RM,

A couple things..... the DA flex header has a coiled steel section that is open like a spring, under the unsintered Teflon tape. Exhaust gas will find its way to the surface of the tape and will turn the tape black eventually. I had one of that style header for my 55cc except in my case the spring section actually broke .

Dont fret it. If it happens to you, get the Teflon off and grind the spring off the two ends. You can reconnect the two exposed ends using my method of ultra copper impregnated ceramic cloth. Or I'll send you a coupler. That's what I did with mine for the 55. That was four years ago and about 300 flights. It will save some weight too especially if you replace the aft steel tube with ally. Good luck

Edit- in hushed tones.....shhhhhh.....don't tell DA, they didn't listen the first time.....LOL