Should Road-Conversions Utilize Road Cranks?
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Should Road-Conversions Utilize Road Cranks?
I have been building up a 130mm rear spacing road bike for fixed-gear, and was simply planning on getting an IRO drivetrain to start with. But I forgot to consider chainline and things like that and now I'm not so sure about my choice. Chain-line and BB size are things I have trouble understanding, I can't visualize it in my head so it's difficult.
With 130mm rear-spacing, what sort of things should I be thinking about? Should I use road cranks with one chainring to achieve a better chainline? I've read some threads using the search function but like I said, it's mind-bending. The BB is a standard 68mm English thread (It's a GT Strike road bike).
Anyone have any ideas on how I can get a nice balance of chainline with either track or road parts?
With 130mm rear-spacing, what sort of things should I be thinking about? Should I use road cranks with one chainring to achieve a better chainline? I've read some threads using the search function but like I said, it's mind-bending. The BB is a standard 68mm English thread (It's a GT Strike road bike).
Anyone have any ideas on how I can get a nice balance of chainline with either track or road parts?
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What hub do you want to use? Flipflop or not?
Chances are that it will have a 42 mm chainline. See if your chainstay allows you to go 42mm with the chainring you want. If it does, go 42 for simplicity. Track bb and track crank.
However, getting a road crank and a shortish bb will prolly be cheaper. 45ish chainline, which is a bit trickier to match with your hub.
Chances are that it will have a 42 mm chainline. See if your chainstay allows you to go 42mm with the chainring you want. If it does, go 42 for simplicity. Track bb and track crank.
However, getting a road crank and a shortish bb will prolly be cheaper. 45ish chainline, which is a bit trickier to match with your hub.
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Sometimes a track crank will hit the chainstay on road frames with a short BB.
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There's aways flipping the bracket over so the left side (shorter) is on the right...that often works, though it's often easier if you have an old-school spindle bracket and a box full of other ones to try.
Trial and error are integral parts of bike mechanics.
Trial and error are integral parts of bike mechanics.
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Originally Posted by thurstonboise
Sometimes a track crank will hit the chainstay on road frames with a short BB.
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what road crank do you plan on using? There are online databases for cranks and chainline. That should help you deterine what BB will give you a 42mm chainline.
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Originally Posted by mihlbach
what road crank do you plan on using? There are online databases for cranks and chainline. That should help you deterine what BB will give you a 42mm chainline.
The other option is a Centaur Ultra-Torque crankset (one-ring obviously). I hear the difference between those cranks and regular ones is quite noticeable and I'd like to try it with a fixed gear or singlespeed.
If those two options turn out to be too much of a hassle, I'll probably get an IRO drivetrain.
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The bottom bracket will probably be quite low so you want to go for 165 mm long to avoid pedal strike in corners. Not sure but you may have better luck finding that length with track gear? most road cranks are 170-175. Not sure what is available to you.
I have 165's on my road conversion and no worries until I tried racing, which was very scary in the bends!
I think Sheldon Brown has some measurements regarding sprockets, rings, and chainline. I just ordered my stuff and was lucky.
I have 165's on my road conversion and no worries until I tried racing, which was very scary in the bends!
I think Sheldon Brown has some measurements regarding sprockets, rings, and chainline. I just ordered my stuff and was lucky.
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save yourself some money and just get a shorter bb
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Originally Posted by BostonFixed
IMO, road cranks are far superior to track cranks in every way.
How many ways are there for a crank to be "superior?" They're not lighter, they're not stiffer, they're not stronger... May be prettier...
They also commonly use the semi-obsolete 144 mm bolt circle, for which chainring selection is rather poor and the rings available tend to be unreasonably expensive due to their rarity.
Sheldon "Cranks Don't Really Know Where They're Being Ridden" Brown
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Originally Posted by Sheldon Brown
Could you be more specific?
How many ways are there for a crank to be "superior?" They're not lighter, they're not stiffer, they're not stronger... May be prettier...
They also commonly use the semi-obsolete 144 mm bolt circle, for which chainring selection is rather poor and the rings available tend to be unreasonably expensive due to their rarity.
Sheldon "Cranks Don't Really Know Where They're Being Ridden" Brown
How many ways are there for a crank to be "superior?" They're not lighter, they're not stiffer, they're not stronger... May be prettier...
They also commonly use the semi-obsolete 144 mm bolt circle, for which chainring selection is rather poor and the rings available tend to be unreasonably expensive due to their rarity.
Sheldon "Cranks Don't Really Know Where They're Being Ridden" Brown
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hey wait I have old school road cranks that are 144bcd what should I do??? hehehh
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Originally Posted by BostonFixed
I think you read my statement backwards.
yrroS
nodlehS