Alternative for Ultegra Triple Chainset?

[mnichols]

Hi, I'm looking for an alternative for a 10 speed Ultegra Chainset, specifically I want a lower inner ring than the current 30 maybe 26? I would like to keep the outer the same, and the middle is fine, but happy to change if I need to.

I don't want to change the cassette, rear mech or shifters but if I have to change the front mech that's fine. Currently everything is Ultegra.

I don't want to increase the weight of the setup.

Whilst I haven't found a hill that I can't get up on with the current setup I do have to drop my cadence on anything over about 15%, and having done a lot of work on my power zones over winter I know that I put out a lot less watts when I do this. Also, it's a lot harder on my knees and more tiring on longer rides and tours especially when carrying luggage

I know I could put a longer mech on the back and increase the cassette, but I like the Ultegra rear mech and find it very slick. In my experience bigger cassettes have too big a range and get a bit 'slappy'. I think I'm on an 11 -28 at the moment

[Brucey]

there were such things as you require eg FC6603

http://www.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/FC/EV-FC-6603-2366E_v1_m56577569830621036.pdf

but I think they are all sold out now. You may still find FC5603 which also has a 74mm inner ring mounting.

Anyway it is so much easier to fit a cassette with a larger sprocket, and I think your rear mech will allow that, so I know what I'd do....

cheers

[531colin]

Perhaps i'm misunderstanding.
Isn't it 130/74 BCD? Can't you just bolt an inner ring less than 30T onto the existing chainset? (stuck with the 39T middle ring, thats the smallest will go on a 130 spider.. F. mechs. could cope with this in the past, maybe current ones can't?)

[keyboardmonkey]

I read somewhere that the 6703 chainset does not allow a chainring smaller than a 30T to be fitted. I also read that some people dropped down a level and bought the Shimano 105 triple for just that reason. It's not a cheap solution, but my understanding is that the 5703 chainset will allow a smaller inner to be fitted. Here's just one example that seems to confirm it:

http://www.bikeforums.net/bicycle-mecha ... -best.html

Of course you would lose that 52 outer (!) chainring - assuming you have a 6703 chainset - but with an 11-28 cassette the gearing Is still fairly high at the top end, IMHO. And a 6700 12-30 cassette will give you fair range of gears will relatively modest jumps between them.

[UpWrong]

Modern 10 speed Shimano triples are not 130/74 bcd. The inner ring is attached to the middle ring rather than bolted to the spider. It saves a bit of weight but you can't have a smaller inner ring. EDIT: It's 92 bcd on my Tiagra 4603 crankset. Not sure if this is universal on Shimano road triples though. A 105 5703 triple is reported to have a 74 bcd inner.

[keyboardmonkey]

Modern 10 speed Shimano triples are not 130/74 bcd. The inner ring is attached to the middle ring rather than bolted to the spider. It saves a bit of weight but you can't have a smaller inner ring.

It depends what you mean by "modern 10 speed [road] triples", I suppose. Shimano, of course, currently offer just Tiagra 4703 as a road triple option across its entire current range, but...

viewtopic.php?f=5&t=48307&p=401223&hilit=5703+ultegra+triple#p401223

[mnichols]

I'm not wedded to keeping the Ultegra Chainset I don't mind changing the whole thing out as it's probably done 20,000 miles and is quite scruffy also I prefer the look of some of the old school chainrings

According to the lbs I'm as low as I can go on the cassette without changing the mech....I thought that was 28 but maybe I'm lower

[Chat Noir]

I have Ultegra triple on my Bob Jackson, currently 52/39/30. I'm planning to fit a 28 to the front (the model I have is 130/74 BCD) to lower it a little. Have also recently invested in a 32 cassette (Ultegra doesn't go this low in 10 speed, I do have the medium derailleur) and figure this will give me a lower gear, if I need to (am doing a Pyrenean Raid in June).

Also have a 105 triple on another bike. If I'm honest it works much more smoothly than the Ultegra.

[whoof]

I think that this has an inner ring with a 74 BCD so you could fit it with say a replacement 26 tooth chainring. £50


http://www.paulmilnescycles.com/shimano ... 3557-p.asp

[meic]

I dont know if these will fit but theoretically they should.
http://www.spacycles.co.uk/m2b0s149p114 ... aptor-ring

[Keezx]

Will not directly fit on double cranksets because of the protrusion near the boltholes on the inner side.
Some grinding/filing might solve this.
I own a different brand with 135/74 BCD and this one has holes near the boltholes to accept the protrusions.

[meic]

In this case it will be going on a triple.
I havent even seen a picture of these new "D type" cranksets from the inside.

I have a suspicion that they may be identical to a double with a slightly longer axle but that is pure speculation.

[mnichols]

On Page 60 of the latest edition of Cycle magazine they have a picture of a triple.....I think that looks great, much nicer than my Ultegra. It also looks modular, i.e., I could put together whatever I want. I'm not technical enough to do it, and I'm not sure my LBS are either...I keep hinting at it. I'm going to take in the picture, otherwise who could put together something like that for me, that would fit my current setup and what sort of money would I be looking at?

[Brucey]

I'm not wedded to keeping the Ultegra Chainset I don't mind changing the whole thing out as it's probably done 20,000 miles and is quite scruffy also I prefer the look of some of the old school chainrings

According to the lbs I'm as low as I can go on the cassette without changing the mech....I thought that was 28 but maybe I'm lower

if you have RD-6700 then your LBS is correct; 28T is the largest recommended sprocket.

http://bike.shimano.com/media/techdocs/content/cycle/SI/RD/SI_5X90A_002/SI_5X90A_001/SI-5X90A-001-ENG_v1_m56577569830671285.pdf

However that hasn't stopped people from fitting a 30T sprocket and having it work; whether this does or not depends on the length of the gear hanger etc.

BTW you may yet decide that you need a long arm mech in order to have enough total capacity. IME it is a bit dodgy to have a setup where the chain runs slack in small-small (but I've done that quite happily) and it is a very bad idea to have a setup where you can't use the big-big combination.

cheers

[The utility cyclist]

I'm not wedded to keeping the Ultegra Chainset I don't mind changing the whole thing out as it's probably done 20,000 miles and is quite scruffy also I prefer the look of some of the old school chainrings

According to the lbs I'm as low as I can go on the cassette without changing the mech....I thought that was 28 but maybe I'm lower

if you have RD-6700 then your LBS is correct; 28T is the largest recommended sprocket.

http://bike.shimano.com/media/techdocs/content/cycle/SI/RD/SI_5X90A_002/SI_5X90A_001/SI-5X90A-001-ENG_v1_m56577569830671285.pdf

However that hasn't stopped people from fitting a 30T sprocket and having it work; whether this does or not depends on the length of the gear hanger etc.

BTW you may yet decide that you need a long arm mech in order to have enough total capacity. IME it is a bit dodgy to have a setup where the chain runs slack in small-small (but I've done that quite happily) and it is a very bad idea to have a setup where you can't use the big-big combination.

cheers

Sorry but that is incorrect, the largest toothed sprocket that can be used as recommended by Shimano is 30T, in fact you can use a 6700 with a 32T sprocket without any bother and that applies to both short cage and GS model, obviously the latter has more capacity. Shimano even made a 12-30 Ultegra '6700' 10 speed cassette.

Unless you're a serial cross chainer then you can run an SS with a triple, it's not for everyone obviously, however people who continually run big big just want a slap as far as I'm concerned, just why, what possible purpose does it serve?