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Discussion Starter · #1 ·
Hi first post here. I'm looking at getting my first road bike and I have been to the local shop checking bikes out 2 times so far and nobody has really given me an answer of what is the diffrence between the double and triple setups? Can somebody help me out with this?

Right now I'm leaning toward the Allez road bike.

Thanks
 

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The idea is that the triple gets you more gears, and therefore, you have more room on the low end in the mountains. Of course, you are missing a couple big gears on top so on the flats or the downhills you will run out of room very quickly. There's not "get" without a "give" in this game. I'm not a triple guy, there are other options you cen go to without having the additional weight and complexity of a triple set up.

Option 1: go with a compact crank set - 34/50. Compact sets will give you the low end you are looking for, but you will sacrifice some of the top end.

Option 2: go with a triple - 30/39/52. This gives you both the low end and keeps most of the top end. However, most folks wont go this way. An extra shift up front can be a pain and they are heavier and more expensive. Once you have one, it's very hard to go to double because it requires new cranks and front shifter, possibly a new chain. Finally the difference in chain lengths just doesn't warrant it.

Option 3: go with a standard 53/39 crank in the front and get a couple different cassettes for the rear. This is what I did. I am using a Campy setup and have a standard 12-25 for riding around home and a 13-29 for the mountains - using a medium rear derailleur. Shimano doesn't have a 13-29, which is the big reason I'm riding Campy now. I can easily swap cassettes without having to do anything to the chain or derailleur.

Good luck with this one. If you live in an area with roads of less than say 8 percent grades, the double will be just fine. Of course, it's up to you. Work with your local bike shop. They should let you test drive one of each. This is the best way to figure it out.
 

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Discussion Starter · #5 ·
yeah Thanks for the write-up I tested both the double and the triple and I felt good with the double and there are no mountains around here and not many hills so I would go with the double for sure and maybe upgrade to a compact set sometime if I get really into it.
 

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JWMGT90 said:
no whats the purpose of 2 or 3 chainrings?
Generally speaking, a triple crank will give you a larger number of gear ratios, particularly in the lower end and in the middle. A standard double crankset will have a 53 tooth ring and a 39 tooth ring. A triple will have a third chainring that is smaller than the 39 tooth ring, usually a 30 tooth ring. If you live in a mountain range and are not in great shape you probably need a triple crank, but it is often not necessary. If you are concerned about making it up steep hills, a compact crank (a double with slightly smaller chainrings) is a good idea.
 

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a few thoughts...

The purpose of a compact or triple is too add more lower gear ratios.

There have been a few mistakes in previous postings. A triple crank bike may have exactly the same big chainring and middle chainring as a double crank, like 53/39, so there is NO loss of top gear. The third ring is most often a 30T, that adds three additional lower gear ratios. It could be setup to have MORE top gear and still have three more lower gears. I rode a 53/39/28 with a 12-25 cassette for years in the mountains. I could have used an 11-23 for more top gear and still had a low gear that was equivalent to a 39/32 or 34/28.

A compact is often the safest bet for beginner. A 50/34 with an 11-25 cassette will produce slightly more top gear than a 53/12 and a low that's close to a 39/29. The only penalty is more cog shifting to make up for the big jump after shifting between the chainrings. It will always require one more cog-shift than a 53/39, but it doesn;t take long to get used to.

With no information on your physical shape, no one can say that you can get by without the lower gears of a triple or compact. That's total speculation. It's probably true if you're athletic or the terrain you ride has few hills. If you't got mountains to deal with that's another story.
 

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Shimano road can run up to a 30 tooth cassette

BizkitShooter said:
Shimano doesn't have a 13-29, which is the big reason I'm riding Campy now. I can easily swap cassettes without having to do anything to the chain or derailleur.
Shimano doesn't make beyond a 12-27 road cassette BUT SRAM makes an 11-28 and IRD makes both 11-28 and 11-30 (they also make 11-32, 11-34, and 12-34 ten speed casettes). Shimano says their road short cage dérailleurs are limited to a maximum 27 tooth cog...but I have personally run them on up to 30 tooth large cogs with zero issues on a double crankset.

So you could go double (standard or compact) with still having a nice low gear. You can go even lower using a MTB mid-cage rear dérailleur (using the IRD cassettes).

:thumbsup:
 
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