Cam Timing Issues

Sky Rider

Hey guys.
I'm currently in the middle of rebuilding my engine and ran into an issue. While installing the cams everything goes well until the tensioner is installed. Once tension is applied the crank turns about 20 degrees CCW. I'm using cams with Ape adjustable sprockets. I've tried re installing several times and always get the same result.
The camchain slack needs to all be towards the rear when you put the cams in, the front run of chain needs to be snug. When the tensioner is installed, the crank and cams should stay put.
I watched the Tombo Racing vidoes a few times before i attempted mine. if you have stiff valve springs, i found that i had to slowly tighten the cam tensioner down as i tightened the cam guides down to keep the cam chain slipping over the sprockets. is the cam timing right? my cam sprockets arent installed per APE instructions so you need to make sure the two lobes on #1 are pointing towards each other (if i remember, please correct me if i am wrong) when at TDC just to get its installed and then check/adjust the cams to the spec'd settings. took me many tries to get it right.
When I installed it I installed the exhaust first and made sure it had the tension on the back. I'll try the tightening down while I tension and see how that works.