I have a 95 kodiak 400 4x4. took it yesterday for a ride since it was warmer out. as of right now i have 10w40 spectra 4 in it. the quad seemed to be running great until it warmed up. the valve train started to get noisey and i also noticed that my fuel filter was not staying full.

when i took it out over the weekend when it was colder the motor did not have a noisey valve train. here in michigan it is still cold at night but durring the day it is getting up to high 30s low 40s do you think the oil i have in it is too thin now and need to go to a heavier oil? any input on this would be greatly appricated as i am new the the atv seen