I have entered a really hilly triathlon and will need some lower gears. I currently have a double ultegra chainset (hollotech 2). I am not sure of the exact cassette and rings i have but assume the block is 11-25 and rings 39-50. I dont think i can just put another ring on my double crankset so need to find a way of getting more gears.

Firstly, will my front shifter work with a triple chainset? If not then i am guessing the best i can achieve is putting a 12-27 block on the back and new chain? Or can you get smaller than a 39 tooth middle ring?

Would i be better off buying a new drive side crank that i can put another ring on? Anyone know where i can get just the crank/spider/axle for the drive side?

Lastly, I have an LX mountain bike chainset, can i just move my road rings on to that and put it in my road bike? Or will the rings not fit a mtb spider and will i be stuck with the 22-32-44 mtb rings? Are the crank arm lengths about the same?

Any help would be appreciated.

Thanks,
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I have entered a really hilly triathlon and will need some lower gears. I currently have a double ultegra chainset (hollotech 2). I am not sure of the exact cassette and rings i have but assume the block is 11-25 and rings 39-50. I dont think i can just put another ring on my double crankset so need to find a way of getting more gears.

Your crankset is most likely a 39/52 or 53 tooth. You're right, you can't just add a 3rd chainring to a double crank.

Firstly, will my front shifter work with a triple chainset? If not then i am guessing the best i can achieve is putting a 12-27 block on the back and new chain? Or can you get smaller than a 39 tooth middle ring?

Your front shifter might work with a triple chainring, we'd need more info as to what front shifter you have. You can put a 12-27 tooth cassette on, that will give you a slightly lower gear. You can put a 38 tooth ring on a crank with a 130mm BCD...that's the smallest that will fit.


Would i be better off buying a new drive side crank that i can put another ring on? Anyone know where i can get just the crank/spider/axle for the drive side?

I don't think this is a feaseable plan. Chainlines will be off if you put a triple driveside cranks on the BB that's designed for the double that you have now.

Lastly, I have an LX mountain bike chainset, can i just move my road rings on to that and put it in my road bike? Or will the rings not fit a mtb spider and will i be stuck with the 22-32-44 mtb rings? Are the crank arm lengths about the same?

Nope, the BCDs are different and the number of arms carrying the crankarms might be different as well. The LX probably only has 4 arms and the road crank has 5 arms. If you put the LX cranks on your road bike, you'll be stuck with the 22-32-44 rings that are in that cranks. Crank arm lengths might be the same...I ride the same length on both my road bike and my MTBs.

Any help would be appreciated.

Thanks,
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I think your best bet is to buy a compact road double crankset. Something like a 34/50 tooth set up...this is most likely to work with the rest of the equipment that you already have.

+1 the compact route, that will be the easiest, and if you put a 12-27 in the rear you'll have stump pulling power to spare!

"I have entered a really hilly triathlon and will need some lower gears. I currently have a double ultegra chainset (hollotech 2). I am not sure of the exact cassette and rings i have but assume the block is 11-25 and rings 39-50. I dont think i can just put another ring on my double crankset so need to find a way of getting more gears."

Don't assume. The number of teeth is stamped into the rings, right side of big ring, left side of other(s) if Shimano.

"Firstly, will my front shifter work with a triple chainset? If not then i am guessing the best i can achieve is putting a 12-27 block on the back and new chain? Or can you get smaller than a 39 tooth middle ring?"

If 10-speed, NO, if 9-speed, YES. The smallest chainring that will fit a Shimano double is a 38.

"Would i be better off buying a new drive side crank that i can put another ring on? Anyone know where i can get just the crank/spider/axle for the drive side?"

To convert to a triple you will need a new triple crankset, bottom bracket, front and rear derailleurs, and new left shifter if 10-speed. This conversion will probably give you the best results.

"Lastly, I have an LX mountain bike chainset, can i just move my road rings on to that and put it in my road bike? Or will the rings not fit a mtb spider and will i be stuck with the 22-32-44 mtb rings? Are the crank arm lengths about the same?"

No, your Ultegra crankset has a 130 BCD, it will not accept mountain chainrings. You could put the LX crankset on the roadbike but the front derailleur will probably not work with it. It is difficult and tricky to convert a roadbike to run well with a mountain crankset and if you have a braze-on front derailleur it's next to impossible because the derailleur won't go low enough. Also a road derailleur is designed to work with larger chainrings and a road shifter. A mountain derailleur has a different throw ratio than a road derailleur.

If 9-speed, you could replace the rear derailleur with a mountain RD and the cassette with a mountain cassette, 12-32 or 12-34. If 10-speed you could use a mountain RD and an aftermarket 10-speed mountain cassette. This would be a relatively cheap conversion but the downside is the big ratio jumps when shifting from cog to cog.

A compact crankset may be a good alternative. Personally I don't think I would like the typical 50/34 chainrings because of the big ratio jumps, a 50-36 would fit my needs better.

Al

With a compact chainset would i be able to stick my current outer ring on it and keep the big ring for going back down the hill?

Another question, i have found a nice and cheap tiagra compact chainset. The shimano website says its 9 speed compatible. I have a 10spd rear cassette. Will this not work?

Thanks,
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With a compact chainset would i be able to stick my current outer ring on it and keep the big ring for going back down the hill?

Nope, they will have different BCDs.

Another question, i have found a nice and cheap tiagra compact chainset. The shimano website says its 9 speed compatible. I have a 10spd rear cassette. Will this not work?

Thanks,
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As far as I know, Shimano does not give names to their compact cranks. If it's a Tiagra, it might not be compact. They do have a crank that is Tiagra level that is compact and is 9 speed compatible. If this is the one you found, it should work fine with 10 speed stuff.

This is what i found.

http://cycle.shimano-eu.com/catalog/cycle/products/component.jsp?PRODUCT%3C%3Eprd_id=845524441784203&FOLDER%3C%3Efolder_id=2534374302050298&ASSORTMENT%3C%3East_id=1408474395181667&bmUID=1179248310372

Really appreciate the advice guys.

Adam

If this is just a one time deal you might want to just go with a 12-27 cassette. I don't know what "Hilly Triathlon" you are doing, we have one coming up in my area, the Auburn Triathlon where you climb Iowa Hill Road. They recommend at least a 12-27 or a triple. I've done it with a 12-25 but it was very difficult. A 12-27 would have worked better. If you do a lot of climbing in general you could go to a compact crank, but if it's just for one ride, it would be expensive. If you don't do a lot of climbing in general and have not trained for hills, no matter what you do it will still be hard...good luck!

This is what i found.

http://cycle.shimano-eu.com/catalog/cycle/products/component.jsp?PRODUCT%3C%3Eprd_id=845524441784203&FOLDER%3C%3Efolder_id=2534374302050298&ASSORTMENT%3C%3East_id=1408474395181667&bmUID=1179248310372

Really appreciate the advice guys.

Adam

That should work just fine. If you want to go to a compact crankset, I don't think you need to worry about losing any top end speed. There are lots of threads here about the very small difference in top gear when dropping from a 52 or 53 tooth big ring down to a 50 tooth ring on a compact crankset. You probably won't spin out either gear on most downhills.

Cheapest way that's guaranteed to work decently? New cassette. You probably don't even have to change the chain, as long as you're careful not to shift into the big-big combo.

if a 12-27 isn't enough, IRD does make their 11-28 in a shimano 10 speed version.

This is the cheapest (free) solution if you have 9 spd mountain bike cassette and derailleur available to try.

http://www.bikeforums.net/showthread.php?t=288448

Use a 11-34 cassette with the long cage RD. Nothing up front changes as in crankset or shifters. It is a Shimano mountain bike cassette and RD, and will climb anything. Still have the 53/11 combo for the downwind flats and descending. The gaps between gears are obviously bigger, but for a ride with serious climbs, I believe the mission is the get to the top of the mountain.

I agree with the 3 or so posts regarding mtb or long cage derailleurs. They work with shimano road sti levers and they accomodate salad-plate-size cassetes, 34 or whatever. Some cyclocorss riders use this setup. You could also use a 38 chainring but thats a small difference compared to your 39,

I agree with the 3 or so posts regarding mtb or long cage derailleurs. They work with shimano road sti levers and they accomodate salad-plate-size cassetes, 34 or whatever. Some cyclocorss riders use this setup. You could also use a 38 chainring but thats a small difference compared to your 39,

He said he has a 10-speed. A 9-speed cassette is not compatible. Shimano does not make 10-speed mountain bike cassettes.