Derbi senda extrem 50cc sm Can anyone help ,lights keep going off and battery keeps dischargeing even with new battery ,

SOURCE: unable to get first gear.

I understand that Honda's have this problem when they warm up. Try slowing down a bit more before shifting into first.Also, ensure you are kicking it all the way down past neutral. If the problem occurs from a standstill, try rocking the bike back and forth in neutral as that sometimes does the trick.

SOURCE: 50cc 1999 derbi senda

Hi
Decarbonise the exhaust system.

Regards
Phillip

SOURCE: spark plug locatio on derbi senda 50cc

The spark plug is located at the top of the engine under the tank. It is the rubber plug cap (usually black) located in the middle of the cylinder head that you must pull off to get at the spark plug

Ride safe
Bike-Doc
Please mark this as very helpful (if it has been!!)

SOURCE: i want to have more horsepower

Hey. Replacing the stock cam with a performance camshaft will help. To gain more horsepower you should also make the airflow to the engine better. Replacing the stock sylinder with a big bore 150cc kit will sure make the engine more willing. The engine on a 08 Derbi senda baja model, is the same engine that you will find on a Yamaha TTR 125. So that is what you should search for. Hope it helps:)

SOURCE: my derbi senda 50 pro

first have the head trued at a machine shop then get new head bolts, clean mating surfaces spotless with a non residue cleaner such as brake clean DO NOT TOUCH ANY SURFACE AS YOUR FINGERS LEAVE DEPOSITS that includes the gasket, torque to manufacturer spec with lightly oiled bolts,