Bicycle Mechanics - Double to Triple

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View Full Version : Double to Triple


TitaniuMerlin
01-20-06, 07:16 AM
When i got my bike, i was in fairly good shape (having ridden across Europe, London to Rome) but now that i am in College and all, i found that in the worst shape of my life. Biking, of course, is helping me not dwindle to far, and i plan on being in racing shape by march. My only problem is that my bike is a Double Chain Ring. I was wondering how easy (if at all possible) it is to change a Double to a Triple? Of course, i'd send it to a shop and have it professionally done, but i was wondering how complicated it was?


HillRider
01-20-06, 07:20 AM
It's not difficult but it can be expensive. You need a new crank and bottom bracket at a minimum. You will probably need a new front derailleur and most likely a longer cage rear derailleur to wrap the extra chain length. Depending on the make and model shifters you have, you may need a new front shifter.

TitaniuMerlin
01-20-06, 07:32 AM
Hmm...sounds complicated. How expensive would such a thing be? All my componenets are Shimano...forget which one, but they are all the same. Would it be easier if i was to contact the store and see what they say?


TallRider
01-20-06, 07:51 AM
If you've got Shimano STI brake/shift levers, and the left one (that shifts the front derailler) is designed for a double-chainring crank, you'll need to update. Bar-end shifters or down-tube shifters, you won't need to update your shifters.

The far cheaper way to hold yourself over until you get back into racing shape is just to buy a wider-spaced cassette. If you're currently running a 12-23, buy a 12-27 or 13-28 or something like that. Then, once you're in racing shape, put your tighter cassette and its smaller gears back on your bike. You'll need to spring for a cassette lockring tool (around $5) and a chainwhip (around $10) to hold your cogs while loosening the lockring.

HillRider
01-20-06, 09:19 AM
If you have Ultegra or 105 9-speed STI shifters, they are both double and triple compatible. The older 8-speed and newer 10-speed shifters are specific to either double or triple.

As Tim mentioned, downtube and barend front shifters are not indexed and will shift anything.

How expensive? Depends on what group you want to use and what, if anything, you can get used or NOS.

Applehead57
01-20-06, 09:22 AM
I like timcupery's idea about the cassette.

It's a heck of a lot cheaper, probably no other expense than the cassette.
And, you can change it yourself, if you want to swap them to match your days riding.
If you buy it at your LBS, they'll change it for you, probably for free. It's very quick.

Deanster04
01-21-06, 12:36 AM
Try eBay for shimano Triple parts. Frequently see them for sale.

Deanster04
01-21-06, 12:39 AM
In addition, you might check to see what the largest cog is that you have on your wheel. You might go to a lower gear combination by changing the Small chain ring on the front and get a new cassette and or freewheel depending on the age or your group. You would need a new chain properly sized. That is the cheapest solution.

Retro Grouch
01-21-06, 05:21 AM
You might be real a good candidate for a compact 50/34 crank set. If you get one that matches your current bottom bracket the crank might be the only thing that you'll have to buy.

John E
01-21-06, 07:59 AM
You might be real a good candidate for a compact 50/34 crank set. If you get one that matches your current bottom bracket the crank might be the only thing that you'll have to buy.
That's a good place to start. If one of your derailleurs cannot handle a 16-tooth drop in front, consider 48-34. With a 13T small cog in back, this still provides an adequate 100-inch top gear. You can buy an old school (non-compact) mountain crank and mount 48 and 34 tooth rings on the two outer (110BCD) positions, leaving the granny ring mounting holes unpopulated.

TitaniuMerlin
01-24-06, 06:49 AM
I'll have to wait until my folks deliver my bike up to me. At college, so it went home for the winter. I asked my dad to go into the local bike store and talk to them about it (at about the same time i made the original post) but i have yet to hear back from him.

I am personally not very savy when it comes to bike parts and all, and mainly got my bike (a 2001 Titanium Merlin Road) 2 years ago due to the fact that it was only going to cost me 1/3 the original price and i was in prime shape at the time and could easily manage the double. There have been days riding out here where the grade of the hills has been so steep that i can hardle turn the peddles and make it up. Which is why i want to switch over to a good old triple, as i also dont know how much racing i'll be doing.

TitaniuMerlin
01-27-06, 06:34 AM
Talked to my LBS (the one i got the bike from) and they said not to change it from a double to a triple. Rather, they'll put on a smaller one in the front (front derailleur i believe - my mom wasnt very clear on the details since she doesnt know anything on the subject) which will hopefully be done soon so i can get riding. Should make it easier for me to get up the hills.