No, it is not possible because 10-speed derailleurs are non-compatible with 11-speed cassettes. the main difference is the tensioning of the cables of shifters, which are of 10-speed based on a 10-speed derailleur, but 11-speed cassettes are larger and bigger in size, smaller speed derailleurs are not compatible with the larger sized cassettes, it is the main issue of this of non-compatibility. derailleur contains two screws that are used to adjust the tensioning and stretching of gear cables and also these screws are used to adjust the lateral and longitudinal movement of the derailleur. also when you want to change gear from smaller to higher and higher to smaller cogs of the cassette, the chain would not work better and accurately in this setup.

## Difference Of Gear Shift Ratio:

The gear ratio of 10-speed and 11-speed derailleurs are not the same and not compatible with each other, it is the main difference that has made this setup non-compatible with each other, the value of the gear shift ratio of 10-speed derailleurs is greater and is 1.2, on the other way gear shift ratio of 11-speed derailleurs is 1.1, this is the major difference which has differentiated gear pull ratio between the cables, derailleur, and cassettes of 10-speed and 11-speed bikes.

## Difference In Cassette Width:

11-speed cassettes are thicker in diameter as compared to 12-speed cassettes, this difference is easily recognized by highlighting the width and diameter of the chains of both of them. due to which the difference between the spacing of both of the cassettes is not equal, 12-speed cassettes do not contain any extra sprocket and cog when we compare it with the 11-speed cassettes. but the difference in spacing is not much larger or greater, when you are installing a cassette in your bike the first thing you have to look for is spacing, a 10-speed cassette has a spacing of 3.90mm, and an 11-speed cassette has a spacing of 3.95mm. this difference is just 5mm, this difference is made compatible by installing spacers on both the drive and non-drive sides of the rear wheel.

## Derailleur Movement:

The main part of your that needs to be adjusted and maintained accurately is the 10-speed derailleur, accurate the stretching ratio of the ratio, and judge the movement of the derailleur by shifting and indexing of gears, this setup totally depends on the derailleur, it works accurately if you can give it few more time in its maintenance, there are few screws of derailleur and few screws of gear cable, these screws need to be adjusted properly.

## Value Of Pull Ratio Of 10-speed And 11-speed Derailleurs And Shifters:

The value of spacing of both 10 and 11-speed derailleurs is 3.9 as I have described above in my post and gear shifter ratios of the 10-speed cassette are 1.2 and 11-speed derailleurs are 1.1. you have to divide the value of spacing and the gear shift ratio of both 10-speed and 11-speed derailleurs, and the answer will be a clear-cut value of the cable pull ratio, which will clearly identify the difference between both 10 and 11-speed derailleur, cassette, and shifters.

Now we will divide the value of spacing and cable pull of the 10-speed derailleur:

The value of spacing is 3.9mm

The value of cable tensioning of the 10-speed derailleur is 1.2

Now divide both of these values 3.9/1.2

The answer you will get is 3.25millimeters.

it is the mathematics and calculation of the cable pull ratio of a 10-speed derailleur, now we will the same calculations for an 11-speed derailleur.

The value of the spacing of the 11-speed derailleur is 3.9mm.

And the value of the cable pull of the 11-speed derailleur is 1.1.

Now divide both of these values 3.9/1.1 When you divide both of these values you will get the answer of 3.54millimeters.

Now we are finding the exact value of the lateral and longitudinal movement of the derailleur, the derailleur moves with the help of the gear shifters, and these shifters will produce movement and pulse within the cables of the shifters, it means what should be the exact value of cable pull of both 10 and 11-speed derailleurs?

To find the value of the cable we have to multiply the value of the cable pull ratio of the 11-speed derailleur which is 3.54 with the 11, because the derailleur is 11-speed, and the stretching and tensioning value of an 11-speed derailleur should be 39millimeters.

Now, 39mm is the value of the cable pull of an 11-speed derailleur, in this setup where you want to install a 10-speed derailleur with the 110-speed cassette, then multiply the value of the cable pull of the 10-speed which is 39*1.2= 46.8mm, it is the value of the cable pull for a 10-speed derailleur, multiply the same value 39 with the value of cable pull of 11-speed derailleur:

39*1.1=42.9.

Now you have values of both 10 and 11-speed derailleurs and you can easily identify the cable pull and difference.

Minus both of these 10 and 11-speed cable values

46.8-42.9= 3.9mm.

If you are using an 11-speed gear shifter with a 10-speed derailleur, then when you want to shift your chain in the higher 10th cog of the cassette, it should actually be in the 11th sprocket according to the working principle of your 11-speed shifter, but it will confuse you a little bit by giving an extra click of sound during the shifting of gear by shifters, but actually, you have to ignore that click sound because the chain will be in higher sprocket or higher cog of your cassette.

## Conclusion:

This theory proves that the 10-speed derailleur along with the 10-speed gear shifter works accurately and normally along with the 11-speed cassette. but as you know 10-speed shifter contains 10 gears while an 11-speed shifter contains 11-speed gears so you will lack a single gear, if you are going to install a 10-speed derailleur, 10-speed gear shifter, and 11-speed cassette.