Can anyone help????? 87 ZILLA

[michael_marone]

I have a 87 LT 500R with new reeds and fresh 106 octane and a 30:1 ratio with Belray synthetic 2 stroke oil. I was riding it, it was running great for about an hour, when all of the sudden it just started breaking up and died. I checked the plug it was clean I checked spark it was good I checked compression it was about 130 psi. Does anyone have any idea what is going on?

[SHOWTIME]

moved ya to the zilla section...the
zilla pros will help ya!

[FPMXer]

Welcome to E2S. It sounds like your rings might have worn out a little. 130psi is low on the big bore. I had a 145psi and due to a leaky base gasket it ran like shit. I run the same premix oil at 40:1. Post a pic of the plug.

[fulltiltrider]

yeah 130 is pretty weak. Time for a new top end

[Musclequads]

Originally Posted by michael_marone

I have a 87 LT 500R with new reeds and fresh 106 octane and a 30:1 ratio with Belray synthetic 2 stroke oil. I was riding it, it was running great for about an hour, when all of the sudden it just started breaking up and died. I checked the plug it was clean I checked spark it was good I checked compression it was about 130 psi. Does anyone have any idea what is going on?

Need more info, as far as mods, etc.
To give a really good Guestimate!!

[wicked251]

You might have broke a ring. Better pull that top end apart before something real bad happens. I think I had around 175 psi on my top end, but I could be wrong(its been a few months since it was checked). I dont think rings will cause the combustion to break up, as the engine should run with less power. I had my motor break up bad last spring while racing a predaturd, come to find out my fuel filter was partially clogged and couldnt flow enough for extended WOT. Something else to check. Good luck.