YZ250 Power Valve Question

[BigYZ]

Ok, I need a little help here folks. I actually need help in identifying a part and it's function.

Upon opening the cover of my power valve, a small half circle shaped piece of metal fell out. This is described in the manual as a "Plate" It's a half circle with a tab in the middle that a screw goes into.

All I need to know is, what this thing is and what it's function is.

Thanks in advance.

 

[bclapham]

what year are we talking about? also, there are blown up parts diagrams at www.yamahaoftroy.com maybe you can look it up there and get back to us!:)

 

[BigYZ]

Originally posted by bclapham
what year are we talking about? also, there are blown up parts diagrams at www.yamahaoftroy.com maybe you can look it up there and get back to us!:)

I figured it out, it's a thrust plate. It's function is what I still don't know.

The bike is an 84 btw.

 

[mackay]

If its off the right side of the engine (kick starter side) then its a retainer plate. The power valve is held in place by a retainer plate on the left side and on the right side, since this is where the actuator arm connects a plate wouldnt work so a clip like you describe is used. There should be a screw somewhere in there too that retains the clip. I wouldnt operate the engine without that clip in place, I'm not sure but my concern would be the power valve comming into contact with the piston, which we all know is a BAD thing. Make sure you find that screw too as pieces of metal and the innards of your engine dont mix too well...good luck

 

[BigYZ]

Thanks for your relies, I figured it all out. I actuall just fabricated a new piece out of metal and drilled it and it works like a charm.

I will ride this weekend!!!