Bicycle Mechanics - Tripple to double Crank?

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View Full Version : Tripple to double Crank?


wesGTZR
09-06-06, 06:33 PM
I'm intrested in changing my Tripple crank to a compact or even a regular double. My bike is five years old so I don't want to spend big $ on it. If I change to a double will I need a new shifter or a new FD(mine are both Tiagra). I think that the switch is doable if I just need a new BB and Crank. Also would this be a good time to change the chain and cassette.

Thanks.


barba
09-06-06, 07:23 PM
You would need a BB and crank (you can def. get the FD&RD to work, but I have no experience with Tiagra shifters), but I would not bother. It is a waste of money on any bike IMO, but particularly for one that is five years old. Just buy a double next time.

There are a million threads on this subject if you do a search.

capwater
09-06-06, 07:34 PM
Search this forum as well as cyclingforums.com. This topic gets debated at least once a month and there is no need to regurgitate the same info and clog up the server logs.


wesGTZR
09-07-06, 05:38 AM
Sorry, I should have searched. The last time I tried it was down, but I see it is working now. You are right it is a waste of money. I just like to tinker with things and thought this could buy me some time before I "need" a new bike. The main reason I would want to switch is better shifting and that I seldom use the 30 ring, but I think a 39 or 36 would give me all the low end needed with better and less shifting. I often resist going to the little ring by pushing the 42 because I know it would just be for 100 meters and right back up into the 42 ring.

grolby
09-07-06, 07:15 AM
Okay, let's just address a couple points here:

-A properly-adjusted triple does not shift any worse than a double. This is an awfully persistent myth. You won't get better shifting, especially not if you keep the same front derailer.

-If you don't use the 30, just don't use it. If you want to deny yourself even the temptation, adjust the limit screws on the derailer to make it impossible to shift to it.

-For the second time, a well-adjusted triple will shift just as well as a double, you're chasing a myth here.

I like to tinker myself, but this isn't worth tinkering with.

Phoible
09-07-06, 04:09 PM
you might be able to replace the 42 ring on your triple with a 39.

I recently got an ultegra (8 speed) crank/bottom bracket for about $40 shipped on eBay. Everything was in good working condition. So it might not be all that expensive.