Mend > Motorcycles

How can i fix power loss in my Gilera DNA 125cc?

Ive had my Gilera DNA for two months now and it was running well until a few weeks ago, when the power would just cut out. I would be say doing 60mph nearer the top end of the scooters performance and the power/speed would drop of too about 30mph yet my throttle hand would be twisted up at the 60mph it would do this for maybe 20-30 seconds maybe a couple of times a journey. It also kind of back fire's either before or after the power drops making a kinda popping noise.

I recently changed the air filter, the fuel filter, the oil filter, done an oil change too and i've put fuel cleaning fluid into the petrol tank. The scooter still looses power though but only goes down to about 45 now not any lower and it only happens when i go over 60 mph ish, if i keep to 50 it wont lose power at all during a journey.

I changed the spark plug recently too and i've read other people having the same problem and people suggested it could be a faulty HT lead?

Any suggestions?, thankyou

David
July 2010

Gilera Gilera DNA 125cc Vehicles, Motorcycles Power Weeks Ago

i had the same problem on my dna 50, what i did was i took the case of the air filter and stretched the air filter sponge then i sat it back into place but make sure it is stretched when put back into place. the cause of the power loss is the air intake is sucking the airfilter throught he tube and therefore blocking it making it loose power, hope this helped, if you get any more problems email me on rossfenwick[at]live.co.uk :)

Ross Fenwick
November 2010

Thx i will have to try that and see if it works

David
July 2010

mmmmmmmm sounds like either the head gasket blowing on it or one of the valves leaking on the seat.i would take the head off and lap the valves in and clean the head up niceley or get it skimmed and put a new gasket on it.

adam bike doctor
July 2010