an someone please let me know the correct front fork oil volume required for the ยด91 Yamaha XT350. Also, any suggestions on what may be causing an Intermittent poping noise when motor in warming up. The engine has always started hard, {several kicks needed} when cold, as of late there is a popping noise which I believe may be coming from the decompression release, not sure why. Any suggestion on what may be causing this and what I can do to correct it?