Originally Posted by Fishboy
I'm still running 8 speed Shimano drive components. I'm thinking of upgrading to 9 speed since it's time for a new chain, cassette, and chain rings. My old 8 speed rings are not marked A or B type. What is the difference between the type A and B rings?
I already bought some Vuelta 9 speed chainrings that are not marked A or B type like the Shimano rings. If I decide to stick with 8 speed, can I use the Vuelta 9 speed rings with the wider 8 speed chain?
Also, I have an Ultegra rear derailluer (8 sp.) with Carmichael aluminim pulleys. I've been told this setup is compatible with 9 sp chains and cassettes by my LBS and shouldn't need to be changed. Is he right?
From my
Bicycle Glossary:
In Shimano road chainrings, "A" designates 39 tooth, "B" designates 42 tooth.
All 42s are "A"s; All 39s are "B"s by definition.
There are two kinds of 53s:
"A" type that is intended to be used with a 42
"B" type, which is intended to be used with a 39
If you have poor shifting skills, matching the chainrings by the letters will give slightly better shifting, but if you're a reasonably skilled cyclist, it really doesn't matter.
You can use any 130 BCD chainrings. See:
http://harriscyclery.com/130
Derailers don't care how many speeds, when they talk about "8-speed" or "13-speed" derailers that's just marketing hype.
Sheldon "Not Rocket Science" Brown
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| The race is not always to the swift, |
| nor the battle to the strong |
| -but that's the way to bet. |
| --Damon Runyon |
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