Bicycle Mechanics - 25 cog to 27 cog derailleur question

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Dutchy

07-23-03, 01:06 AM

I am contemplating doing the Alpine Classic 200km ride next year and am thinking I should get a 27 cog for the very long ascents through the snow fields. I am a strong climber but I think a 27 will be handy as a bail out gear, considering this ride happens in summer.
I run Ultegra 9spd and want to know if I need to lengthen the chain or change derailleur to go from a 25 cassette to a 27.
I am guessing it will work without any problems but just need someone who has experience to confirm my theory.

Thankyou.

Mark

sch

07-23-03, 11:59 AM

It may not be advisable to use the 53t CW with the 27t cassette but you will just have to eyeball the bike to see how it looks after the change without lengthening the chain. There is only 1" difference. The short derailleur should handle the 27t cog without difficulty. The long derailleur is for the triples.
Steve

Dutchy

07-23-03, 10:32 PM

OK, I'll give it a try.

Thanks.

Mark