The only way to get pipes to not scrape if you crank your bike over is to get the pipes bent and made to fit your bike, when I converted my Commando to the Featherbed frame back in the early 80s I built everything so nothing will scrape on the bike but I was lucky as I had a local muffler shop that had a mandle bending machine and a very experienced operator, but he said it's been 20 years since he made pipes for a bike but was very keen to make mine I had the complete bike there and told him I wanted the pipe tucked right into the bottom of the frame rails, he did every bend by eye, do one bend put the pipe up to the frame then do another bend and checked again, withing 15minutes he had the first pipe bent from the exhaust port to the rear axle and my original flange in place.
Then he did the other side and after 30minutes they were finished, was a pleasure watching a true trades man working, the best thing when finished there was a new chrome plating shop just opened next door, Ken the owner of the muffler shop who made the pipes was so thrilled in making them and he charged $20 to make and the chrome plater because he only just opened he charged me $20 to chrome, once they where done it was up to me to cut them where I wanted the mufflers mounted.
That was 1982 and I am still running those pipes, but have replaced the mufflers since I have a thing for upswept pipes so the header had a upswept bend and the cocktail saker mufflers also have a upswept angle, in 41 years I have never scraped the pipes or my foot pegs as they were mounted high as well and I do push my Norton to the limits of my rubber in the twisties.
The old headers are showing their age and one header has been brazed up from small holes on the first bend from the exhaust flange but that was brazed up about near 20 years ago.
About 20 years ago Ken who made my pipes was employed at my Tec College to teach exhaust bending and he remembered making my exhaust system all them years ago, but 12 months later when he started at the College he past away from a heart attack, his family is still running the muffler shop but the mandle bender is long gone, the new bending machines aren't as good as the old machines.
So really the only way to get perfect exhaust is to get them made for your bike, but the hardest part these days is finding someone who still is old hand at doing it.
A few weeks after he made my pipes he bent a new header for my mate's 1947 AJS and in 1984 he made a set of stainless steel headers for my 1981 Triumph Thunderbird.
100 miles from my place there is a tradesman who make x-pipes (Meerkat Exhausts) for our modern Triumphs he also make custom pipes a one man operation and he sells world wide, he made my x-pipe and opened up my stock mufflers for my 2016 Thruxton, so there are still great pipe makers out there, you just got to find them.
A pic with these made headers after 41 years on the Norton.
[ATTACH=full]111520[/ATTACH]