can you guys please explain me how i can use road frames on fixed gear? and what is the problem with geometry and drops? i really like old steel frames, but njs is a bit expensive for me
can you guys please explain me how i can use road frames on fixed gear? and what is the problem with geometry and drops? i really like old steel frames, but njs is a bit expensive for me
You shouldn’t have any issues using a frame with horizontal or semi-horizontal drops such as the one pictures. Chain tension is usually the issue when the dropouts are vertical only, as there is no way to position the rear wheel backwards or forwards to provide proper tension on the chain. This one looks good. You may need to adjust the chainstay spacing at the dropouts to fit a 120mm track wheel though, easily doable with some hardware store nuts, washers, and threaded rods.
gumption_boy on
As with all things, there’s a rabbit hole, but here are the basics:
1) Most fixed gear hubs are 120mm wide. Most road bikes don’t have a dropout spacing of 120mm, which results in needing to either reset the frame (steel frames only), or re-space the hub (much easier in most cases). Some older road bikes ARE 120mm however, so you might get lucky.
2) Unlike road bikes, fixed gears always have the chain in the same position and it’s important that the chain be as straight as possible between the cog and chainring. This is known as chainline, and getting it straight is usually as simple as choosing a bottom bracket that’s the right length.
3) Track bikes usually have aggressive geometry and are a lot more nimble (and in some cases, twitchy) than road bikes, especially older steel road bikes. This is ultimately a matter of comfort and preference, though, as some riders may prefer that more relaxed feel.
4) The one place where geometry might be an issue is a lower BB height on road frames. Since fixed pedals are always turning, you can’t just keep one foot up when leaning into corners. Track specific frames account for this with a higher BB shell, but road frames don’t and are more susceptible to pedal strike. Just dont use super long cranks or corner really aggressively and this won’t be an issue.
Hope this helps.
bleuhours on
man we need a thread for this if it doesn’t already exist
spanish42069 on
There is no issue, horizontal dropouts are fine. The geo will be a bit more relaxed than a track frame but thats personal preference.
7 Comments
I usually just pedal my bice
Convert drops to fixed appropriate drops thru welding. (Atleast that’s how I did mine.)
https://www.sheldonbrown.com/fixed-conversion.html
You shouldn’t have any issues using a frame with horizontal or semi-horizontal drops such as the one pictures. Chain tension is usually the issue when the dropouts are vertical only, as there is no way to position the rear wheel backwards or forwards to provide proper tension on the chain. This one looks good. You may need to adjust the chainstay spacing at the dropouts to fit a 120mm track wheel though, easily doable with some hardware store nuts, washers, and threaded rods.
As with all things, there’s a rabbit hole, but here are the basics:
1) Most fixed gear hubs are 120mm wide. Most road bikes don’t have a dropout spacing of 120mm, which results in needing to either reset the frame (steel frames only), or re-space the hub (much easier in most cases). Some older road bikes ARE 120mm however, so you might get lucky.
2) Unlike road bikes, fixed gears always have the chain in the same position and it’s important that the chain be as straight as possible between the cog and chainring. This is known as chainline, and getting it straight is usually as simple as choosing a bottom bracket that’s the right length.
3) Track bikes usually have aggressive geometry and are a lot more nimble (and in some cases, twitchy) than road bikes, especially older steel road bikes. This is ultimately a matter of comfort and preference, though, as some riders may prefer that more relaxed feel.
4) The one place where geometry might be an issue is a lower BB height on road frames. Since fixed pedals are always turning, you can’t just keep one foot up when leaning into corners. Track specific frames account for this with a higher BB shell, but road frames don’t and are more susceptible to pedal strike. Just dont use super long cranks or corner really aggressively and this won’t be an issue.
Hope this helps.
man we need a thread for this if it doesn’t already exist
There is no issue, horizontal dropouts are fine. The geo will be a bit more relaxed than a track frame but thats personal preference.