YZ 465 not easy to start

[johnny b]

Just got this o'l yz,81',seems to be in good shape for the age. Has good compession,cleaned the carb,flushed tank ,freash fuel,etc. Runs pretty good,but a terror to start,especially when warm.Iv'e worked on bikes on and off for years{59 years old} but I'm lost on this one. Any help,questions,comments,etc. would be greatly apreciated. Thanks,,Johnny B

[lms6201]

reeds hanging open , esp if fibre ones , get a set of std steel ones , crank seals  does the exhaust smell of gear oil /  check the timing , mabey too far advanced the 490 is 2mm btdc  465 at a guess is the same , weak mag coil wil do it  , weak ignition coil ,  some of the above can be heat agrivated , fibre reeds may warp when hot (my theory only ) , mag coil insulation has (on one of mine )broken down when hot , but when cold was fine , float level if a bit low can make hot starts difficult , if worn greatly in the cylinder the extra clearance when hot can afect 

[Rossvickicampbell]

maybe move the thread down to the Yamaha section and you may get more info from the guys there?

cheers

Rossco