Cannondale Synapse seat post will not insert

bigcalves

I am putting together a 2016 Cannodale Synapse as an extra bike, it comes stock with Di2, and the Cannondale seat post is set up to hold the battery internally. I have built 4 different bikes with Di2, all run internally and no issues. I cannot get the seat post to slide down into the frame. It will go down a little and then get stopped there. I have put some pressure on it and it really does not go further. When I backed it out I noticed markings on the Di2 cable, it would appear they are getting pinched in there. I took the whole seat bolt assemble out (the bolt and both wedges), plus I also took out the water bottle bolts, to ensure the post had as clean a run as possible, just to get it in there. It helped a little, but the post did not slide in there well. I gave it more pressure, I got the post fully in, but it did not feel right. I pulled it back out to try it with the bolt and wedges and when it came back up the Di2 wire was shredded. It still works, but was rather concerning. Before anyone ask, yes I used carbon paste on the post and on the seat bolt parts.

My next step is to go see a dealer and get their help, but I wanted to know if anyone had seen this issue, or had any advice. Thanks.

bbrap

Have you tried taking the BB out, connecting the wire to the battery and then feeding the post in whilst keeping a little tension to the battery wire. That way it should not be able to snag as the wire will effectively be straight down during post installation.