# What chainring combination are possible with the Ultegra 6800 11-speed system?



## Hard Rain (Jan 29, 2010)

I am building a new CX bike for gravel grinding and occasional road/gravel touring. While I could go with a 10-speed triple setup (e.g. the Shimano Ultegra 6703 system), I am intrigued with the new Shimano Ultegra 6800 system. FYI, my frame for this bike will be a custom Ti frame with Salsa Vaya geometry. I will also use a tubular wheel setup (e.g. Hope hubs, Stan's Iron Cross rims, Stan's Ravens 700c x 35mm tires).

For the bulk of my riding (unloaded gravel grinders), I am thinking of using a 36t/46t cyclocross chainrings paired with an 11-28t cassette. This should give me ample top and bottom ends for wind and hills of Kansas (e.g. the Flint Hills). This could also be paired with the long cage Ultegra RD 6800 rear derailleur that would give me the option of running an 11-32t cassette as well.

But for touring (rails to trails rides; perhaps some mountain fire roads) I am exploring what options I have. For their 6800 Ultegra system Shimano makes chainrings as small as 34t and cassettes as wide as 11-32t. Does anyone know if I can pair the 34t chainring with the 46t outer ring (the standard Shimano setup for this smaller inner chainring is 50t/34t compact)? Another/additional option is to use a Shram's mountain 11-speed cassettes (e.g. 12-42t; Shram XG 1195). In either case, I might be forced to use a mountain rear derailleur (e.g. the Shram XO) to handle the rear derailleur capacity).

If you have comments, please chime in.


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## Hard Rain (Jan 29, 2010)

I just called Shimano. For the Ultegra 6800 crankset, there are four chainring options: 46-36T, 50-34T, 52-36T, and 53-39T. All combinations will fit on the same set of crankarms. While other combinations (e.g. 46-34T) might fit, they won't shift as well. However, with the wide range of available cassettes (11-23, 11-25, 11-28, 11-32, 12-25), the 6800 drivetrain provides a wide choice of gearing options by just changing chainrings and/or cassettes.


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## miatagal96 (Jul 5, 2005)

Thanks for the update. It looks like you are going for a double in front - that would be my suggestion. I just switched from a triple to an Ultegra 6800 drive train on my road bike. My triple (105/ultegra combo with FSA crank) was problematic for 7 years. I had several techs say that they should never have made a triple with a 10-speed.

I am going to look into a 44-34 for my cx bike. I can't remember who makes these chain rings, but they are made to work together. I too was told that changing a 36 to a 34 to make 43-36 won't shift as well. I have a 11-28 in the rear. For gravel grinders, the 50-34 is intriguing, but I mostly use my CX bike for CX and on mountain bike trails.

For your wheels, I was looking at Hope hubs and Stans Iron Cross and ended up with Stans Ti hubs with Iron Cross rims. Dave from Speeddream wheels built them for me and said I wouldn't need the engagement of Hope hubs for CX and recommended I save weight instead. For CX, he was right. You can't get pretty colors, however. I'm not sure what tire pressure you want for gravel grinders, but you can't go above 40 lbs or so (I believe) with the Iron Cross rims. I over-inflated mine (to 50 lbs) to try to get them to seat well and heard a loud 'pop' 5 minutes later when the tire popped off the rim and exploded Stans all over the room. So if you want the option of running higher pressures, I think the Alpha 340's can take higher pressure.


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## Hard Rain (Jan 29, 2010)

miatagal96 said:


> Thanks for the update. It looks like you are going for a double in front - that would be my suggestion. I just switched from a triple to an Ultegra 6800 drive train on my road bike. My triple (105/ultegra combo with FSA crank) was problematic for 7 years. I had several techs say that they should never have made a triple with a 10-speed.
> 
> I am going to look into a 44-34 for my cx bike. I can't remember who makes these chain rings, but they are made to work together. I too was told that changing a 36 to a 34 to make 43-36 won't shift as well. I have a 11-28 in the rear. For gravel grinders, the 50-34 is intriguing, but I mostly use my CX bike for CX and on mountain bike trails.
> 
> For your wheels, I was looking at Hope hubs and Stans Iron Cross and ended up with Stans Ti hubs with Iron Cross rims. Dave from Speeddream wheels built them for me and said I wouldn't need the engagement of Hope hubs for CX and recommended I save weight instead. For CX, he was right. You can't get pretty colors, however. I'm not sure what tire pressure you want for gravel grinders, but you can't go above 40 lbs or so (I believe) with the Iron Cross rims. I over-inflated mine (to 50 lbs) to try to get them to seat well and heard a loud 'pop' 5 minutes later when the tire popped off the rim and exploded Stans all over the room. So if you want the option of running higher pressures, I think the Alpha 340's can take higher pressure.


Yes, I am going with the double up front (Ultegra 6800, 46-36T). Quite frankly, I think that the Ultegra 6800 offers an incredibly wide array of gearing, except perhaps for the loaded touring cyclist but that is not the purpose of my current build. The 50-34T crankset also makes a lot of sense, especially if they provide more cassettes with 12 as the smallest cog.

I too will likely go with the Iron Cross rim, but I may spring for some colored Hope hubs. I have no problem going with very low pressure tires for grinding gravel. I have been riding Stan's Crows at 22-25 PSI for a couple of years now, and I love them.


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## donnieboy (Jan 20, 2014)

Hard Rain said:


> Yes, I am going with the double up front (Ultegra 6800, 46-36T). Quite frankly, I think that the Ultegra 6800 offers an incredibly wide array of gearing, except perhaps for the loaded touring cyclist but that is not the purpose of my current build. The 50-34T crankset also makes a lot of sense, especially if they provide more cassettes with 12 as the smallest cog.
> 
> I too will likely go with the Iron Cross rim, but I may spring for some colored Hope hubs. I have no problem going with very low pressure tires for grinding gravel. I have been riding Stan's Crows at 22-25 PSI for a couple of years now, and I love them.


Shimano Ultegra makes a wonderful touring setup for gravel, so you've made a wise choice and the option to go 32 in rear can help if it's warranted due to steeper climbs and/or weaker legs/knees or serious weight. Generally speaking, I don't think the double 46/36 setup poses any problem for loaded tourers if running 36 teeth in conjunction with 32 in the rear, as it provides a near 1:1 ratio. You'd have to carry ALOT of weight + be in poor health to make that a challenge  I tour and climb gravel with a 38 tooth up front and 28 in the rear with 25 extra pounds of gear including a 2 man tent, inflatable pad, sleeping bag, pants, shorts, shirts, socks, sandles, stove, tinder, knife, lighter, portable saw, gps, map, fishing rod/reel and water/food. But I'm no Olympian because I smoke and do not train in the winter except for short winter cycling commutes on plowed streets with studs. Just my 2 cents of experience in conjunction with shared experience from thousands of cyclists (I work in the industry).

Sounds like you'll have an awesome bike that can support anything your body can throw it's way! Just have fun!


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## Eric Malcolm (Dec 18, 2011)

-A couple of options for you to consider:

TA make chain-wheels for all makes of cranks. I recently got a 47T off Wiggle in the UK. Ribble also sell them (UK as well). TA is an old French specialist manufacturer and make sizes to suit 9-10-11 speed set-ups, Shimano and Campy Compact and 130/135mm webs. 

I have a 53/39 set up that I replaced the 53 with a 47T to make 47/39. The thing to watch out for in the front derailleur is the inner cage. The front side of the cage is high and shaped to follow the outer ring. The inner drops down low, the part to look for is when the derailleur is set to the outer ring, how much clearance is left before it hits the teeth of the inner chainring. On road derailleurs, there is usually not much drop and the gap between chainrings can be close. MTB types drop a lot and are not so tolerant.

Hope this helps.

Eric


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## donnieboy (Jan 20, 2014)

The Shimano Tech docs website could provide an accurate answer to your question. In the drop down menu, just select ultegra and choose the front derailer model you have to see it's max chain ring range. Then (if you know what rings up front and what gears in the back you use), you can enter them into a gear ratio calculator to choose the chainrings you'll actually use to your preferred cadence and terrain. I've found this to be ideal.


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## jrm (Jan 12, 2004)

Im using a 6503 triple converted to a bash/42/30 double with a 11-32 XT cassette. it works..great


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## donnieboy (Jan 20, 2014)

jrm said:


> Im using a 6503 triple converted to a bash/42/30 double with a 11-32 XT cassette. it works..great


Interesting to hear. I guess cassettes are not mutually exclusive in terms of road to road, mtb to mtb. When we talk shifters, the reverse is true.


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## mudge (May 15, 2010)

donnieboy said:


> Interesting to hear. I guess cassettes are not mutually exclusive in terms of road to road, mtb to mtb. When we talk shifters, the reverse is true.


Not entirely true (the shifter bit). Any of the older Shimano shifters that didn't have the cables hidden (like the DA 7700 or 7800, for example) would pair perfectly with any pre-DynaSys Shimano derailleur. The shifters defined the number of gears, not the derailleur, as the cable pull was the same for all shifters. You could pair the 7800 DA shifters with a "9sp" LX, XT, or XTR derailleur and bingo, 10 speeds for your 'cross/gravel bike that could handle a 11x36 cassette. Pair that with a 34t small ring and you could climb a phone pole if you could get traction.


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## vmaxx4 (Jul 13, 2010)

Does anyone offer a single ring narrow/wide option that will fit the 6800 crank?


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## donnieboy (Jan 20, 2014)

vmaxx4 said:


> Does anyone offer a single ring narrow/wide option that will fit the 6800 crank?


Yes


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## trevorrr (Feb 9, 2011)

donnieboy said:


> Yes


I was hoping to get the answer to this question too - couldn't find anything via Google. My cross bike is also my road bike (two wheelsets). I have the 50/34 rings for road, and bought 36/46 rings for cross, but in 6 races I've never used the big ring...


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## donnieboy (Jan 20, 2014)

mudge said:


> Not entirely true (the shifter bit). Any of the older Shimano shifters that didn't have the cables hidden (like the DA 7700 or 7800, for example) would pair perfectly with any pre-DynaSys Shimano derailleur. The shifters defined the number of gears, not the derailleur, as the cable pull was the same for all shifters. You could pair the 7800 DA shifters with a "9sp" LX, XT, or XTR derailleur and bingo, 10 speeds for your 'cross/gravel bike that could handle a 11x36 cassette. Pair that with a 34t small ring and you could climb a phone pole if you could get traction.


It is currently true as of 10 speed and now 11 speed shimano. It is untrue should you go back to 9 speed or less. I'm glad you know that  A step forward to benefit shimano, but a step back for modifications in my opinion. Kinda like using an I phone and being stuck with buying a proprietary charger but they stop making it, so you have to buy a new phone to be able to do what you want.


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## mudge (May 15, 2010)

donnieboy said:


> It is currently true as of 10 speed and now 11 speed shimano. It is untrue should you go back to 9 speed or less. I'm glad you know that


If I understand what you're saying, 9 speed shifters aren't supposed to pair with 8 speed derailleurs, but my experience is quite contrary to that. When Shimano went from 8 to 9 speed, and again from 9 to 10 speed, I bought shifters but didn't buy a new derailleur to make the upgrade to the new standard. Never had a problem, ever, with any shifter/derailleur combo prior to the release of 7900 DA. Granted, I didn't try every conceivable combo, but the ones I tried worked perfectly.


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## donnieboy (Jan 20, 2014)

mudge said:


> If I understand what you're saying, 9 speed shifters aren't supposed to pair with 8 speed derailleurs, but my experience is quite contrary to that. When Shimano went from 8 to 9 speed, and again from 9 to 10 speed, I bought shifters but didn't buy a new derailleur to make the upgrade to the new standard. Never had a problem, ever, with any shifter/derailleur combo prior to the release of 7900 DA. Granted, I didn't try every conceivable combo, but the ones I tried worked perfectly.


Not what I meant. 9 speed or less is cross compatible (between road and mtb) but 10 speed or 11 is not. You already know you can pair a 10 speed derailer to 9 speed shifter and same goes for lower speeds so long as chain is not too wide for jockey wheels, cassette or derailer cages etc (cable pull from shifter determines where the derailer goes - provided derailer and cables are OK), so I won't sing with the choir about cable pull. Hopefully that makes sense to you. I'm a grumpy Shimano certified mechanic with 13 bikes, thousands of custom builds and done with this. Cheers.


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## mudge (May 15, 2010)

donnieboy said:


> Not what I meant. 9 speed or less is cross compatible (between road and mtb) but 10 speed or 11 is not. You already know you can pair a 10 speed derailer to 9 speed shifter and same goes for lower speeds so long as chain is not too wide for jockey wheels, cassette or derailer cages etc (cable pull from shifter determines where the derailer goes - provided derailer and cables are OK), so I won't sing with the choir about cable pull. Hopefully that makes sense to you. I'm a grumpy Shimano certified mechanic with 13 bikes, thousands of custom builds and done with this. Cheers.


Got it. I'm not a grumpy old Shimano mechanic, but I am a cur-mudge-on, so I can appreciate a certain level of frustration with the evolution of Shimano drivetrains and their non-cross compatibility.


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