Steve Bethany Poston

I just got an old YFM200DX Moto 4 and upon checking the oil in the rear differential I took out I assume the fill plug and it fished out old nasty oil. I plan on flushing the oil and replacing but was wanting to make sure if you drain bottom plug and just fill up to the check plug. Only thing I can think of someone filled it up by the breather on top? Plan on unhooking the hose and blowing it out tomorrow. I also do not have a service manual yet. Also right now the diff vent hose just goes up under the tank to nothing. Does it plug into back hole in the air box? Thanks 

Great site 

New member here, working on a newly acquired moto 4 YFM200DX. My son and I are working on it together. I have several ? And working on my 10 posts for a download on a service manual. Thanks and seems like a great forum