|What difference between shimano HG and IG cassettes ?||PeterRider|
Feb 1, 2002 10:32 PM
|And also, are all shimano mtb cassettes IG ?
What is also the difference between HG50, HG70, HG90 ?
If this makes a difference, I am asking about 8spd stuff.
|re: What difference between shimano HG and IG cassettes ?||TJeanloz|
Feb 2, 2002 8:00 AM
|The difference is in the ramping, HG cassettes are ramped on one side of each cog, IG are ramped on both sides of each cog. IG was supposed to be an improvement on HG, but it never really caught on.
I believe (but could be totally wrong) that IG was limited to 7 speed cassettes- everything 8 and 9 speeds is HG. Shimano claims that you need to use an IG chain with an IG cassette and an HG chain with an HG cassette, but mixing them often works.
The difference between HG50, HG70 and HG90 is quality. It roughly follows the 105/Ultegra/Dura-Ace split. They use the numbers so that they can produce one chain (say HG70) for both XT and Ultegra.