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Discussion Starter · #1 ·
I like to go lower gears ratio (or add additional lower gears - optional) to my current set-up for hilly terrain. I don't mind losing a bit of the top end gear ratio.
What will be the cheaper way to do it without going Compact or Triple Crankset?

My current Set-up: -

Crankset - Double 52/39 (Shimano 105)
cassette - 12/27
Rear derailleur - Short Cage (Shimano Ultegra)
Front derailleur - Shimano 105

Or changing to Compact crankset and the rest remain the same will be the cheaper options?
Appreciate the advice.
 

· Los Barriles, BCS, Mexico
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nizee said:
I like to go lower gears ratio (or add additional lower gears - optional) to my current set-up for hilly terrain. I don't mind losing a bit of the top end gear ratio.
What will be the cheaper way to do it without going Compact or Triple Crankset?

My current Set-up: -

Crankset - Double 52/39 (Shimano 105)
cassette - 12/27
Rear derailleur - Short Cage (Shimano Ultegra)
Front derailleur - Shimano 105

Or changing to Compact crankset and the rest remain the same will be the cheaper options?
Appreciate the advice.
To go to a triple, you would have to buy the crankset, bottom bracket and front dérailleur. Another way to achieve what you want that is worth looking into is to replace your rear derailleur and cassette with a Shimano XT MTB long cage dérailleur and 12/34 cassette.
 

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Depends on how low you want to go.

The easiest and cheapest would be to run an IRD cassette. They make a 12-30t model that will work with a road short cage derailleur. It's not the cage length that makes a mountain derailleur work with the really big cassettes, it's the actuation angle of the knuckles. A road derailleur will throw the upper pulley into the 32 or 34t cogs no matter how you adjust it. The reason mountain bikes and anything with a triple runs the long cage is to take up slack in the chain when you are in the small ring up front. You need to have more chain when the tooth difference is so great form the granny to the big ring.

If you can find a deal on a Shimano or FSA alloy compact, then you wouldn't even have to switch BB's. Just lower your front derailleur and go. You might also appreciate the tighter ratios you'd keep in back by switching out just the crankset.

The next step would be the combo of the two. It would get you a pretty low gear and a really wide range. It would be worth playing around on Sheldon's site to check out the gear ratios to make certain you aren't doubling up too many of the gear inch combos.

A mountain cassette and derailleur would be next. Just be aware that you'll have some pretty big jumps in gears, especially when you are at the big end of the cassette. Don't worry about mountain stuff being 9sp and road being 10. It will work just fine.

Triple is next due to all of the expense of switching the bits. We're talking BB, Crank, front derailleur, shifter and chain. Before you do all of that, I'd look at the gear charts and see how far you actually need to go.

Last is the triple front with the mountain combo in the back. Pretty much overkill for everything except loaded touring and climbing trees.

One last thing. Is this for a cross bike that will be raced? Because if you are going so slow to actually be riding a ultra low gear in a race, you are better off running. If it's for a do everything bike, then good luck and have at 'er.
 

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Discussion Starter · #4 · (Edited)
DaveT said:
To go to a triple, you would have to buy the crankset, bottom bracket and front dérailleur. Another way to achieve what you want that is worth looking into is to replace your rear derailleur and cassette with a Shimano XT MTB long cage dérailleur and 12/34 cassette.
thanks for the reply. If i were to do 12/34 MTB cassette and the long cage MTB derailleur, i would also need a new chain and i'll be missing 1 gear-speed, correct?
Will the total price for the above have almost the same as changing to double crankset (Shimano FC-R700 - $220).

Am i right if i change to Shimano FC-R700, i don't have to change the rest?

I was thinking of going 12/28 or 12/30 and change to medium cage, will that works? But who make 12/28 or 12/30 cassette?
 

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Discussion Starter · #5 ·
Unoveloce said:
The easiest and cheapest would be to run an IRD cassette. They make a 12-30t model that will work with a road short cage derailleur. It's not the cage length that makes a mountain derailleur work with the really big cassettes, it's the actuation angle of the knuckles. A road derailleur will throw the upper pulley into the 32 or 34t cogs no matter how you adjust it. The reason mountain bikes and anything with a triple runs the long cage is to take up slack in the chain when you are in the small ring up front. You need to have more chain when the tooth difference is so great form the granny to the big ring.

If you can find a deal on a Shimano or FSA alloy compact, then you wouldn't even have to switch BB's. Just lower your front derailleur and go. You might also appreciate the tighter ratios you'd keep in back by switching out just the crankset.

The next step would be the combo of the two. It would get you a pretty low gear and a really wide range. It would be worth playing around on Sheldon's site to check out the gear ratios to make certain you aren't doubling up too many of the gear inch combos.

A mountain cassette and derailleur would be next. Just be aware that you'll have some pretty big jumps in gears, especially when you are at the big end of the cassette. Don't worry about mountain stuff being 9sp and road being 10. It will work just fine.

Triple is next due to all of the expense of switching the bits. We're talking BB, Crank, front derailleur, shifter and chain. Before you do all of that, I'd look at the gear charts and see how far you actually need to go.

Last is the triple front with the mountain combo in the back. Pretty much overkill for everything except loaded touring and climbing trees.

One last thing. Is this for a cross bike that will be raced? Because if you are going so slow to actually be riding a ultra low gear in a race, you are better off running. If it's for a do everything bike, then good luck and have at 'er.
Thanks for the reply.
It's for roadbike. The terrain will have a few long and short hill climb. With the current set-up, especially during the long hill climb, i find my pedaling getting heavier and heavier with the lowest gears i have towards 3/4 to the end. I like to have lower gear ratio to go down with and to try out and hopefully maintain my cadence.

So, by just purchasing the Shimano FC-R700 Compact Crankset will work with my current bottom bracket and the rest of the components (with corrent chain-length)? I'm using 105 crankset currently.

If this works, then i can re-use back the old crankset for flat terrain and change back to compact for hilly terrain, correct?
 

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Going to the long cage rear derailluer with a 11-34 cassette is probably about the same cost as switching to a compact crank. If you ran a compact crank, your 12-27 should be low enough for most climbs unless you are a really big guy, smoke, or are just plain out of shape. You could then have a 12-25 or even an 11-23 cassette for flatter rides, and with the extra cassette, you would find, I beleive, that you won't ever need the 39/53 again. I'm a big guy [275lbs] I ride in the mtns of western NC and run a 34/50 with a 12-27 and that ratio works for all but the toughest climbs, which I have no business being on at my size anyway.
 

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Discussion Starter · #7 ·
cyclust said:
Going to the long cage rear derailluer with a 11-34 cassette is probably about the same cost as switching to a compact crank. If you ran a compact crank, your 12-27 should be low enough for most climbs unless you are a really big guy, smoke, or are just plain out of shape. You could then have a 12-25 or even an 11-23 cassette for flatter rides, and with the extra cassette, you would find, I beleive, that you won't ever need the 39/53 again. I'm a big guy [275lbs] I ride in the mtns of western NC and run a 34/50 with a 12-27 and that ratio works for all but the toughest climbs, which I have no business being on at my size anyway.
Thanks for the advice cyclust.
So, do i need to change by BB if i change my crankset to Shimano FC-R700 (or Ultegra SL FC-6650-G) from my current 105 crankset?
My current 105 front derailleur will work with the compact crankset, correct? I just have to lower it becauses it's 110mm BCD (from 130mm BCD on my 105).

I need confirmation before i place an order over at performance. They having 20% off.
 

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nizee said:
Thanks for the advice cyclust.
So, do i need to change by BB if i change my crankset to Shimano FC-R700 (or Ultegra SL FC-6650-G) from my current 105 crankset?
My current 105 front derailleur will work with the compact crankset, correct? I just have to lower it becauses it's 110mm BCD (from 130mm BCD on my 105).

I need confirmation before i place an order over at performance. They having 20% off.
You said "cheapest," so why not get the R-600? Even cheaper, R-4550 would work, too. Current FD will work, yes. Check on BB, should work as well.

http://www.jensonusa.com/store/product/CR309B03-Shimano+R600+Compact+Road+Cranksets.aspx

http://www.jensonusa.com/store/product/CR308B07-Shimano+R4550+Cranksets.aspx
 

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Discussion Starter · #10 ·
wim said:
You said "cheapest," so why not get the R-600? Even cheaper, R-4550 would work, too. Current FD will work, yes. Check on BB, should work as well.

http://www.jensonusa.com/store/product/CR309B03-Shimano+R600+Compact+Road+Cranksets.aspx

http://www.jensonusa.com/store/product/CR308B07-Shimano+R4550+Cranksets.aspx
Wow, thanks....good find.
I just notice i can get $180-20%=$144plus tax with free shipping to store for the R700.

What are the differences between the R700 and R600, apart from R600 being the older model?
 

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DaveT said:
Another way to achieve what you want that is worth looking into is to replace your rear derailleur and cassette with a Shimano XT MTB long cage dérailleur and 12/34 cassette.
If the current shifters are 10-speed a Shimano mountain cassette won't work because they are 9-speed. There are a few aftermarket 10-speed mountain cassettes available that would work with a Shimano mountain rear derailleur. But the downside of any mountain cassette is that the bigger ratio jumps from cog to cog cause bigger cadence jumps. On flatter rides there will often be times that one cog is too small and the next is too big.

Al
 

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nizee said:
Wow, thanks....good find.
I just notice i can get $180-20%=$144plus tax with free shipping to store for the R700.

What are the differences between the R700 and R600, apart from R600 being the older model?
Do you have 105 9spd or 10spd?

The R600 is not quite as nice as 105 10spd. It has groove on the backside of the arm and is a bit heavier. The R700 is Hollowtech and is closed up on the back. I would rate it as 1/2 way between 105 and Ultegra in quality and finish.

The other option is the 105 Compact Crank the FC-5650. Pops right in and would go with your existing components. (If you're into that kind of thing...)
 

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since your current crank is a double 105 crank, you can use the same BB. Assuming it is the outboard bearing 10 speed crank with the spindle being attached to the drive side crank arm] Current frt derailleur will work also.You will probablt need to remove, say 2 links from your chain. This set up will work fiine with your short cage rear derailleur, though I have switched my rear from a Dura ace short cage to a Ultegra long cage, as I run the 12-27 cassette, and it has improved shifting performance. A comkpact crank combined witha 12-27 cassette maxes out the capactiy of a short cage RD, and though it will work, mine now works better with the increased capacity oif the long cage. Just something to keep in mind. Good luck, send me a personnal message if you need any further help.
 
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