Great work, so happy your video popped into my feed. I look forward to seeing even more parts measured in the future. Would also love to see a list/compilation of all your shifter/derailleur pull measurements 😊
I've been compiling a spreadsheet of derailleur pull ratios and shifter cable pulls here: docs.google.com/spreadsheets/d/1uxu7OSKLG3JzhmOIg-iWHz-p8MW0ou0HCLRWk4BoO04/edit?usp=sharing Compatibility is a bit more tricky. My measurements can help you figure out what /might/ work, but the only way to figure out what does work is to try it out. That being said, Russ at @PathLessPedaledTV is doing a great job of experimenting with different shifters and derailleurs to discover what is compatible.
Do you have any thoughts on why the cable pull ratio you measured wasn't the same as the GRX 10-speed RX400 you measured? Both of these RD's are exchangeable with GRX 11 & 10 speed shifters, Dura-Ace & Ultegra & 105 11sp shifters, and Tiagra 4700 10sp shifters. How much cable-pull ratio difference matters?
The Ultegra RD-RX800 derailleur appears to be a bit of an outlier, having a higher pull ratio than I would expect. I haven't published the video yet, but the 105 RD-5800 has the same pull ratio as the GRX RX400. Both the RD-RX800 and the RD-5800 are officially compatible with the same ST-R8020 shifter, but have significantly different pull ratios. I'm still trying to understand why Shimano designed this derailleur this way. My main theories are: - Improved chain control by really pressing the chain against the side of the cog - New ideas at Shimano on how to improve shifting My earlier video "The Problem with Traditional Compatibility" talks about how much pull ratio matters, but manufacturers will generally design the drivetrain so that the result of multiplying the cable pull and the pull ratio is anywhere from 5% lower than the cog pitch to 2% higher than the cog pitch, with about 2% lower than the cog pitch being the average.
Great work, so happy your video popped into my feed. I look forward to seeing even more parts measured in the future. Would also love to see a list/compilation of all your shifter/derailleur pull measurements 😊
Bro this is insane, i was about to say, do a polyfit, but you did it in the end, i did not know it was a exponential curve, nice
Plz do this to a sram eagle
Really interested to see this one is so far different from the GRX RD-RX400. Perhaps due to wear?
Is there a table of derailleurs and shifters, their pull ratios and compatibility?
I've been compiling a spreadsheet of derailleur pull ratios and shifter cable pulls here: docs.google.com/spreadsheets/d/1uxu7OSKLG3JzhmOIg-iWHz-p8MW0ou0HCLRWk4BoO04/edit?usp=sharing
Compatibility is a bit more tricky. My measurements can help you figure out what /might/ work, but the only way to figure out what does work is to try it out. That being said, Russ at @PathLessPedaledTV is doing a great job of experimenting with different shifters and derailleurs to discover what is compatible.
Do you have any thoughts on why the cable pull ratio you measured wasn't the same as the GRX 10-speed RX400 you measured? Both of these RD's are exchangeable with GRX 11 & 10 speed shifters, Dura-Ace & Ultegra & 105 11sp shifters, and Tiagra 4700 10sp shifters. How much cable-pull ratio difference matters?
The Ultegra RD-RX800 derailleur appears to be a bit of an outlier, having a higher pull ratio than I would expect. I haven't published the video yet, but the 105 RD-5800 has the same pull ratio as the GRX RX400. Both the RD-RX800 and the RD-5800 are officially compatible with the same ST-R8020 shifter, but have significantly different pull ratios.
I'm still trying to understand why Shimano designed this derailleur this way. My main theories are:
- Improved chain control by really pressing the chain against the side of the cog
- New ideas at Shimano on how to improve shifting
My earlier video "The Problem with Traditional Compatibility" talks about how much pull ratio matters, but manufacturers will generally design the drivetrain so that the result of multiplying the cable pull and the pull ratio is anywhere from 5% lower than the cog pitch to 2% higher than the cog pitch, with about 2% lower than the cog pitch being the average.