89 kx125 pv opening too far, linkage binding stuck fully open

Anyone know where e I can get an old school pro circuit PC cover with the stopper in it to prevent my PV from binding when its fully open. I'm ready to put it back together but must fix this somehow first. Pro circuit discontinued them long ago and I didnt know this was an issue when I bought the bike a year ago and trashed one .040 piston. The ring was making contact with the PV when it was closed..desperate issue. I need a cover with the stopper in it...or make one somehow..any ideas are appreciated..thanks.

Anyone know where e I can get an old school pro circuit PC cover with the stopper in it to prevent my PV from binding when its fully open. I'm ready to put it back together but must fix this somehow first. Pro circuit discontinued them long ago and I didnt know this was an issue when I bought the bike a year ago and trashed one .040 piston. The ring was making contact with the PV when it was closed..desperate issue. I need a cover with the stopper in it...or make one somehow..any ideas are appreciated..thanks.

Did you try clearancing the power valve from the piston ring?. Sorry I do not know what stopper you are referring to

I haven't taken the valves out to trim them yet they're still in he head...head is off. I only know they were hitting the ring because is reshaped the Front of the piston slightly. With the valve cover off, she I slide the PV to the open position with my finger or by working the linkage on the side of the cylinder, it binds when it gets to full open position because the long age is extending too far on the pivot pin and won't let it return. Pro circuit made an aftermarket cover with a stopper in it preventing it from extending quite so far..preventing the binding action..its clean and moves freely in all other positions but when overextended it won't retract..binds on the pin.

I meant cylinder..they're in the cylinder which is off the bike, piston out etc..putting new piston kit in..

But does the governor let it open that far while assembled in the engine? Yeah still sorry i have never seen the stopper you are referring too. Probabaly something you will have to fabricate..

Most all PVs have to be clearanced when an over bore is done to keep the piston ring from contacting them. 

I've seen those covers.  Maybe not the exact one for your bike, but it's basically a PV cover with a screw and a jamb nut.  I'm assuming the screw is adjusted in, like a stopper, to limit PV throw.

Ya right Jenkins, I just can't find one. I'll make it if I have to but pro circuit would be more reliable than what I could fashion. Lock tite is all I can say. And you cant weld on the cast alum.cover so...idk. The linkage jams after full open throttle and unless I ride a wheelie or climb a hill it stays that way. Drill a hole and jam nut on either side of the cover I guess..

Yeah, you can weld cast aluminum. Just weld a boss on there, drill and tap it,you're done.

Maybe with a tig jenkins, ive tried a few times with a gas tig and it doesn't ever take..just clumps up. In know guy that does tig..well try that I appreciate the info. Got my new piston kit today...trim the valves and fashion this cover and I'm back in business. One more fall ride I'm hoping before the snow flies to break her in..

You could try one of those drywall type anchor inserts..the metal ones with the threads that expand out like a toggle..maybe

seal it with JB. Just a suggestion dont flame me for my magyver ways. :p

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