Someone made a comment awhile back about running a rag soaked in cable lube through the conduit before running the cable. I use half a plastic bag instead of a rag, but the lube pre-pull makes a big difference if you've never tried it before.
Had a crew pulling some buried cable in 300 feet of 1-1/2" grey PVC with three 90s and four 45s. They couldn't push a fish tape down it, so had them try a small 2 HP Walmart shop vac that I use for general cleanup instead of my 6 HP shop vac for that. Good tip - use half of a plastic Walmart bag tied to a pull string and the small vac pulls it just fine (a whole bag tends to clog up).
They ran the pull sting and there was a too much friction with the string getting pulled around the turns. So I had then pull half a plastic bag covered with lube in both directions. They had the whole pull job done in ten minutes later.