Groupsets

[Daveysnaps]

Hi All.

I’m after more help and advice... I’ve ordered a Cotic escapade but as a rolling chassis.
I need to decide on a groupset now and gearing. First question is 1x or 2x???
I’m pretty certain I’m going for GRX as have tried them and was hugely impressed with the shifters and hoods.
I’m keeping the Fargo for out and out bike packing so the escapade is really the weekend bike. Or road bike that will do some off roading.
Possibly thinking about Tiagra or 105 as a cheaper option.

What do you folks think?

[Lazarus]

1x v 2 x depends entirely in where you intend to cycle it

I use my CX bike as my commuter and its pancake flat for 20 miles a 1 x option [ given i ride everything on the big ring of a double with a 32 rear cassette] is less than ideal for my needs.


I dont share the obsession that 1 x must be better and always chosen but it really is personal choice
i also have SRAM and Shimano on both MTB and drop bar and dont prefer either , both just work IME.
SRAM is either a Bit clunkier or more positive if you like it
I would probably base my decision on price tbh rather than preference

[Gasman]

I have a GRX 1x on my Salsa Vaya. Basically the 600 setup with 40 tooth chain ring and 11-42 on the back. Love it. Plenty enough for the hills in the peaks, both on and off road.

[jameso]

I'm not a fan of 1x for general road riding, it works OK but I prefer the closer ratios of 2x. I have 1x on an Arkose X, a fairly light and quick bike, and the 1x isn't good for faster riding among a group. I don't mean roadie chain-gang pace, just anything 15-18mph or so where other riders influence your pace. I'm not fussy about cadence etc I just find the wider gaps of 1x disruptive or less smooth in that situation. But it's not a big deal really.
I also don't see the need for that level of chain retention on a road/gravel bike and the associated tech+cost in mechs, cassettes etc on a bike that does high mileage is a negative. But again, £50 a year or £200 a year, no biggie. Buy the one you like using or that makes the bike more enjoyable to ride - not much more to it than that.

[ScotRoutes]

I'm just rebuilding my VN Amazon and looked at GRX but decided on a 105 compact (50/34) and a 11-40T cassette. I've been assured that this will all work fine. Gives me a good range and a much better/cheaper choice of cranks.

[Asposium]

Never tried 1x
However
On my sequoia I wanted a low gear for easy climbing, and a fairly high gear for the road
With no massive cadence jumps
So, if building an all rounder then maybe 2x

If you want to be on trend then 1x

Keep in mind that you’ll already have the shifter for 2x

[stevenshand]

I'm just rebuilding my VN Amazon and looked at GRX but decided on a 105 compact (50/34) and a 11-40T cassette. I've been assured that this will all work fine. Gives me a good range and a much better/cheaper choice of cranks.

What rear mech are you using to get that to work?

[pistonbroke]

I built a very low gear gravel bike setup for Turin-Nice last year using Absolute Black 30-46 tooth oval chainrings on a 105 crank with 11-40 cassette. The rear mech is the standard cage 105 R5800 but with a Wolftooth roadlink to give enough clearance for the top jockey wheel, it wouldn't shift under load without it. It worked well and avoided the dreaded death march on the climb to Little Peru.

[jameso]

I built a very low gear gravel bike setup for Turin-Nice last year using Absolute Black 30-46 tooth oval chainrings on a 105 crank with 11-40 cassette.

I find it hugely frustrating that Shimano don't make this possible with std kit or for OE on bikes but it looks like some of the Microshift RDs can cover 11-42 as well as a 30-44 up front if you're careful with chain length. Then you have a mostly-1X type of set up, with a bail-out or loaded climbing ring up front.

[wriggles]

New R7000 & 8000 mechs work with a 40t rear cassette I believe - but not officially, which guess doesn't help someone thinking of speccing on a new bike.

Just gone GRX 30/46 Chainset on Camino. £78 from zee Germans. Very impressed so far, much smoother shifting (R8000 front mech) than the Ultegra triple with 30/46 rings hack I was using before. Also seems to have a decent finish that wont scuff as easily as recent Shimano chainsets. 36t biggest at the back covers my weedy legs around here. New 6800 rear mech covers that fine - only using that as it came with the Ultegra hydraulic shifters I bought.

If do TNR next year will put the M785 24/38 chainset back on as 24 front - 36 rear gives me a lower climbing gear than putting a 40t on the rear.

[ScotRoutes]

As of 15 minutes ago, I can confirm that 50/34 and 11-40T works with a Shimano R8000 rear mech. I needed to fit a longer chain - 118 links. That's on a chainstay length of 445mm. Cross-chaining to the max works with no rubbing. The rear mech isn't too stretched at 50:40 and still has some tension left at 34:11. No funny Roadlink required, nor longer B screw.

I considered GRX but it's only available in black , plus 105 cranks are more easily obtainable.

[wriggles]

Annoying thing I found with the new R7000 105 cranks on another bike is the crank arms started to scuff straight away. I dont mind scuffs, dings and scratches as they are part of use, but these cranks started to scuff on the first ride. Have put some helitape on there now.

[faustus]

Interesting to know scotroutes! Might be looking at an upgrade for my 5800 rear mech. I really don't need the higher end on the 50/34 105 compact i have, but it also seems a bit of a waste to get a new chainset. Out of interest what 11-40 cassette did you use? i've heard the chain retention is better on newer shadow r7000/8000 rear mechs, does it feel any better (guess it's a bit early to know)? I was keen on getting a clutch rear mech as when i'm off road on it more in the summer it clatters a fair bit in the small ring.

[ScotRoutes]

My cranks always scuff quickly because I pedal like a duck (heels inwards). It's less obvious with silver cranks too.



I'm using a XT cassette.

No idea on chain retention yet. This is a pre-clutch mech but it's not something I have much of an issue with anyway.

[Daveysnaps]

So given cost of GRX groupset is it possible to mix GRX shifters with 105 chainring and cassettes?

[Alh14]

Long time lurker, ‘ere.

I built up a GRX 1x with a SRAM 11-42 cassette and absolute black chainring this summer, works perfectly.

[Asposium]

So given cost of GRX groupset is it possible to mix GRX shifters with 105 chainring and cassettes?

Shifters are “road pull” so should work fine with a 105 front mech; a GRX front mech has a chain line shifted outboard slightly

Similar for the rear mech.

Essentially, don’t use MTB mechs and should be fine

A GRX double chainset requires a GRX front mech

My plan is to use a GRX double chainset and front mech with Ultegra shifters

[jameso]

As of 15 minutes ago, I can confirm that 50/34 and 11-40T works with a Shimano R8000 rear mech. I needed to fit a longer chain - 118 links. That's on a chainstay length of 445mm. Cross-chaining to the max works with no rubbing. The rear mech isn't too stretched at 50:40 and still has some tension left at 34:11. No funny Roadlink required, nor longer B screw.

Good result. Worth knowing the R8000 can cover it, thinking of something similar with a road chainset since it's easier than getting smaller rings and front mechs that work with road STIs. Plus I like the idea of spreading load over more teeth. 34-44 or 34-46 front rings would do well. In the end I'll prob just go with bar-enders but this is a useful option.

[ScotRoutes]

As of 15 minutes ago, I can confirm that 50/34 and 11-40T works with a Shimano R8000 rear mech. I needed to fit a longer chain - 118 links. That's on a chainstay length of 445mm. Cross-chaining to the max works with no rubbing. The rear mech isn't too stretched at 50:40 and still has some tension left at 34:11. No funny Roadlink required, nor longer B screw.

Good result. Worth knowing the R8000 can cover it, thinking of something similar with a road chainset since it's easier than getting smaller rings and front mechs that work with road STIs. Plus I like the idea of spreading load over more teeth. 34-44 or 34-46 front rings would do well. In the end I'll prob just go with bar-enders but this is a useful option.

I'd seen a video on youtube of this working but, you know, if you haven't tried it yourself, there's always a bit of doubt.

[Daveysnaps]

Thanks for all the comments folks.
Spent a lot of time thinking about this and speaking to friends also.
Most advice is going the 1x route for ease of running, setup and maintenance.
Speaking to guys at Cotic who tell me they spec GRX with 11-46 on the rear I was thinking that this with a 42 on the front would give me what I need.....
Now looking at ordering but note the GRX mech only supports a max 42 ?

[Boab]

I've gone GRX 1x with the 42T rear cassette, on the basis that that's what the Shimano website said would work. There is some chat about this on a STW thread. Scotroutes thinks you might need a MTB SGS rear mech and some sort of ratio converter.

[ScotRoutes]

If you are only going 1x then a standard GRX or Ultegra SGS mech will likely work.

[jameso]

Most advice is going the 1x route for ease of running, setup and maintenance

I'm not anti-1x or trying to be difficult here, but imo none of those reasons are really valid for 1x over 2x. Or, they aren't pros that would sway me either way. The first 2 are discounted if you can set up a front mech (it really isn't hard, once done it's done) and the maintenance aspect is the same, it's the chain that needs cleaning and looking after - get that wrong and it can be more expensive with 1x rings and cassettes. Not necessarily though.

[belugabob]

As of 15 minutes ago, I can confirm that 50/34 and 11-40T works with a Shimano R8000 rear mech. I needed to fit a longer chain - 118 links. That's on a chainstay length of 445mm. Cross-chaining to the max works with no rubbing. The rear mech isn't too stretched at 50:40 and still has some tension left at 34:11. No funny Roadlink required, nor longer B screw.

I considered GRX but it's only available in black , plus 105 cranks are more easily obtainable.

I concur - used this exact setup on my Kinesis 4S Disc, on a multi-day trip from Plymouth to Crawley (via the Isle of Wight)
Could have done with even lower gears than that, on a few of the Devon hills, but I am a bit of a biffer.

[wriggles]

Essentially, don’t use MTB mechs and should be fine

A GRX double chainset requires a GRX front mech

Currently running an R8000 Ultegra mech with a GRX 600 11 speed chainset. Works fine.
Also last summer set up an M785 HDM 10 speed mech with an M780 XT chainset on 11 speed with R8000 Ultegra shifters.
Front mechs are very forgiving - best to try things out.