I need opinions from more sophisticated bike-savvy techs on here…I am involved in a dispute with a buyer over a purchase. Not here to air dirty laundry. I want to learn and figure out a solution.
Frameset was sold with a full-length, uncut steerer tube. The aluminum insert was glued into place. Buyer’s LBS claims the star nut was also glued into place, and that because the star nut was glued into place, the steerer cannot be cut and he is “stuck” with a full-length steerer tube which he does not want. Is this true? Any solutions to work around this and allow him to cut steerer to the length he now desires?
Depends on whether it’s an actual star nut (which is pounded in as Jim says, so it can only advance further one way and not ‘retreat’), or some other kind of anchor ~ a few of which are glued in (vs some sort of expander wedge type which is typically less secure, but removeable/adjustable). The 3T fork that came w/ my old Cervelo was the glue-in type, so while I don’t think it was that popular compared to some of the other options, they definitely came w/ some builds.
The key question then is how much the new owner would like to shorten it. If the steerer is truly “full length” from the factory, that’s usually tall enough for at least a 61cm frame (typically there’s only 1 fork across all sizes for a given frame model, just cut however short as needed), so if the new frame is on the shorter end (say, a 54 or smaller), then the insert is likely short enough that it would get completely discarded within the cut section and the remaining trimmed steerer wouldn’t look any different than a tube that never had the insert installed to being with. The problem would be if the new install was only slightly shorter, so that the cut length would go through the insert as well. Hard to say in that case how much of the threaded portion might be left to still tighten the top cap like it’s supposed to. The other option if it can’t be cut at the desired height because the insert is in the way, would be to leave it a bit long and take up the excess height w/ additional spacers above the stem instead of only below.
Depends on whether it’s an actual star nut (which is pounded in as Jim says, so it can only advance further one way and not ‘retreat’), or some other kind of anchor ~ a few of which are glued in (vs some sort of expander wedge type which is typically less secure, but removeable/adjustable). The 3T fork that came w/ my old Cervelo was the glue-in type, so while I don’t think it was that popular compared to some of the other options, they definitely came w/ some builds.
The key question then is how much the new owner would like to shorten it. If the steerer is truly “full length” from the factory, that’s usually tall enough for at least a 61cm frame (typically there’s only 1 fork across all sizes for a given frame model, just cut however short as needed), so if the new frame is on the shorter end (say, a 54 or smaller), then the insert is likely short enough that it would get completely discarded within the cut section and the remaining trimmed steerer wouldn’t look any different than a tube that never had the insert installed to being with. The problem would be if the new install was only slightly shorter, so that the cut length would go through the insert as well. Hard to say in that case how much of the threaded portion might be left to still tighten the top cap like it’s supposed to. The other option if it can’t be cut at the desired height because the insert is in the way, would be to leave it a bit long and take up the excess height w/ additional spacers above the stem instead of only below.
Does that description make sense?
Yes thanks
I honestly don’t know that it was glued in but assuming that it was…
it’s a size 61 frame. Buyer has not indicated precise desired length. But, seems like multiple options are available.
Tell him to just ride it long enough… my glued in sleeve broke free very frequently. I finally just bought an expander thingy.
I also had cut the the aluminum sleeve and pushed nut down.
Sounds like a bad bike shop. Or a bike shop not happy it didn’t sell a new bike.
What does the manufacturer say? That you better guess right because you have ONE SHOT at how much steerer tube you can have? A one cut option? Doubtful…
I bought a new bike this spring and needed/wanted to cut the excess steerer tube. It was my first experience with a star nut and aluminum insert. My star nut didn’t seemed to be glued. I can’t think of a reason why a manufacturer would glue a star nut in place. It’s designed in such a way that it only moves in one direction (down).
I found some good instructions on a few old ST threads. Once I was confident, I pretty much ended up doing what Jim describes in his #4 above. Instead of using a random bolt and hammer to drive the star nut deeper, I used an old too cap bolt I had lying around. I threaded it into the star nut, then drove it deeper. Once it was at the desired new depth, I cut through both the carbon tube and the alum insert.
Even if a star nut is glued to an alum insert, you should be able to break the glue/epoxy bond by tapping it down.
Is this on your Cervelo? The starnut is in the insert that’s glued into the fork. It can be cut through and depending on where they are cutting they might have to use pliers to get the starnut out. I had to do it once, it was a pain in the butt… but doable.
Is this on your Cervelo? The starnut is in the insert that’s glued into the fork. It can be cut through and depending on where they are cutting they might have to use pliers to get the starnut out. I had to do it once, it was a pain in the butt… but doable.
Yes, a 2018 (or 2019 I can’t recall but same specs regardless) P3
I can def see the buyer’s LBS being wary of f…cking around with the carbon fork that has an aluminum tube glued in. I’d do it myself but I am not a shop mechanic and worst come to worst I’ll just buy a new fork.
I can def see the buyer’s LBS being wary of f…cking around with the carbon fork that has an aluminum tube glued in. I’d do it myself but I am not a shop mechanic and worst come to worst I’ll just buy a new fork.
Thanks for input. Buyer says that LBS said it’s not doable. Period. Hard stop.
Yep, drilling a star nut is a great solution. Just start with a bit that is about the same diameter as the thread down the middle. Then keep drilling with larger and larger bits until you can pull it out with pliers.
The inserts I recall often have a lip at the top. So he could start by cutting 5mm off of the steerer to remove the lip, and then tap the starnut down. Either the starnut will move, or the insert will move. If the starnut moves first, great, tap it down to desired position and cut. If the insert moves first, install the fork and start stacking spacers and tightening the bolt to back it out of the fork, then put in a new one.
The devil is always in the details. Very likely the star nut could be either moved, removed, or drlled out/cut out, but it really depends on exactly where the sleeve is, where exactly the star nut is, and where exactly the rider or bike shop want to theoretically make the cut to the steerer.
What is important is that the star nut NOT be installed on or pounded through an unprotected carbon steerer tube. The star nut will severely score the inside of the carbon tube, and that will result in serious trouble later on. If the star nut is to be cut or drilled out, this has to be done very carefully if one hopes to keep that section of steerer tube (unless the star nut is inside the aluminum sleeve, then you don’t need to use as much caution).
I can def see the buyer’s LBS being wary of f…cking around with the carbon fork that has an aluminum tube glued in. I’d do it myself but I am not a shop mechanic and worst come to worst I’ll just buy a new fork.
Why would a bike shop be wary?
They would normally use a hacksaw to cut the steerer tube.
In this case, you would still use a hacksaw, but potentially you could be cutting through the star nut. It might take an extra couple minutes to get through it because it is steel. The carbon and aluminum cut like butter.
I can def see the buyer’s LBS being wary of f…cking around with the carbon fork that has an aluminum tube glued in. I’d do it myself but I am not a shop mechanic and worst come to worst I’ll just buy a new fork.
Why would a bike shop be wary?
They would normally use a hacksaw to cut the steerer tube.
In this case, you would still use a hacksaw, but potentially you could be cutting through the star nut. It might take an extra couple minutes to get through it because it is steel. The carbon and aluminum cut like butter.
The hard part is getting the sleeve out - it is epoxied in. When I did I cut below the star nut, and had maybe an inch of the sleeve left in the fork tube. I had to fully remove to stick another inset in. Getting that bit of sleeve out took a lot of time - epoxy was set good.
I can def see the buyer’s LBS being wary of f…cking around with the carbon fork that has an aluminum tube glued in. I’d do it myself but I am not a shop mechanic and worst come to worst I’ll just buy a new fork.
Why would a bike shop be wary?
They would normally use a hacksaw to cut the steerer tube.
In this case, you would still use a hacksaw, but potentially you could be cutting through the star nut. It might take an extra couple minutes to get through it because it is steel. The carbon and aluminum cut like butter.
The hard part is getting the sleeve out - it is epoxied in. When I did I cut below the star nut, and had maybe an inch of the sleeve left in the fork tube. I had to fully remove to stick another inset in. Getting that bit of sleeve out took a lot of time - epoxy was set good.
You didn’t have to remove the aluminum sleeve. Just install a new star nut in that one inch section.