We used to have 1 1/2 black pipe but found that 1” works fine. Now we use the 1 ½ as an outer shield for the 1”. My guess is that the 1” would be a little easier to handle than the 1 ¼ that you have. To uncoil a warm day helps, I think that we held the ends in place with weights while it sat in the sun for a while.
We now run the pipe along the main dock next to the breakwater with the pipe draped over the end of the dock in about 8’ of water. The length is cut so that the foot valve is about 18” up from the bottom.
On another thread I mentioned how to prime the system with a small pump down at the lake.
http://www.winnipesaukee.com/forums/...ad.php?t=15604
If you make it down on a Thursday, you can have the red dot.