Shimano release GRX 820 and Mech. 105 R7100; both 12sp, disc only

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wafter

I like steel bikes and I cannot lie..
Location
Oxford
For those who don't know, since it doesn't seem to have been mentioned on here yet.

Bikeradar has a decent summary for GRX here and 105 here.

Not of huge interest personally as I'm not in the market for a complete new groupset and being 12sp most of the new bits are unlikely to be compatable with what I already have.

I'm very happy to see that Shimano have seen sense and retained a mechanical version of 105, although slightly sad to see rim brakes disappear from this groupset as it means it'll be no use for the future retro-modern build I'll probably never do anyway. Also a bit sorry to see the back of 11sp since it leaves a bit of a no-mans-land for spares for my existing gear.

Shimano seem to have got more bold with the gearing options on GRX (although the new names are silly and so open to confusion IMO). Nice to see GRX has remained mechanical too..

I guess now's the time to get off the fence and swap to a GRX crankset and FD while they're still available if I'm ever going to; some end-of-line discounts would help in this regard although I've seen nowt so far.
 

fossyant

Ride It Like You Stole It!
Location
South Manchester
Spares for any speed aren't an issue. So don't worry.
 

chriswoody

Legendary Member
Location
Northern Germany
I've been reading about this new GRX groupset elsewhere and whilst I don't personally use Shimano stuff, I was initially quite excited to see a manufacturer come up with a groupset that uses a 10 - 51 tooth, twelve speed cassette with drop bar levers.

One of the big unspoken problems with modern gravel bikes is the gearing if you opt for 1x systems. 1x is my prefered drivetrain for a number of reasons, but sadly cassettes are limited to a 42 tooth top gear with drop bar bikes, because of the derailleur capacity. With 11 and 12 speed drivetrains, MTB derailleurs are not compatible with drop bar shifter, unless you are willing to hack things about and go for a mullet drivetrain. So to see a manufacturer finally realise this and provide a drop bar shifter compatible derailleur that has the capacity to go to 51 teeth, is quite exciting.

However, delving into the details and Shimano have really missed a trick with this. Firstly the crankset available are only compatible with 68mm bottom bracket widths which rules out using it on bikes like my Kona Sutra, which has a 73mm MTB width shell in order to allow greater tire clearance. Also the chainset only comes with either a 42t or 40t option, I mean really? do they think all gravel cyclists have legs like Chris hoy? I ride a lot of varying gravel trails on my bike and some of it is very soft and sandy, along with that I also do multi day off-road tours on my bike. The bottom gear on this setup is just not low enough, you need at least a 36t option or 34t ideally to make it truly versatile. The 2x option isn't much better, with a 31/48 crankset, mated to a 11-36 cassette.

Also they have used Micro Spline, a mountain bike standard, most 142mm standard gravel hubs, don't come in Micro spline options. As mentioned above, it also only comes in a disc brake compatible options and the brakes that come with this groupset are flat mount only. Again for serious gravel bikes, flat mount are dire, they will allow only a maximum rotor size of 160mm. For a lot of folk that may be fine, but I've upgraded my post mount brakes on the Sutra to run a 180mm front rotor, in line with my Mountain bike. This gives me a lot better braking when I'm bikepacking on loose terrain.

All in all it's good to see Shimano attempt this, but I would have liked a bit more thought to have gone into it. That said, If I were to use this groupset, I would probably only use the Derailleur and levers, the rest I would source from other manufacturers and create a franken group that would be far more suitable for a proper mixed terrain/bikepacking gravel bike. It may not shift quite as crisply, but it would work.
 
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fossyant

Ride It Like You Stole It!
Location
South Manchester
GRX comes in 2 for 10/11 ? 1x is a big compromise in places, works best on MTB if the bike doen't do much cross country, which is where you'd use a CX/gravel. Whoops. Much prefer 2x for my CX and FS MTB.
 
Good morning,

I am not sure if I should post this here or on the Grumpy old git thread but most new announcements from Shimano makes me think that they are drifting away from what the mass market actually wants.

Ultegra and DuraAce cover the serious competitor or the money doesn't matter customer and there are four other groupsets where most of the sales are.

I have recently changed from 2x10 to 2x8 and am not missing two extra sprockets at all, both are 11-28 losing the 12t and 14t in 8 speed.

I suspect experience of newer ideas like 10speed plus, CF frames and STI has become well established cycling folk-lore and there is a limited market of let's try it simply because it is new.

For many people buying a bike £500 is a lot of money and £1,000 a ludcrious amount, let alone £1,000 for a new 105 groupset. Okay on a complete new bike it would be a lot less but 105 used to be on bikes like the Raleigh Triathlon, a decent step up from carbon steel but nothing special.

I posted elsewhere about how high 10 speed running costs were, so 12 speed fills me with dread but I am likely to go back to 10 speed as I am really starting to miss Di2 (Sorry Cycleops

^_^
) and am really unhappy about being forced into 12 speed if I want new Di2.

Do I want hydraulic disks, especially when there is no-one local selling spares, of course not. If I get up one morning and need to I can replace the lever, rim brake and inner and outer cables from my junk bin in a few minutes. You may say that is not relevent as I have never had to, but that is my point just left alone rim brakes work for years.

So;

Dear Shimano,

Please make Claris, Sora and Tiagra 8 speed, with big jumps in quality so Claris stays as entry level and Tiagra is pretty much 105 in 8 speed form. Rim brake only for Claris, Sora and Tiagra in rim and hydraulic disc. 8 Speed Di2 would be nice but I can understand if the costs just don't work out.

105 as 10 speed with both rim and hydraulic disc in both mechanical and electronic shifting.

Ultegra and DuraAce as leading edge as you want.

Yours .....

Bye

Ian
 
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Kajjal

Guru
Location
Wheely World
GRX comes in 2 for 10/11 ? 1x is a big compromise in places, works best on MTB if the bike doen't do much cross country, which is where you'd use a CX/gravel. Whoops. Much prefer 2x for my CX and FS MTB.

When going off on natural trails in the middle of nowhere I use my 2x MTB’s as the granny ring makes steep climbs much easier work. 1x is fine for less varied and flatter trails.
 
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