Powervalves Stuck in jug, any ideas?

I have a 2000 RM 125 that I am rebuilding, I pulled the jug off to slit the cases and I noticed that the powervalves are seized in the head. I have soaked the jug in wd40 and a diesel mix for days, wont budge. I have carefully tried to break them loose without doing any damage with no success. I have also put the jug in an oven at multiple temps multiple times and I still cant break them loose. I am open to any ideas and I hope someone else has experience in fixing this issue. I do not want to buy a new jug or a big bore kit because if I am going to put $1000 into something it will be towards a new bike. Any help would be much appreciated.

The best thing to use for frozen parts is PB blaster penatrating lube... keep soaking it in PB blaster for about a week and it should come loose. I've seen this stuff free up old tractor motors that siezed from sitting..

X2 for PB. It got 2 bearings out of my cases that the shop said needed to be cut out. Just let em soak.

I would also consider using carb cleaner, it's desgned to work against petro based carbon deposits and that's most likely what's jamming your power valve.

I would also consider using carb cleaner, it's desgned to work against petro based carbon deposits and that's most likely what's jamming your power valve.

I have seen this in an older KX250, soaking it with PB and/or I think Yamaha makes an excellent soaking chemical can't remember the name but it works great.

Let me ask my friend at the Yamaha shop and see what it was called and if it is still available.

thanks for the replies, I will soak it in PB blaster for a few days and see how that works. I am probably going to buy a new bike anyway, I would like to have 2 bikes this 125 and an rmz250.

I would recommend running race fuel in the RMZ250, it is more but the life of the bike will be extended.

The premium pump fuel has ethanol and other oxygenated additives that lend to short engine life.. -- for race bikes --

I have been using it for over 20 years and there is a huge difference when you tear down a motor that ran premium compared to VP or other leaded racing fuels..

I agree, I have always ran turbo blue in my bikes unless I was in a pinch or oddball situation. The bike responds to the fuel so much better. With this bike being a 125 the throttle is pinned all the time so the cleaner the burn the faster the bike.

The type of fuel to use holds as much passion as the "correct" 2 stroke premix ratio. I can say that when I had my z450 I did a lot of resarch on that subject and it pretty much boiled down to how modified your bike is. Most riders in the four stroke forums agree that if your bike is stock then anything beyond pump premium is a waste.

This is the 2 stroke forum, post a question in the z250 forum about "what fuel to use in a stock z250" and see what they say. Or just seach the forum for what gas to use in a z250.

The type of fuel to use holds as much passion as the "correct" 2 stroke premix ratio. I can say that when I had my z450 I did a lot of resarch on that subject and it pretty much boiled down to how modified your bike is. Most riders in the four stroke forums agree that if your bike is stock then anything beyond pump premium is a waste.

This is the 2 stroke forum, post a question in the z250 forum about "what fuel to use in a stock z250" and see what they say. Or just seach the forum for what gas to use in a z250.

The fact is the leaded fuel runs cooler and does not contain the oxygenated/ethanol additives that destroyed HIGH-RPM's 4t & 2t bikes period.

It does extend engine life, it is not a waste, run some 87 in there and see how long it is before a 4t bike gernades...

I run 85% ethanol in my high comp builds, ethanol doesn't destroy anything when properly stored. Stuff is so clean I would argue that as long as you don't let it take on too much moisture it will extend your engine life. Has a nice cooling effect too.

I'm with Zig, for your average bike anything past pump premium is a total waste.

Well I have yet to free these powervalves, I did buy some more PB Blaster to see if that will do the trick but I am highly doubting it. I want to put this bike back together for a second bike because it has only seen 1 race season, it looks like a new bike. Thats how we maintain our equipment though. I have a wanted ad on here for a jug or even a 2001+ motor. Thanks for all the input from everyone.

I wonder if a restoration shop could dip it in a carb cleaner/soaker and get them loose. I bet it would work and shouldn't cost too much.

I got to see a photo of this stubborn bumble bee! You are tell us that they will not move at all? Did the piston hit the valves?

LOL, I was thinking pic too but I didn't want to be the first to ask.

I am posting some pics of the powervalves here in a couple of minutes

Here are a few pics of the stuck powervalves. As you can see they are seized in the chamber, I have tried so many different things to try and break them free and they havent budged at all

powervalve2.jpg

powervalve1.jpg

here are a few pics of the bike, its super clean and has only one hard race season on it. This is why I want to put it back together and ride it as a backup.

CIMG2339.jpg

CIMG2340.jpg

I think at this point I would use some B-12 carb cleaner. The yellow tint could be heated fuel varnish that is just like super glue when it sticks. Thats all I got, your bike is clean and this made the most sense to me.

I agree, soak it in carb cleaner..

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