Are you talking about starting it now a days (in winters) or generally? If you are talking about winters then do not worry, cold temperatures thicken the engine oil and it is hard for it to pump throughout the engine when thick. I read in Honda CD 100's owner's manual to keep ignition in the off position and kick-start the engine 2 - 3 times to circulate "cold" engine oil in winters, then turn on ignition switch and attempt engine start. It helps in starting engine easily in winters.
If it does not work for you, try making the mixture a little richer.
Hope it helps.