mvnchi
New Member
First and foremost hello!
This topic probably has been seen and talked over and over. At least that's what it appeared to me when searching.
Sadly i couldn't really find any answer to my questions really from reading the dialogues.
SO.. on my old Gazelle V3.0 Roadbike i got a SRAM Elita Triple 50/39/30T 10-speed currently with a 12-28 casette and was planning to convert it to a double because unless i would approach really steep and especially longs climbs i would almost never use the granny gear.
My idea was to turn it into a 50/38T with a 12-30 casette which would give me a transmission ratio low enough to still be able to climb most hills here. Also the gear steps would fit me better.
Using a online gear calculator i was looking at the following:
But since i was planning on keeping the triple crankset the chainline would remain unchanged.
Meaning that the 38/30 Gear for example would be "forbidden" unfortunately.
Another idea was to do it the other way around. A 50/36.
So dropping the outside 50T and getting a 50T as inside/middle chainring and replacing the granny 30T gear for a bigger 36T. Then in theory i would get "lower" ratios and down to the largest cog.
But in return i would sacrifice the 50/12 which i don't really want to as i tend to spin out quite often going downhill already.
So sticking to the initial idea of going with a 50/38 12-30 and the triple crankset - is there anyway to still be able to use the 38/30 and get the chainline somewhere so it is like the mid table?
Would i need smaller bottom brackets? Is it anyways always going to case chain skew/rub due to cross chaining? Or am i completely wrong here?
Anyone willing to sacrifice some time for my nonsense.. thanks in advance!
This topic probably has been seen and talked over and over. At least that's what it appeared to me when searching.
Sadly i couldn't really find any answer to my questions really from reading the dialogues.
SO.. on my old Gazelle V3.0 Roadbike i got a SRAM Elita Triple 50/39/30T 10-speed currently with a 12-28 casette and was planning to convert it to a double because unless i would approach really steep and especially longs climbs i would almost never use the granny gear.
My idea was to turn it into a 50/38T with a 12-30 casette which would give me a transmission ratio low enough to still be able to climb most hills here. Also the gear steps would fit me better.
Using a online gear calculator i was looking at the following:
- Green Numbers are suggesting no chain skew/rub, yellow numbers are duplicates and red numbers are forbidden sprockets.
- With the 50/38 12-30 i would (theoretically) get almost down to the same transmission ratio of my 30T granny gear.
- They are calculating with a wheel circumference of 211cm
But since i was planning on keeping the triple crankset the chainline would remain unchanged.
Meaning that the 38/30 Gear for example would be "forbidden" unfortunately.
Another idea was to do it the other way around. A 50/36.
So dropping the outside 50T and getting a 50T as inside/middle chainring and replacing the granny 30T gear for a bigger 36T. Then in theory i would get "lower" ratios and down to the largest cog.
But in return i would sacrifice the 50/12 which i don't really want to as i tend to spin out quite often going downhill already.
So sticking to the initial idea of going with a 50/38 12-30 and the triple crankset - is there anyway to still be able to use the 38/30 and get the chainline somewhere so it is like the mid table?
Would i need smaller bottom brackets? Is it anyways always going to case chain skew/rub due to cross chaining? Or am i completely wrong here?
Anyone willing to sacrifice some time for my nonsense.. thanks in advance!
Last edited:
@mvnchi