Bicycle Rod Holder

Anyone out there have success with a bicycle rod holder constructed out of pvc?  I've seen multiple rigs for a rear upright rig with rods vertical, however with longer rods, esp fly/pinning rods even broken down will tangle with trees if riding on trails.  Looking to make a horizontal rod holder under seat mount and curious if anyone out there has made one and would be willing to throw out some pointers.  Would be ideal riding along the Yough.
 
Thanks!

I have strapped mine on, horizontally along the top frame bar and out the back.  I made a pvc tube holder to protect it (not intentionally for biking, but worked just fine).  If you don't, your tires will kick up debris and hit your rod.  Buy the 8' piece (size depends on what you are putting in) if you have a vehicle that can safely transport, and cut to size needed (or take saw to parking lot and cut there, with box to collect debris).  Put a screw on inspection cap on one end and a dead end on the other.  Similar to what the plumbers have strapped to their roofs which are also good for putting multiple rods in as well.  Good for protecting your rod when packing in your car for vacation, and stuffing things in, which is why I really made mine.  Attach to your bike with some reusable wire ties, easier to take whole holder off to get out.

3/4" might be a bit small.  I only use the stuff for making crap occasionally, so don't really know the sizes until I am at the store...  I do think the 3/4" is what I used to make a frame for my boat cover.  Break your rod down and put together, then find your widest part.  I'd go a little wider, since your eyelets will end up interfering with each other inside, and you don't want to jam your rod getting in and out and end up bending or breaking something.  I'm not sure what size that I used, I think 1 1/2"?  I used it on my kayak too for additional rod holders.  I cut a slot in to accept the reels.  I had one that worked with my fly rod, but put a velcro strap around the upper portion of the slot.
 
If you are going to let your reel hang out, I'd get some sort of reel protector.  My one reel came with one.  Made of neoprene and velcros to shut, around your reel and reel seat.  You could probably make something from craft foam for $1-$2.
 
I'd also check ebay for a flyrod bag/case.  You might be able to just find one of those used and as cheap as piecing all of this together?