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Specialized Fuse Seat Tube Troubles

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Specialized Fuse Seat Tube Troubles

Old 08-04-20, 03:46 PM
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Specialized Fuse Seat Tube Troubles

Hi there!

So I recently bought a lightly used Specialized 27.5+ Fuse 2020. It comes with a TranzX 120mm dropper post. I was considering switching to a One Up 180mm or 210mm. However I have run into a few problems!

Problem #1 : the seat tube internal diameter on the Fuse looks to be 34.9mm but the current TranzX dropper is around ~29mm so there's an "adjustable" tapered bushing or adapter to make it a tight fit (pictured). However when everything is installed I cannot make the bushing slide all the way down into the seat tube, about 2 inches sticks out. And more importantly, I cannot even remove the bushing, I can pull it up a certain amount and then it stops: I can't slide it out of the seat tube - so I cannot install a different larger dropper post. Has anyone else experience anything like this? Is my only option to cut / break it and replace it?

Problem #2 : The threads for the water bottle cage stick out into the interior of the seat tube (pictured) thereby preventing a seat post of over 210mm being inserted fully. Has anyone heard of drilling out / dremelling flat this protrusion? - in order to insert the seat post another 50mm.
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Old 08-04-20, 10:05 PM
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I see no pictures.
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Old 08-05-20, 08:50 AM
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One Up has a great online tool to figure out your max dropper post length.

The Specialized website lists the Fuse as having a 30.9 seat post diameter, so you might be stuck with the bushing. I haven't heard of anyone dremeling out the threads. You would lose use of that bosses if you went this route.

Pictures would help.
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Old 08-05-20, 06:45 PM
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newbie first post, need 9 more to be allow to post pics
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Old 08-12-20, 08:16 PM
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That sounds like a tricky problem.

For problem 1 you could try to use a screwdriver and hammer to gently tap it out of the tube (if I understand the situation correctly)

I have removed the water bottle bolts with a drill.
It only works if the frame allows you to get in front of the whole with the power drill.
Then just drill out the thread.

Good luck!
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