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Discussion Starter · #1 ·
Hey

Back again with more cheapy questions. Please have pity on my 7 speed noobliness :D

Question 1:
Seems likely the next thing I have to look at is a crankset (3 chainrings). I have a 7 speed and there's not a lot of options around. From what I can gather searching on here, I should be able to use an 8spd or 9spd crankset. Did I get that right? Anything I need to watch out for?
(May also need a new BB to match, depending on the crankset, I guess).

Question 2:
When looking at the gearing options, I've checked up on my front derailleur specs, and can go for a max of 22T between top and bottom. I want to use all that, and most of the chainsets I've seen are 22T max difference. But when reading through the specs of my 7 speed rear derailleur it says 'Front chainwheel tooth difference : 20T' :eek:
Soooo confused. I don't really get why the rear derailleur would care how many teeth the front derailleur has?
Would it be OK to run with 22T difference on the FD when the RD says FD difference should be 20T? What would be the likely effects/problems?

Thanks again
 

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1) You can use pretty much whatever crank you want, many come with BB's

2) The RD takes up chain slack that is created when shifting between chainrings. That being said you can adjust chain length to compensate.
 

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Discussion Starter · #3 ·
Aaaaah! Now I get it. It's the chain that becomes the 'linking' factor and the RD can only take up so much 'slack' from the chain.

I'm off to read the excellent Post 2 in the Sticky "When to use a Long Cage vs Short Cage Derailleur? " and apply to my situation! :D

Cheers

lol i'm not allowed to even post links to this forum yet :madman:
 
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