I just bought my first quad (1986 trx350) I've been looking for this exact model for the past year and finally found one in moderate shape for $1300 Cdn. The guy I bought the quad from just had the motor rebuilt at a shop and it runs great but as I was tearing it apart for its restoration I noticed that it seems the shop used some sort of liquid gasket caulking in place of a proper head gasket. I'm just wondering if this is going to be a problem down the road or if this is a common occurance. It also seems that someone has used silicone caulking in place of a proper gasket where the front diff joins to the axle cover. Any info would be appreciated.