whats up guys thanks for all the responses regerding mileage but my concern today is i use the suzuki oil now and id like to switch to synthetic but a person that works at a bike shop told me that the oem oil is better because synthetic causes seals to fail basicly siad that synthetic oil makes ur bike leak so if u run synthetic or have better knolage of the oil please let me know also how long have u been runnnin synthetic thanks mean while keep it at least on 1 wheel