonardo, flat battery and not charging, only 11.5 volt when running. Is it the rectifier and where is it fitted to bike? Thanks

Its better u take it to a motorcycle service, they can check the voltage that the scooter produces to charge the battery, maybe its the regulator or the magnetic field.

I am not familiar with the Mojito's qwarks. Sometimes the charging systems are underpowered and can't keep the batteries charged on some scooters. Check with Aprilia to see if there is a recall or service bulletin on the bike. If the bike started and ran fine when it was new, and you have the factory sized battery in the bike, then the problem is not with the battery size. If the battery is more than 2 years old, replace it. It may show as good on a volt meter, but it may not have sufficient amps to crank the engine, or be able to hold the charge. The dealer should also check the charging system to make sure it is charging at least 12.8V at idle, and well over 13V (volts) when the engine is revved up. Most scooters charge at 13.5V-14.7V when revved up. It shouldn't exceed 15V. An Aprilia dealer should have the factory specifications for the charging system and can test this in just 5 minutes. If you are having a charging issue, then it is most likely your voltage regulator/rectifier or your stator. The stator is what produces the electricity when the engine is running, the regulator is what smooths the power out and sends it to your battery at the proper voltage. Regulators fail more frequently than stators and are cheaper to repair. Other possible problems are the starter relay or the starter itself may be worn out and drawing too much power. Again, if the bike started fine when it was new, and you have the factory sized battery, then don't change the battery size. You may only be treating the symptom and not the problem. And applying more power can simply cause more damage. If the problem is that you just have to run the starter for a long time before it starts, and you just run the battery down, then it may have nothing to do with your starting system at all. It may be a low compression issue, dirty carb/fuel injection problem, old spark plug, etc. Hope this helps. www.solanocycle.com

I think you have a charging issue or u/s battery.Put a test meter across the battery terminals and run the bike.Raise the revs and Check that the voltage is rising above 12v DC .If so do the same test with lights on if OK I suggest you replace your battery.

put it on a charger and then start it.  pump the gas to prime it.  You'll need to replace the battery because it's shot.  I have a Aprilla 250 and love it.  

stopped for lunch back on bike it started fine. About 20km later I heard the engine revs on my speakers running autocom of the bike the speedometer started going mad jumping from 30km/h to 220km/m, all over the place. The last time this happened was in France and the bike did not start again, battery was flat, bike shipped back to Ireland. Back in Ireland the dealer kept it for few days, battery was fine just needed to be charged, could find no other problem with the bike. While this time I rode straight to the dealer, about 20km away. When I stopped the bike was dead, no power. They did a test and said the regulator is faulty. Was waiting for new one from Aprilia but it did not arrive today so they took one from a new bike. The bike is charging when reved but does not want to charge at idle so they need to go fishing for the fault. It now also seem my clocks are broken as a result of al of this. ,Check to make sure that all of the chassis grounds are free of corrosion and properly connected. I have never had an issue with charging at temperatures ranging from below zero into the mid/high thirties (Celcius). Even at low speed you will be turning 3000-4000 RPM which should have the charging voltage between 14-14.5 V. Put a multi meter on it and see what voltages you are getting at different RPM's,,,