Perhaps that is why the very top is thinner and takes that smaller clamp. On the other hand, I find it hard to believe that this carbon tube is that complex of an engineering feat. It’ll also be clamped on the outside by a seatpost clamp and have the post inside of it.
@jame5on yes, I can limit travel, but the point is to have more travel and to have the limit of that travel be 2 cm lower than it currently is.
What were you cutting tho?
Gosh, I want an old cracked carbon part to practice on and observe. The park tool video dudes cutting seatpost masts just do it like they would cut a steerer, using a hacksaw blade and a guide.
If I go through with this, I’ll probably use a dremel like the worldwide cyclery guy did. Gonna swing by the lbs and ask if they have any broken carbon parts I can gave lol.
the cutting part is going to be nothing
it’s what you’ll be left with that may or may not be useful to you
your plan is to just put a bigger seatpost collar farther down the tube?
like mentioned above, they designed a portion to be clamped to and made it a consistent size all the way around. I wouldn’t be interested in clamping farther down but hey if someone else did it somewhere, scratch the itch
I might have the top of my stearer in a drawer
Isn’t further down tapered? Is tightening going to make it want to slide off?
When I dremmeled my stearer it was not very pretty around the rim. Tried to use a hose clamp as a guide and drummer cutter went through the hose clamp easier than the carbon
That was also my experience dremeling a metal steerer recently. I’d be more careful here lol.
Now you’ve got me thinking about whether I’ve got some carbon steerer laying around…
Yeah, I measured the section where I want to clamp to 36.4mm and test fit the clamp that I purchased (see scuffs in photo) so I’m hypothesizing that it is some standard thicker seat tube layup. The post will also be bottomed out at the collar, so the only clamping force required is to keep it from spinning laterally.
You’re only taking 2cm? Seems like unnecessary risk for marginal gains. How much less will the saddle get in the way 2cm lower? Can you just buy a post with a smaller max insertion to saddle rail dimension?
2cm is a vast difference when it comes to your saddle position. In addition, the new post make more efficient use of the stack between the seat tube and rails. Part of the point is also to complete an unspeakable bike project.
But I made some discoveries. Namely that my current seatpost only has 150mm of travel! I think that I could get that number up to 180 with no chopping due to the OneUp post’s more efficient use of space. It isn’t quite the 210 I wanted, but would probably be cromulent enough.
I think that I could sneak a 210 in there, but it gets close to where the seat tube bends:
Which kind of tempts me even more. Use of space would be absolutely MAXIMIZED (though for 210mm of travel I’d have to take 34mm off the top 
)
Instead of hacking your frame, maybe you could hack together a bmx pivotal x dropper and get maximum clearance
I was thinking also that maybe someone in the area can go look at this for me and I could return the new dropper post and the $100 of cutting implements I bought to put that money toward the frame instead lol
If I install the sram automatic coaster hub I just brought on a vertically dropped out bike, can I use a fixed singulator device to tension the chain, and still do back-pedal braking?
I doubt it would work well, if at all.
The coaster hub will need a certain amount of reverse pressure to brake and the tensioner will try and take up that reverse pressure.
the chain would go slack on the top when backpedaling
choose a magic gear instead to get the tension, usually pretty possible especially with a half-link in the chain
I hope that version is better than the torpedo duomatic i had years ago. It was not a great riding experience. Paid $30 for the hub in 2008 and sold it built up for $130 18 months later
I guess it depends how solid the tensioner is. The one I normally use is locked in place, but back pedal pressure might over-load it. The sram ones seem to have a reasonable reputation I think @Blakey . Maybe I will go thru the bins and look for an old track bike…
Doesn’t the braking force on a coaster want to rotate the wheel out of the drops?
I had a 6 bolt fixed gear set up with one of these tensioners, worked just fine.
Ah, I see. I was thinking of a spring-loaded tensioner. Today I learned about this solid-mount kind.
