ds 450 won't start

[xcrcr]

While riding over the weekend my Ds450 died ran perfect up till then I didn't hear any thing breaking inside it just shut down. I pulled the injector and its squirting gas like it should I checked the timing I pulled the plugs and it has spark but the insert was broke in the cap on the inside plug not sure it might have broke when being pulled off but it still made the plug spark and the motor won't fire. I held my finger over the spark plug hole and it barely had any compression while cranking it over but I'm not sure how much it should have with the compression release and shouldn't the compression release disengage once the starter is turning the engine over. Any info you guys could give me will be appreciated

[hcomras]

Rings? No compression. Sounds like it maybe...dunno for sure tho

[beamer]

get a compression tester and test the compression with about 2 tablespoons of oil in the engine, if still no success than you might need to rebuild. Also your valves could be off so it may be as simple as a valve adjustment or as complex as a rebuild....If you're not mecanically inclined and don't know much about engines and stuff, I'd say top take it to your local shop to get them to see whats wrong with it.

[xcrcr]

I tore it down last night and it ended up being a problem with one of my valves Thanks

[WIZ49]

Thanks for the closure...there's a lot of these threads that end with no solution.

[dickanSWE]

It seems like i have the same problem with my 450 '09. I was out riding it and suddenly it wouldn't start.
Got fuel, got spark steel no light up.
Checked the comp and it was pretty bad.
So what exactly was the problem with the valve???