Sparks

Hi AIRHEAD Just to let you know , after examining cylinder and liner , some idiot has rebored liner so much off centre towards exhaust port that the piston contacted the power valve . So I will be using a different barrel for rebuild. Thanks for your input.

Hello everyone i have joined your great forum today after browsing posts this weekend.i have dt125r which I am repairing for my 17 year old son.Sam! Having problem with powervalve positioning and type. My barrell and head is type BN Have fitted barrell piston and head from spare engine . New gaskets used.piston and bore is+1.5mm. My problem is the powervalve when set in locked position has rubbed on side of piston and caused rings to Jam in grooves. Now I need a new piston Is this because the barrel has been bored out +1.5mm? ! Does anyone know if there are different powervalve sizes . I fitted powervalve from barrell and head code MB which would not fit in unless modifying. Have tried 180' but it in open position .have got 2 types now , one has diamond shape on end (4 position ) other has 2 flats (2 positions ) both have location pin on pulley wheel but in different positions. Any advice on set up position please ????????Would like power valve open.

Hello everyone i have joined your great forum today after browsing posts this weekend.i have dt125r which I am repairing for my 17 year old son.Sam! Having problem with powervalve positioning and type. My barrell and head is type BN Have fitted barrell piston and head from spare engine . New gaskets used.piston and bore is+1.5mm. My problem is the powervalve when set in locked position has rubbed on side of piston and caused rings to Jam in grooves. Now I need a new piston ! Does anyone know if there are different powervalve sizes . I fitted powervalve from barrell and head code MB which would not fit in unless modifying. Have tried 180' but it in open position .have got 2 types now , one has diamond shape on end (4 position ) other has 2 flats (2 positions ) both have location pin on pulley wheel but in different positions. Any advice on set up position please ????????Would like power valve open.