I am going to replace the dropper seat post on my wifes Specialized Rumour mountain bike. She wants me to fit a lighter carbon post as she does not use the dropper post. My question is I have a 400mm long post. I need to cut about 70mm off the bottom to allow it to fit into her small frame. Will this cause any issues? Seems like a good idea to me but I've broken plenty of things before.
Yes, you can cut the carbon post. it should be done with a blade designed for carbon. It can then be finished with sand paper or emery cloth.( finer grades ). I would like to note that if she adjusts the seat often ( for different riding styles ). I do not recommend a carbon seatpost. Also the weight saving is not worth it, the are not very rugged and often way more expensive and not much lighter than a quality alloy post. They look pretty in the box thats about it. there are many other ways to "Shave weight" than a carbon seat post
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