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Code: GRP-5800B
Shimano's latest 105 groupset, the new 5800 series is now 11 speed with features from the Dura Ace and Ultegra Groupsets.

Shimano's 5800 groupset is the latest in the 105 series of road groupsets. It follows the Dura Ace 9000 and Ultegra 6800 groups in being 11 speed. With a choice of 3 chainset options 34/50, 36/52 and 39/53 together with the 11 speed cassette options there is a 5800 groupset to suit every cyclist.

 

Groupset Contains:

Chainset: FC5800 Choice of 165, 170, 172.5 and 175mm crank lengths, 34/50, 36/52 and 39/53 chainrings. New 4 arm design, 1 design only allows you to interchange chainrings.

Bottom Bracket: BBR60, choice of English or Italian

Cassette: CS5800, choice of 12/25, 11/28 (use SS rear derailleur) or 11/32 (requires GS rear derailleur) 11 speed

Chain: CNHG600 105 11 speed

Rear Derailleur: RD5800 Choice of short cage SS model for use with 11/25 and 11/28 cassette or the GS model with a slighly longer cage for use with the wider ratio 11/32 cassette.

Front Derailleur: FD5800, choice of Braze-On, 31.8 and 34.9 band-on

Brakes: BR561, BR5800 or option for the new 105 R7000 brakes 

STI Brake/Gear Levers: ST5800 Shimano's proven STI levers with concealed brake and gear cables.

Cables: Shimano brake and gear cables (inner and outer) supplied.

 

 

 

 

 

The drivetrain exceeds expectations--crisp shifts, firm brakes, and awesome looks.
Perhaps the best all round groupset for performance and price
Wow! This groupset is amazing! Shifting is smooth and precise. This is a great setup for the price! Highly recommend this and Merlin Cycles!
Excellent groupset. Feels solid, shifts cleanly and quickly. This particular groupset came with all the necessary parts to install.
It's been over 7 years since I got a new gruppo. These are great--very smooth shifting.
Excellent group set that comes with full set of cables at a price lower than others without cables, great value great service and delivery
Top value product. I am an amateur enthusiast and this groupset gives the best VFM. Merlin price is unbeatable.
Shipping to Virginia, United States was much faster than expected. I really like the pick-a-part option to customize the groupset and the price was much better than anywhere else I've looked! This 105 5800 groupset is a huge improvement over my old 5600 groupset. I will be recommending merlincycles to my fellow cyclists!
Robust groupset, if you don't mind the erxtra weight in comparison to Ultegra, it's the go-to groupset.
Love this groupset! Merlin had by far the best price on the full groupset and arrived quickly and intact. 105s in 2018 are phenomenal for entry level riders, and great for more experienced riders, especially on a budget.
Uograde from Sora 8 to 105 11 speed... a whole new bike.. crisp shifting, nice braking power and even felt a little bit lighter... should have done this upgrade a long time ago.. awesome price, nobody beats merlin cycles... 5 stars.
Great Price and speedy delivery from Merlin. Everything there you need, first time user of Shimano, always had Campagnolo, but seems good value for money , easy to set up, time will tell !
Installed everything without any issues, after a little playing around with indexing my gears shifting is flawless. This was a pretty drastic upgrade over the sora groupset that was originally on my bike. Love it!
I moved from a Campagnolo Chorus 11 Speed to this so called downgrade and I feel its a much better groupset...oh did I mention its cheaper to replace as well?
Good upgrade groupset for my Specialized Allez road bike. All components are suberb and weigh less than the Soria/FSA groupset it is replacing.
Have had Ultegra and Force Groupsets in the past. This is on par with either of those with just a bit more weight at half the cost. I nternational shipping from Merlin was quick and arrived before some items bought the same day in USA. Great All around experience.
I purchased this for a bike that I travel with and as usual with Shimano products they just work. The quality is there the 105 is better than the Ultegra that I was riding just a few years ago!
I bought the very first Shimano STI Ultegra group in 1992 and have been riding Shimano for 27 years and have been very satisfied. I bought the 105 5800 group for a new build and have put 300 miles on it in the first week. It has performed flawlessly. Shifts are quick and very precise. I really like the black Matt/gloss finish too. I would highly recommend this group and Merlin Cycles price cannot be beaten anywhere!!
Great value groupset! I can't believe how well it works and I was able to get a lower range of gears and not loose my top end gear ratios. I'll be recommending friends to get this group for many years.
Fantastic groupset! A few parts are heavier than Ultegra bc they are made from aluminum, and yet there is a $200 savings! That could buy a set of wheels for training ! Love it!
There are myriad positive reviews of this groupset out there by the cycling press and user forums. I agree with them all. Installed onto a 30 year old Cannondale frame, and now rides like a new bike.
Runs beautifully & amazing value for money. Have to say I'm pretty happy with this purchase, upgraded from my 3 year ol Claris/mix Sora to the 105 groupset. Didn't realize how much difference it could be. Fast and smooth! Superb shifting, amazing breaking performance, and it`s crazy silent. I was really looking forward for this upgrade and I'm really glad that I did.
Outstanding groupset. The 105 5800 groupset will function as well as the Ultegra groupset but at half the price, specially if you purchase it from Merlin Cycles.
A killer deal on a great group set. 105 is a great bargain as far as group sets are concerned, made even more so by this pricing. It works just as well as ultegra as long as you don't mind carrying along a few extra grams. Shifting is light and crisp.
Unbelievable value for money, really smooth shifting, and an epic upgrade from 10speed to 11speed. Great service by Merlin, product arrived swiftly!! Def recommend!!
A very good groupset, with almost the same characteristics as Ultegra 6800. Why spend an extra 200 quid for 170g less? Functionally, they'll feel quite similar.
I upgraded to a 105 set from an old Shimano RSX groupset, and the difference is astounding. In terms of weight and responsiveness, I feel like I have a whole new bike. I'm not doing any serious racing, so I couldn't justify putting an Ultegra or DuraAce set on my old steel frame, but for commutes and long weekend rides the 105 is perfect. The set was relatively easy to install by following instructions on Shimano's dealer manuals, which are all available on their website. The only drawback on the DIY approach (which was to be expected) was all the specialized tools I had to purchase. Word to the wise: pay careful attention to component compatibility when shopping for new tools, especially for bottom brackets.
Woke up my bike no end, smooth gear changes brakes work very well gear changing is effortless. Excellent upgrade. Its nice having the extra gears on climbs
Lightweight and precision in a cheap groupset. A great use for those who are starting and looking for good equipment. Thanks Merlin
Bought this after having a bike fit and he recommended I should use 165mm cranks. Decided to replace all my old 9 speed tiagra in one hit as I had been eyeing up 105 for a while. Stripped and cleaned the bike and installed over a couple of nights. All fairly straight forward fitting it except the front mech which I always seem to struggle with, but got it done anyway. First ride out was 47 miles of smooth running easy changes and much improved braking performance. Very happy with the extra gear range and smoothness. It was like riding a brand new bike. Fully recommend if your tempted by this groupset.
Superb groupset, great shifting, easy to fit and adjust. A quality product.
What a difference this makes as an upgrade to a 2016 Sora Groupset with FSA Vero Chainset that came as standard on my CAAD 8. The difference is staggering. Don't get me wrong, the Sora groupset is perfectly adequate, but downshifting is nowhere near as precise as 105, and the front Derailleur operation is like night and day. At this price, it's and excellent upgrade to bike that came with a decent frame but budget wheels and groupset. The 105 upgrade has really made it so much more enjoyable to ride. Will it make you quicker? No. Will it make your gear changes more precise, smoother, and the bike a whole lot more enjoyable to ride? Absolutely. I also have effectively given myself a couple of extra options at the top and bottom of the cassette as I've gone from 9 Speed 12-27 to 11 speed 11-28. The concealed cables look so much better too. Really pleased with this groupset. Top notch.
I bought this group set for a restomod on my old 85 Peugeot. It is fantastic! Super easy to install and setup. Gear shifts are quick and precise, the brakes are excellent as well. Love the 11spd drivetrain, so much better than the original 5spd it replaced. So many more gears to choose from. The sti shifters are so nice and smooth and easy to operate. I recommend this drivetrain for anyone wanting the 11spd upgrade, you will not be disappointed.
The groupset comes without installation instructions for beginners like me, but they are easily found on the Shimano site (http://si.shimano.com/). I followed the instructions to the letter and everything worked perfectly. My bike feels like a new bike. Smoother shifts than my Sora, looks cleaner, feels stiffer. The only very minor thing is rattle from the left shifter that I have not yet got to the bottom of. Very good kit at a keen price.
The 5800 group is awesome. I bought this for my commuter, after having a great experience with a 6800 group on my road bike. It's definitely not as full on as the ultegra, but an amazing group for stupid cheap.
I replaced an older ultegra 6600 group with this 105 5800 group, and I am very pleased with the performance and improved ergonomics. I did the switch myself and the components were easy to set up, but I've always worked on my own bikes. Shifting is improved over the older group, mostly in the front and the brakes are much more effective. This is a great price on a great group and shipping was really fast to the east coast of US. I would highly recommend it if you are thinking of 11 speed upgrade or build.
Brilliant group-set for the price! Smooth-shifting, nice-looking and easy to maintain. It replaces a Campagnolo Centaur 10spd from 2012 and on most aspects (of course) is a nice upgrade. Ergonomically, not as good, though, but all in all very nice. Used on my winter training road bike... Very speedy delivery from Merlin - amazing!
Bought this for a CX / Gravel / Adventure build, so reliability is my main concern, weight not so much. As always, Shimano is built to last and it just works, in all conditions. Very nice groupset, high quality and appears to be more expensive than it is!
That group is simply perfect. In my opinion it is the best choice for an amateur cyclist.
Great groupset, as has been said many times before. Upgrading from 9 speed Tiagra on Spesh Allez - no issues, easy setup, bike like new again! Excellent service from Merlin, fast delivery, will use again.
This groupset is a replacement for a frame that had really old 105. The groupset looks awesome and has very smooth shifting. I had a friend help me install it and everything was pretty straight forward. If you are considering this product I recommend you pull the trigger. The price in this item was too good to pass on in my opinion. No regrets here.
You can not go wrong with this groupset. This will be for my second 105 5800 road bike. I wanted to build a new bike for my commute without spending too much. I like that the feeling of ridding it is so similar to Ultrega. If weight is an issue for you, then go Ultrega or something lighter. For me the price was the main driver. I ordered Wednesday morning and I got it Friday evening, I live in Seattle WA. As always the service from Merlin was great.
I had a bike with the Shimano Tourney groupset and built a new bike with this groupset . It was the best upgrade possible. Smooth shifting, good braking and a nice range of gears. It was certainly the groupset with the best value for me.
I bought this groupset to replace Sora groupset that came with the bike and it is just sublime, the shifting is so much smoother. Came well packaged in no time thanks Merlin Cycles.
Absolutely fantastic - coming from 10spd Ultegra to this I thought it would be a step down but its crisp - perfect shifts and looks great too. Just the Front derailleur is a nightmare to setup - instructions not as clear but once setup rewarded with effortless front shifting regardless where you are on the cassette. The new dual pivot brakes are awesome
I pace line cycle 4 days per week at B-Pace at minimum of 30 miles each ride. I upgraded from a base SRAM groupset to this. The shifting is real smooth, and the components feel tight. Upgrading to this feels like a brand new bike! I would highly reccomend this upgrade, if you did not want to purchase a new bike, and just get another year out of the current bike.
Very easy to fit this kit on my 2009 Specialized Allez, and runs like a dream. Definitely a big improvement on the 2009 duracace kit that I had which had seen better days
There's very little to say about this groupset that hasn't been said before. The braking is brilliant, the shifting is light and accurate - the front shifting with multiple trim positions is a particular highlight. The hoods are comfortable and the internal cabling makes everything super tidy. It also looks awesome. At the price Merlin is charging you have no excuse not to get this groupset!
Top quality groupset, very smooth shifting, brakes are unreal.
After 8000 km still like new. I only changed the chain.
Excellent piece of kit. Smooth changes, even under full load. The brakes are excellent. I can't see how Ultegra would would be any better other than a slight saving in weight. Transformed my rides!
Absolutely beautiful groupset with super-smooth shifting and most definitely good-enough-for-me weight. Time will tell on durability, but I expect the small weight penalty over Ultegra will factor in even more for long-term use. The only gripe I can think of is the oddly shaped plastic cap for the non-drive side crank - why isn't a small plastic tool for this included if the bottom bracket adapter is?
Only been using it for a few rides but already feel the difference. I was using a 9 speed Sora prior and going to an 11 spd 105 was a big difference. The shifting is smooth. But because of this, it took some getting used to with how little I have to move the shifters to change gears. This is most true with the front derailleur - I found myself switching from big ring to small ring a few times during my first ride. Definitely some learning curve for people going from a lesser groupset. Overall, very happy with my upgrade and the price from Merlin made it even better.
This is simply a remarkable product and the pricing makes it an extraordinary value. I upgraded an older CF frame from Ultegra 6600 components/Gossamer crank/Tektro brakes to this and could not be more pleased. All the positive performance comments you've seen on the web are true. My only criticism is that the instructions are not very crisp. If you're experienced in cycle repair, you'll easily figure it out. Plus, there is ample support at any number of web sites, not the least of which is Shimano's own download page for dealer manuals. Merlin is exceptional: I ordered on a Saturday and received this on the following Wednesday in Los Angeles, an ocean and a continent away. What a great time to be a cyclist!
Quality Shimano parts that arrive before expected. Have only been on one ride due to illness, but beautiful and smooth opperation. Gained 2km/h with what seemed like no extra effort
Amazing update to the 105 group! Shifts so smoothly and precisely with light action from the levers. Runs silently as well. Love the adjustable lever reach and the look of the matte black with gloss black hits. Amazing price as well - thanks Merlin!
Awesome product and a great value. Easy to set up and adjust; operates so smoothly.
Really like this 105 groupset. The crankset is made out of aluminium and t's not heavy at all. It has a black matte finish that matches the brakes, levers and rear derailleur. The BB comes with a plastic tool that makes the installation of the cups easier. Overall it has really good performance and it's easy to adjust.
Sharp, responsive and smooth shifts everytime. Brakes seem a tad on the heavy side but not by much. No complaints, this group is an extreme value for the cost
Bought as to build up a bike from scratch on a carbon frame set. The groupset turned out to be the highlight of the bike as it is of such high quality and shifts so much lighter than the older 10 speed versions. Quick delivery from Merlin, and when I had a blip and sent a shifter back, they had it returned to me working within a couple of days! Awesome service guys, thanks! Great value and smashing bit of kit for the price of a few bits of ultegra, you can have the full gruppo with 105 which in my mind is almost identical bar slight weight difference which you can save by eating slightly smaller portions
As everyone says the set itself is amazing! I upgraded from the Shimano Sora set and I can definitely tell the difference. I also want to say that I had a great experience with Merlin Cycles. Being from the US and not very experienced with buying stuff out of the country, I was a bit wary to order. All items showed up quickly and without any customs issues at all. My order only took 4 days to ship to California. Will definitely buy from Merlin again!
Great groupset, it looks nice and shifts super smooth. I chose the 36/52 up front and 11-32 in the back, it lets me spin when needed up the hills, but still have plenty of power on the flats.
Excellent groupset. Quick accurate shifting!! Really smooth.
It's Shimano 105 in 11 speed, what else is there to say? It works and works well. At this price point there is nothing more consistent and reliable than Shimano 105.
It's Shimano 105 5800 - nobody ever got fired for buying that. And it's great - solid ergonomics, really smooth shifting, solid without being too heavy, and I personally recommend the 12-32 / 36-52 gear ratio, it has massive range for climbing and flat-out speed. Semi-compact with none of the knee-knack on hills. The only slight issue (as with all Shimano gear shifters) is they are a bit fiddly to operate from the drops when you have cold hands and are wearing winter gloves.
I upgraded the old 600 groupset on my 93 trek 2300 and couldn't be happier with it. It took 4 lbs. off my bike. I highly recommend the 52/36 and 11/32 combo. I was also very impressed with the shipping time, it came way before the advertised delivery date.
First impressions. Removed stock Shimano Claris components from my 2014 Jamis Ventura Sport. Everything installed smoothly. I mistakenly ordered braze on front derailleur, so I acquired a strap on adapter. The weight off my bicycle was apperant. Shifters click with less pressure. Brakes are stronger and responsive. Extremely happy with my upgrade.
Upgraded my 5700 105 to this 5800 105. The difference is outstanding! The shifting is so crisp and direct and changing from the small ring to the big ring has never been easier. Can't believe the difference from a product with the same name. A1 groupset. AWESOME!!!
This groupset is AWESOME. The guys at MerlinCycles are the best and I will never make large road bike purchases without looking to them first.
Upgraded my wife's 10 year old Lightspeed with this groupset -- what a difference. Smooth shifting and braking, and all 22 gear combinations are available, due to Shimano's additional trim positions for the front derailleur. Highly recommended.
The latest 11-speed Shimano 105 groupset is a quantum leap forwards. This is the third one I have bought. Having initially refitted my wife's 1994 Cannondale R400 then building my son's latest road bike with 105 5800, I decided to upgrade my 1989 Raleigh Road Ace to use as a winter bike. The groupset rivals the performance of the Dura Ace 9000 I have on my best bike. Every aspect of it is feather light and precise. The brakes are powerful, progressive and so light to operate that my 13 year old son can safely ride on the hoods as well as the drops. The 4 positions and the way the trimming works on the front mech means one never drops the chain once it is set up correctly... and by carefully following the dealer documentation from the Shimano website, it is easy to set up the groupset really well. I can't fault this fantastic groupset.
Not bought a new groupset for quite a few years but Merlin were offering a great deal and I've shopped before and had great service. The groupset arrived next day! The description said all items were boxed - this was not the case, only the chainset and front mech were boxed, everything else was bagged. Everything was there as described so this not an issue for me. I am happy setting the individual components up but the front mech needs the full instructions off the shimano website as they are not provided in the box. Follow these instructions and it is easy to do and works perfectly from the off - no fiddling required. Like the rest of the reviews say, the groupset works really well and is so light on the upshifts you are in danger of pushing the levers too hard to change gear - refreshing change! The new brakes look a bit industrial but are fine. The shifters are ok but still a bit long in the body compared to SRAM and the exposed mechanicals look a bit cheap but these are the only 'criticisms'. Overall very impressed but it is all new stuff with one 100 mile ride on it but if I am saying this in 3 years time then it really would be a proper bargain. Its not ultegra or sram but can't see how it falls that far short in performance except in price.
This group just works. I've previously had Shimano 105 5700 and can honestly say this is definitely an upgrade. Once set up correctly, its never missed a shift. So good in fact I find it hard to distinguish the difference between it and Ultra 6800
Fantastic groupset. I upgraded from a 2006 9 speed shimano 105 triple with FSA gossamer crank. This shed nearly a half a pound of weight and shifts like butter.
Absolutely perfect! Love the ability to customise the gruppo to my own preference, and the price is below what my LBS pays wholesale. The upgrade from Sora to 105 is like getting a brand new bike! Smoother shifting, more solid feel to the lever action, everything just feels "tighter."
This groupset is amazing! The ergonomics of the new shifters allow for a better and less tensioned hand placement. The new front derailleur design pops the chain up to the big chain ring very fast and it feels very light when shifting at the lever. Brakes are solid, and the rear derailleur shifts well too. I would highly recommend getting this groupset. If something breaks, the replacement parts would be cheap to acquire.
Absolutely fantastic group. Smooth shifting, quality built. Not much different from ultegra. Highly recommended group.
Should have called this group 105 6800. Its pretty much last years Ultegra. smooth shifting, hollowtech crank arms. 4 arm spider on the chainset, etc... bought this and a new 11 speed compatible wheelset and dropped close to 2.5 lbs off my bike. Great purchase! def not the old 105!
Excellent product, made my bike like a brand new bike. The shifting is now effortless, and everything is very quiet and smooth. Best price on this groupset as well.
It is just amazing, I've put cca 500 km on in just under 4 days and it impressed me. Smooth shifting, and amazing brake power. Feels like a pro set for half price. And it also looks cool :D
Converted from 9 to 11 speed. The 11-speed 105 is an amazing deal on a truly refined groupo. Everything was perfectly packaged and included all accessories. Advice - When going to 11-speed, make sure your derailleur hanger is PERFECTLY straight or you will have problems. You might want to pick up an alignment tool for your home shop.
Tight shifting, no need to shift twice to move from low to high on a double, unlike older versions, great range.
105 are a great group set. My previous experiences are that they perform well but are far more durable than the more expensive group sets. As I don't compete but do ride lots of semi fast group rides I wouldn't choose anything else.
Purchased this groupset (along with new wheels) to replace the Ultegra 6700 on my training bike. After putting in a thousand miles, I have to tip my hat to Shimano (for the groupset's quality) and Merlin (for their pricing). Dialled in correctly, shifting is light and accurate. Superb value for money.
This 5800 groupset replaces my four year old 105 5700 which has now allowed me to make a winter bike. It shifts much better and has adjustable reach levers rather than the fixed plastic shims. Brakes have a better feel. Did have a problem with the left-hand lever rattling but was quickly replaced under warranty. Did consider Ultegra but this is very cheap and just as good for the money and usual excellent service from Merlin.
This 11 speed groupset replaced my Shimano 105 10 speed groupset. It shifts better, has a nice trim feature, brakes are way superior to my original Shimano 105's and I love the adjustable hand levers. I give this a 10 in my book.
I used this groupset to build a summer bike, upgrading from Sora. Relatively straightforward to fit although a torque wrench and proper cable cutters are very useful. The hoods are certainly an improvement and feel very comfortable indeed, gear changing is a little slicker and with the 11 - 32 cassette I have greater range than the triple it replaced. Everything including cables etc you need is in the box.
Great price, works just like 6800/9000, but much cheaper and a little heavier. The only problem is the poor selection of cassettes Shimano has produced at the 105 level.
Looks and performs great. Fitted on my first ever road bike. I have ridden other bikes but nothing compared to this group set. I have been using my friends bike which has the next Shimano group set up pricewise. I`m sorry but the 105 Shimano Groupset is on par if not better than the Ultegra.
Bought this as an upgrade to Shimano 105, all arrived safely the next day, fully boxed, but with no instructions, these have to be downloaded from the Shimano website. Once set up the difference from was 105 was really noticeable, the shifting is smooth and precise, the brakes are a massive improvement, the overall feel is of quality throughout, it basically feels as though you have a new bike. Great price and service from Merlin.
Very nice group for the money. I bought it to update my son's race bike and he loves it. Very smooth shifting and spinning, and crank set/bottom bracket is rock solid; 11 speed cog is nice to have too.
Basically last year's ultegra. It shifts beautifully, brakes in a way that really inspires confidence on long descents and looks great too. I like the feel of the hoods, they feel solid and are confortable. As an entire package the 105 group works together flawlessly, and for a price that's unbeatable.
Excellent offer on a fantastic group set. Was looking to upgrade my 20 year old components, which worked fine until my rear wheel collapsed requiring a custom rebuild in order to still be compatible with my antiquated setup. I could not find anything which came close to this in terms of quality and price. Not only recommended, I would buy it again if I had a second bike to outfit.
In a word - excellent. I installed this new 105 groupset on my 2011 Trek 1.5 as an upgrade from a mismatched factory group. I could not be more pleased by Merlin's packing and shipping of the group. With the proper tools, removal of the old and installing the new 11 speed 105 group was easy. Please make sure you check with Merlin to be sure your freehub body can fit an 11 speed cassette. In terms of ride quality and improvement from my prior setup, it feels so incredibly efficient and makes riding much, much better. I would highly recommend this as an upgrade from a lesser factory groupset on any bike!
Great groupset, shifts really well, I have ultegra on another bike and really can't tell the difference, very smooth actions. Highly recommended if you want to slap a set of decent gears on a winter bike.
I am not given to hyperbole but this groupset has transformed my bike. The shifting is slick and the brakes will almost stop:-)you on a sixpence. I upgraded from 105 5600 and the hoods are slightly longer so I had to adjust the rotation of the handlebars to regain a comfortable position. I just want to go out and ride my bike all the time since fitting it. If you need a new groupset put this on your wish list.
Brilliant groupset. I have Dura Ace 9000 on another bike and this compares very well - levers are the same shape, gear changes almost exactly the same quality and brakes are very strong and with progressive lever feel. The chainset is ideal for a stealth build - looks great with a kind of matt finish as opposed to the cheap shiny black of 5700. I was very well looked after by Merlin for this purchase - win, win!
Required a new groupset for by winter bike frame, 105 is the perfect choice for a winter bike after using the 5700 groupset which is reliable and cheap. I opened the box but surprised to find no instructions for the fitting and tweaking of the individual parts, you have to download these from shimano`s dealers fitting instructions when printed of took half a ream of paper with lots of irrelevant stuff. But you DO require these instructions as there are aspects of fitting the front derailleur, sti's and cables that are different from the 5700 groupset. The 5800 groupset works well with very smooth shifting, although the brake calipers are a little disappointing, I expected a little more power after reading about the upgrades, nowhere near as powerful as my Sram force calipers, they will be the only upgrade I will make in the future. The only susceptible difference between the 5700 and 5800 is a slightly smoother gear change 11 speed is not noticeable, and so if the 5700 was significantly cheaper I would recommend to buy that, but in fact you can buy 5800 cheaper so buy it if you require a cheap reliable high performance groupset that is also better looking than the previous model. Just remember to order paper and a new ink cartridge with your order.
Upgrade from Sora 9 speed, triple crank. Fantastic. Shifting feels very precise and smooth, it seems to hold up and not need adjusting as often. Double compact with 11 (11-28) speed is giving me the range I need, flats, descents and hill climbs. Braking is amazing - doesn't require as much effort but still strong and responsive. Merlin delivery nice and fast. Will use again.