chain tensioner at end of derailer?
#1
Part-time epistemologist
Thread Starter
chain tensioner at end of derailer?
Hi ... I saw the following in the MIT V8 thread
To me it looks like a chain tensioner attached to the end of the tension pulley. Since it's a Brompton clone, I assume it's needed when the bike folds given that the distance between the derailer and crank decreases.
However I imagine that it could have other uses as well. The derailer in the picture might be a short cage rear derailer to minimize the chance of striking something on the ground. The additional chain tensioner could pick up additional slack from the length of chain needed for the triple.
Does anyone know what that thing is and where one might get one?
To me it looks like a chain tensioner attached to the end of the tension pulley. Since it's a Brompton clone, I assume it's needed when the bike folds given that the distance between the derailer and crank decreases.
However I imagine that it could have other uses as well. The derailer in the picture might be a short cage rear derailer to minimize the chance of striking something on the ground. The additional chain tensioner could pick up additional slack from the length of chain needed for the triple.
Does anyone know what that thing is and where one might get one?
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#2
Banned
Fabricate , DIY.
apparently nobody even imports the whole 'mit' bike to the US let alone the parts ..
suntour decades ago made a 3 pulley cage
over on the I BoB list someone demo'd how they modified an existing RD .. they made the parts themselves.
a drill and a jewelers hand saw hand files and time can make things..
though the CAD CAM and 3D printer is now the other end of the Tech spectrum now.
apparently nobody even imports the whole 'mit' bike to the US let alone the parts ..
suntour decades ago made a 3 pulley cage
over on the I BoB list someone demo'd how they modified an existing RD .. they made the parts themselves.
a drill and a jewelers hand saw hand files and time can make things..
though the CAD CAM and 3D printer is now the other end of the Tech spectrum now.
#4
Banned
Like I said, Its so low to the ground it could be a kickstand ..
It's why an IGH makes so much more sense than a long cage RD on a small wheel folding bike ..
It's why an IGH makes so much more sense than a long cage RD on a small wheel folding bike ..
#5
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Can't the one from a birdie be used. That's unobtainable also?
#6
Banned
Brompton's 3 speed if the chain length is right, (Fairly short) tucks right up high .. ..
then for me, the low gear is the 2nd range in the Mountain drive crank 54/21.6t [ a 50/20 is even numbers]
though running a 110 BCD speed-drive the 34t acts like a 54t when kicked in overdrive
(but chain never moves, 1 cog 1 chainring.) .
then for me, the low gear is the 2nd range in the Mountain drive crank 54/21.6t [ a 50/20 is even numbers]
though running a 110 BCD speed-drive the 34t acts like a 54t when kicked in overdrive
(but chain never moves, 1 cog 1 chainring.) .
#7
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What's wrong with dual short cage derailleurs? It's such a simple arrangement and I bet it would work great.
Last edited by BassNotBass; 04-10-14 at 04:31 PM.
#8
Part-time epistemologist
Thread Starter
I think that the original picture in the thread had a Shimano SS or GS road derailer. I can't tell for sure.
There are reasons to pick something other than an IGH.
There are reasons to pick something other than an IGH.
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A narrative on bicycle driving.
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#9
Part-time epistemologist
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That's interesting.
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A narrative on bicycle driving.
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#12
The Recumbent Quant
#13
Part-time epistemologist
Thread Starter
Three derailers?!?
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A narrative on bicycle driving.
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