losing power

hi im new to the forum.. i gots a question.. my cavy is loosing power.. i can notice it.. just a while back it would spin up asphault.. now it spins less and when i go to shift it requires more gas and accelerates slower.. what should i do.. thank you

what year?
Have you changed your tires and rims lately?
If you have changed them most likely you have just added not only weight but more rubber contacting the pavement which in turn will also limit your spinouts with a stock set up.