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?
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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.
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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
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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 $130 18 months later
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I guess it depends how solid the tensioner is. The one I normally use is locked in place, but back pedal pressure might over-load it. The sram ones seem to have a reasonable reputation I think @Blakey . Maybe I will go thru the bins and look for an old track bike…
Doesn’t the braking force on a coaster want to rotate the wheel out of the drops?
I had a 6 bolt fixed gear set up with one of these tensioners, worked just fine.
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Ah, I see. I was thinking of a spring-loaded tensioner. Today I learned about this solid-mount kind.
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Pushing hard against the pedals puts a tremendous amount of force on that tensioner. I guess if you only brake gingerly with the coaster hub you might be fine but I’m pretty confident it will get mangled if you stomp the pedals.
Intuitively I’d say a sprung tensioner would be better than a fixed one. It would only flop around instead of breaking. My first choice would be a magic gear for sure.
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Funny I just picked up a (used, already built into a wheel) Sturmey-Archer S2C, which is 2-speed kickback with coaster brake.
Word on the street is the early ones had a manufacturing issues, and that in general it’s a good idea to open them up, make sure there isn’t any metal floating around in the grease, clean, regrease, check pawl tension.
So that’s what I’m going to do, and I’d imagine it wouldn’t hurt with your SRAM one either.
Definitely not using a tensioner, but mine will be the only brake on the bike.
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Cheers. Yeah i did a bit of research on them about 10 years ago, the various types, but couldnt justify the cost. For 50$ NOS it was too good to pass on. The sturmey archer always sounded like real fun.
I have a bin of random Sturmey Archer small parts in the cabinet of small parts I got when Harris Cyclery closed. Let me know if you need anything for your rehab project.
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