2001 yz 250 power valve questions

[trev]

hey i am new to the fourm and could not find many topics ( searching).. I blew up my 01 yz 250 about a month ago and sent the cylender off to get re plated and I can't find a service manuel anywhere. My problem is that i don't know how much pre load to put on the power valve spring, and I could also use any torque specs for the cylender head bolts . Any help would be greatly appriciated because the dealer isn't too willing to help me.

 

[jimmy 420]

i hav a 97 rm125 and i also am not sure about the preload on the spring i looked in the manual and it said once u feel tension on the spring go one complete turn it doesnt seem like enough to me but i am goin to try if it keeps stayin open i might go a bit more i dont think u should go to much tho it would put more pressure on the linkage for the power valve

if u r not sure i wold say to call a yamaha dealer they should no what to set it at

 

[jp2396]

You can buy manuals online from Yamaha.
http://www.yamahapubs.com/html/index.html