Hey guys, today I'm going to upgrade the drivetrain of this hybrid bike
Trek 720 Multitrack
From 7-speed to 10-speed
So here I have a SRAM Red 11-26t cassette
SRAM X7 shifters
A SRAM X7 front derailleur and a SRAM X7 rear derailleur
Let's go ahead, take off the back wheel and install the new cassette
The spacer is not needed for 10-speed cassette
The X7 rear derailleur couldn't shift to the biggest cog
because it's a 9-speed derailleur and it's not compatible to 10-speed drivetrain
So what I've got here is a SRAM Force 22
I like this one better because it's lighter and shifts smoothly
It features exact actuation that delivers 3mm shifts in every gear