I'm new to 4 wheelers and I have question. I bought my kids each a used 2001 - 2003 Polaris 90cc 4 wheelers (One is a sportsman the other a scrambler). I just want to make sure I keep them running right and take good care of them so they will last. My kids are not the type to break or tear things up so they will not abuse them, but is there anything recommended I should do on a regular basis (Daily, monthly, yearly) to keep these machines running right. Whatever it is I will do. I know the ones I bought are old but old doesn't mean trash if its fixed up and taken care of....right? What should I look out for as far as where and tear goes? What should I replace regular, weather its bad or not, just to be safe? What should I look out for that goes bad on a regular basis so I can buy a couple to have laying around in the event it breaks / wont start?
Welcome to the forums.
Keep the air filter clean and make sure to run ethanol free gas.
It might not hurt to do clutch maint (clean up and check rollers for flat spots)to make sure all is well. I'd do that after 15-20 hours of riding.
Unless the machine requires premium (non ethanol gas) their is no need for it. Very few machines of that size require premium fuel and its just a waste anyway. I have been running ethanol fuel for years with no issue at all. I usually don't use additives but this year i started adding a stabilizer to the fuel can that operates my little quad and power tools. The biggest problem with the ethanol fuel is people add water eliminator and then it will react and gel in the tank causing issues. I used to let the smaller quads and tools sit for 6 months out of the year go out and fired right up in the summer with no issue. I ride with a large group and no one runs prem except for a few of the high end/performance machines.
Now back to your question. run a good synth atv compatible oil this is not a area to be cheap in. Any area that has some movement in the suspension and does not have a grease fitting add one. If they are going to sit for any amount of time like a few weeks or more pop a battery maintainer on over night to keep the battery's topped up.