Difference between Ultegra fc-6800 and fc-6850 chainset?
luv2ride
Posts: 2,367
https://www.probikekit.co.uk/bicycle-cr ... 91323.html
Thinking of upgrading my non-series Shimano chainset to an Ultegra r8000. Was initially avoiding the 6800 series due to reading about crankset failures. Came across this 6850 version. Anyone know how it might differ from the 6800?
Cheers
Thinking of upgrading my non-series Shimano chainset to an Ultegra r8000. Was initially avoiding the 6800 series due to reading about crankset failures. Came across this 6850 version. Anyone know how it might differ from the 6800?
Cheers
Titus Silk Road Ti rigid 29er - Scott Solace 10 disc - Kinesis Crosslight Pro6 disc - Scott CR1 SL - Pinnacle Arkose X 650b - Pinnacle Arkose singlespeed - Specialized Singlecross...& an Ernie Ball Musicman Stingray 4 string...
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Comments
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6850 denotes a compact chainset of 50/34 although all the 6800 series appear to have a 110mm bcd.0
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6850 is optimised for Di2
6800 is also available as a compact
https://m.bikester.co.uk/shimano-ultegr ... 12155926:s0 -
BikerGroveish wrote:6850 is optimised for Di2
6850 is not 'optimised' for Di2. 6870 series is Di2.0 -
Imposter wrote:BikerGroveish wrote:6850 is optimised for Di2
6850 is not 'optimised' for Di2. 6870 series is Di2.
You’re wrong. 6870 is the hydraulic disc brake Di2 Groupset and 6850 the rim braked Di2 groupset. Not that that effects the chainset greatly or at all.0 -
If you do upgrade to Ultegra 8000 check it works with your front derailleur. The r8000 crankset has slightly different spacing. According to Shimano it’s not backwards compatible but you may get away with it.0
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BikerGroveish wrote:Imposter wrote:BikerGroveish wrote:6850 is optimised for Di2
6850 is not 'optimised' for Di2. 6870 series is Di2.
You’re wrong. 6870 is the hydraulic disc brake Di2 Groupset and 6850 the rim braked Di2 groupset. Not that that effects the chainset greatly or at all.
You are wrong and imposter is right.
6870 is rim brake Di2. I don't think the 6800 hydro groupset has its own designation.
Only the 8000 series has the differentiation.
6850 means compact, although as stated, all the new, 4-arm chainsets across the Shimano range are fully cross compatible with all chainring sizes as they all have the same BCD.0 -
barongreenback wrote:If you do upgrade to Ultegra 8000 check it works with your front derailleur. The r8000 crankset has slightly different spacing. According to Shimano it’s not backwards compatible but you may get away with it.
That’s good to know. The R8000 is a nicer looking chainset.0 -
Shirley Basso wrote:BikerGroveish wrote:Imposter wrote:BikerGroveish wrote:6850 is optimised for Di2
6850 is not 'optimised' for Di2. 6870 series is Di2.
You’re wrong. 6870 is the hydraulic disc brake Di2 Groupset and 6850 the rim braked Di2 groupset. Not that that effects the chainset greatly or at all.
You are wrong and imposter is right.
6870 is rim brake Di2. I don't think the 6800 hydro groupset has its own designation.
Only the 8000 series has the differentiation.
6850 means compact, although as stated, all the new, 4-arm chainsets across the Shimano range are fully cross compatible with all chainring sizes as they all have the same BCD.
You’re wrong There is a 6800 compact as I pointed out.0 -
BikerGroveish wrote:Imposter wrote:BikerGroveish wrote:6850 is optimised for Di2
6850 is not 'optimised' for Di2. 6870 series is Di2.
You’re wrong. 6870 is the hydraulic disc brake Di2 Groupset and 6850 the rim braked Di2 groupset. Not that that effects the chainset greatly or at all.
6850 is not Di2 - 6870 is Di2. Furthermore, 6870 is not disc-specific as you imply. I'm beginning to wonder if you are some kind of troll account. All over these forums, I see you posting inaccurate bollox and this is yet another example.0 -
Imposter wrote:BikerGroveish wrote:Imposter wrote:BikerGroveish wrote:6850 is optimised for Di2
6850 is not 'optimised' for Di2. 6870 series is Di2.
You’re wrong. 6870 is the hydraulic disc brake Di2 Groupset and 6850 the rim braked Di2 groupset. Not that that effects the chainset greatly or at all.
6850 is not Di2 - 6870 is Di2. Furthermore, 6870 is not disc-specific as you imply. I'm beginning to wonder if you are some kind of troll account. All over these forums, I see you posting inaccurate bollox and this is yet another example.
Why don’t you shut up you obviously have no clue what you’re going on about. You’re a crow. That’s someone who hangs around on a subject specific forum with no knowledge or experience of the subject. Do yourself a favour and do one.0 -
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Indeed.Shirley Basso wrote:6850 means compact, although as stated, all the new, 4-arm chainsets across the Shimano range are fully cross compatible with all chainring sizes as they all have the same BCD.
For those that don't know before the advent of compact chainsets Shimano had for several years tended to use a bcd of 130mm on its upper ranges of road chainset. When compact chainsets came along they had to introduce a new 110mm bcd spider and added the 50 to the series number to differentiate between standard and compact sizes.
When they realised compacts weren't going to go away Shimano decided that instead of making two different spider sizes it would be more economical to make one size fits all so all subsequent road series use a 110mm bcd and the need for adding the 50 to the series number became obsolete.
However, this has not stopped companies using the 50 to differentiate compact ratio chainsets. In the link luv2ride provided the 6850 is a compact chainset whilst PBK also sell the 6800 chainset with standard rings yet both use the same 6800 110mm spider.0 -
BikerGroveish wrote:https://www.cyclingweekly.com/reviews/gears-drivetrain/shimano-ultegra-groupsets
As you can see you’re wrong again.
That link simply confirms what myself and shirley said earlier is correct. Is this a wind-up or is there actually something wrong with you?0 -
Imposter wrote:BikerGroveish wrote:https://www.cyclingweekly.com/reviews/gears-drivetrain/shimano-ultegra-groupsets
As you can see you’re wrong again.
That link simply confirms what myself and shirley said earlier is correct. Is this a wind-up or is there actually something wrong with you?
https://www.cyclingweekly.com/news/prod ... disc-240670 -
BikerGroveish wrote:Imposter wrote:BikerGroveish wrote:https://www.cyclingweekly.com/reviews/gears-drivetrain/shimano-ultegra-groupsets
As you can see you’re wrong again.
That link simply confirms what myself and shirley said earlier is correct. Is this a wind-up or is there actually something wrong with you?
https://www.cyclingweekly.com/news/prod ... disc-24067
..and the disc kit featured there is the non-series Shimano kit mentioned earlier. Give it a rest mate, you're embarrassing yourself...0 -
Imposter wrote:BikerGroveish wrote:Imposter wrote:BikerGroveish wrote:https://www.cyclingweekly.com/reviews/gears-drivetrain/shimano-ultegra-groupsets
As you can see you’re wrong again.
That link simply confirms what myself and shirley said earlier is correct. Is this a wind-up or is there actually something wrong with you?
https://www.cyclingweekly.com/news/prod ... disc-24067
..and the disc kit featured there is the non-series Shimano kit mentioned earlier. Give it a rest mate, you're embarrassing yourself...
What are you smoking?
It’s the 6870 Di2 disc groupset.0 -
BikerGroveish wrote:Imposter wrote:BikerGroveish wrote:Imposter wrote:BikerGroveish wrote:https://www.cyclingweekly.com/reviews/gears-drivetrain/shimano-ultegra-groupsets
As you can see you’re wrong again.
That link simply confirms what myself and shirley said earlier is correct. Is this a wind-up or is there actually something wrong with you?
https://www.cyclingweekly.com/news/prod ... disc-24067
..and the disc kit featured there is the non-series Shimano kit mentioned earlier. Give it a rest mate, you're embarrassing yourself...
What are you smoking?
It’s the 6870 Di2 disc groupset.
There is no 6870 'disc' groupset. You can find 6870 hydro disc groupsets for sale, but they all use the ST R785 non-series levers. You only have to look at the pics in the links you provided to see that. It would be far easier for you just to accept that you are wrong, or trolling, or something.
Fundamentally though - what you said about 6850 being Di2 is simply not correct. Not sure how we got onto the hydro stuff..0 -
Yea but 6850 doenst specifically refer to rim, disc or anything. Just that the chainset itself is a compact.
6870 makes no reference to disc brake. It's just the di2 version of 6800.
You comment :
"You’re wrong. 6870 is the hydraulic disc brake Di2 Groupset and 6850 the rim braked Di2 groupset. Not that that effects the chainset greatly or at all."
Is incorrect. 6870 is the di2 version of 6800. Nothing more (although I'd say it actually refers to rim brake more specifically than disc but I'm not that fussed)0 -
I bet the OP wishes he'd never asked...0
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Stick with the non series Chainset. Upgrading will made no real noticeable difference. I am building a bike up using my old 6800 Groupset. As I had no ultegra Chainset I’ve simply bought a cheap RS500 for £45 off Merlin saving over £100 against the Ultegra.0
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It depends on your motivation for changing the chainset.
If it's weight saving, any Ultegra will be lighter than your non-series chainset. (And don't worry about reports of crank failures; the internet just makes it easy to find the few isolated cases. If there was a widespread issue we'd have seen a safety recall at least in the USA)
If it's for looks, get the R8000 otherwise you'll be wishing you'd done so in a few months time.
If it's for practical reasons, ie the existing one's got worn out chainrings or you want to move from a standard to compact, just get the cheapest one you can find.0 -
I wondered myself. I bought two bikes one with a compact and one with a non compact crankset and I am swapping them. The non-compact is only 20grams heavier (737g vs 715g and 52/39 vs 50/34 both with in 170mm arms).
The only drawback of the non compact one for me is the nasty plastic tightening nut. I often replace them with aluminium ones bought from China that can be tightened with a 10mm Allen key rather than that giant T tool which I have in plastic only and the teeth wear out. I had to remove the top of the tool with a grinder to undo the non-compact crankset. The compact crankset has nicer (but still T star thing) aluminium nut. I think that the compact crank in gun metal colour with a larger "Ultegra" branding, may be a later version though the numbers are still FC-6850 and FC-6800 for compact and non compact respectively. I like to think that having a larger BCD means that there is less chance that the chainrings will flex though it is possible to purchase non compact chainrings for the smaller 110 BCD cranks. I have gone off using the modern Shimano four arm 110BCD chain rings with their fancy hollow design because they too expensive for a part that wears out.
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