Sounds like a TVI job to me (I had the same problem) You will need to get a new piston so you can set the cylinder deck height correctly without your piston being way below deck.

 

I did the same thing to my DS after adjusting the valves. Instead of lining up the mark on the flywheel I found "true TDC" and thats how I ended up with bent valves. When you line up the marks to Bombardiers TDC specs it's actually like 12 degrees before TDC or something on that order so the valve has enough room for piston clearance. I'm not exactly sure on that but you might wanna re do your timing by lining up the marks....

 

hmmm mines kinda contradicting with pushins, i also bent my valves while adjusting them, but wen i put the cylinder back on i had it set on exactly TDC, then i put my head back on, and set the cams the best i could, then i'd triple check until it was set as close as possible, i noticed mine was off by about 1/2 tooth, but i just rotated the crank by hand a few times and it hand to make sure it was set rite

 

ya the antifreeze was on the floor rite under the radiator and it doesnt do it anymore so i think the radiator cap may have been loose. about my piston height in the cylinder i would have to ask my builder because i wasnt there at that stage. i was really floored when i called gary and he told me that there is no way this could happen when i was telling him it is happening. well ive had it running several times. I'm going to run my msd box turned all the way down to be safe. With these storys about tvi I'm not even sure what my compression ratio really is.

 

took it out for a ride today, ran really good, I didn't even open it up at all, probably about 3/4 throttle and that was it. this thing rips, the thumb throttle pull on these duals is insane, i'm gonna have to do something, maybe fuel injection or a lectron is calling my name and then I would just sell the manifold, carbs and filter, but I will wait and see. I'm gonna take pics as soon as I can.

 

glad it worked for you, seems a few people have bad feelings on this kit but i have to say it works good for me.

 

ds650king, whats the latest and greatest with your 720?