Is it just me or is 12just a bit crap.

I’ve done 2 wet-ish rides and it doesn’t shift properly. When it does shift it sits in gear nice but I have to overshift to shift back. It’s not cable stretch as it sits in gear nice. It just doesn’t like mud. Full length outer btw.

My 10sp I just fit and forget until I wear the cassette out or smash it to bits!

Brand new drivetrain, no crashes (on the mech side anyway! Haha

It’s SRAM so i fully expected it to be crap, but not *this* crap! I think the tolerances just don’t work off-road in the mud.

Can you get 10sp SRAM freehub compatible cassettes?

It’s you.

I’m happy with mine, don’t get any problems like that.

Years on 12 speed SRAM now. Absolutely faultless

It’s you.
Had no issues with XX1 Eagle shifter and mech with GX cassette and chain for 16 months now.

Shifter and mech bought second hand off here. No way I’d pay retail for them.

Also got an E13 kit to change 11 speed SRAM shifter to 12 speed. That worked, too.

Did you use the proper tool to set the derailleur?

I’ve found sram 12 speed better than shimano.

You do need to set it up correctly including with the b screw adjustemt tool. The new tool included with the 520% range is better than previous.

My 12 speed SLX sounds a bit gritty in mud, but Sram and Shimano have all been great with shifting.

Just sounds like it’s not set up/installed properly.

If its lower than Gx level then yeah the mechs are probably not fit for purpose.
Gx and above are fine if a little fragile and vulnerable.

I’m finding this with 1x 11spd on an 11-40 cassette.

I thought it was set up correctly because until now I’ve always found drivetrains really simple to set up and keep set up, but 11spd (and I assume 12spd) with big cassettes especially just seem to need a bit more finesse.

I eventually got mine working by just tweaking things in increments when out riding, needed more B-Tension that I thought it would.

Is it just me or is 12 9 just a bit crap.

8 speed was the pinnacle. All downhill since then.

Yup, 12 speed SRAM and Shimano are a PITA in muddy conditions and require too much fettling. The tolerances are tight and the slightest tap on the mech hanger will screw up shifting. They are also useless on ebikes due to the 10t cog. 11 speed and 10 speed were a lot less hassle.

Yes can agree to a degree. Generally happy but having a slight issue on two bikes with 12spd:

Shimano SLX/XT derailleur
Sunrace cassette
New cables and outers
checked cassette lockring
hangers look straight

Shifting all adjusted and works well in the stand but out on rides in the middle of the cassette I sometimes get no shift down or up 1 click and have to click a second time then go back. Just happens in those middle couple of gears.

My 10sp I just fit and forget until I wear the cassette out or smash it to bits!

10 speed absolutely is easier to set up, is more tolerant of poor set up, and also more tolerant of abuse. 12 speed on OEM builds tends to work as well, if not better, than anything… 12 speed home mechanic builds are more hit and miss.

[ personal opinion not fact ]

8 speed was the pinnacle. All downhill since then

Nah, DH is 7 speed.

If its sram, you need a XO1 rear mech to get something that lasts.

I’ve never been a mech breaker but I went through two GX mechs in 6 months when I went 12 speed in 2018. XO1 has bee fine since.

At least 2 others who I ride with have had the same issue.

12 speed needs more careful setup than 10. The plastic tool is great for SRAM but I think Shimano have some markings on the mech itself to help get B tension right.

How do you set them up?

Like I said it sits on the gear right (no clicking/skipping) when it gets in the gear so I guess the mech/cog lines up correctly.

That’s all the setup I’d normally do with a 10sp setup?

It’s a brand new bike setup by a shop. 2 rides old.

It is muddy. But then it will be for the next 6months!

I wouldn’t normally clean my bike after 2 rides. It’s a waste of time and they’ve never needed that kind of maintenance. I’ve even dug out my chain cleaning device (used twice in 10yrs! Lol) to see if that may help.

It is muddy. But then it will be for the next 6months!

Singlespeed for the muddy months!

DrP

“Is it just me or is 12just a bit crap.

I’ve done 2 wet-ish rides and it doesn’t shift properly. When it does shift it sits in gear nice but I have to overshift to shift back. It’s not cable stretch as it sits in gear nice. It just doesn’t like mud. Full length outer btw.

My 10sp I just fit and forget until I wear the cassette out or smash it to bits!”

I concur. I hardly did any cleaning or maintenance with my Shimano 10 speed stuff, it just worked. GX Eagle is far less tolerant of use in nasty conditions.

-11 speed Sram was good, shimano was a bit meh to be honest.

-12 speed sram is garbage, the mechs lose their clutchyness inside of 6 months, less if you are
really unlucky.

-12 speed shimano is a big step on from their 11 speed and blows sram out of the water. Crisp shifting, proper adjustable clutch, bombpoof. Microspline is slightly annoying if you have lots of xd drivers.

I ‘ve run 12 speed Sram for 18 months now (shimano 11 speed before), and thankfully it has been flawless. Not sure if the fact its not mechanical plays any part (AXS X01 setup)

Pretty much 11 months of constant mud up here in Scotland and the SRAM eagle 12 speed is faultless. Never fails to shift smoothly and cleanly and needs zero adjustment ever

Two years on Sram Eagle GX all I’ve had to do in that time is adjust the b gap screw once. I’ve still got the same chain and cassette after 2000 miles and it’s all still good.

Agree so far – my XT 12 speed is perfect until it gets a bit wet and gritty / muddy then it’s either noisy or trying to skip (maybe a bit of both). Chain length done using the Shimano manual method and the same with the b screw adjustment using the mark on the jockey wheel cage. Apart from the chainring it’s all Shimano 12 speed stuff (chainring has hg12 compatible tooth profile).

Bent mech hanger (usually the culprit)
Poorly routed cables
Cable tension needs adjusting
In highest gear (smallest rear sprocket), mech rests on the cable tension instead of the limit screw. [the Park Tool web page on adjusting rear mechs has a great description of why this can cause a lot of issues]
B screw not adjusted properly
Cable inner / outer / both need replacing.
Clutch friction needs adjusting
Mech needs cleaning / lubing
Frame out of manufacturing tolerance (very rare)

Could be any one or a combination of the above.

Chain length done using the Shimano manual method and the same with the b screw adjustment using the mark on the jockey wheel cage.

What mark on jockey wheel cage? Wonder if there’s a GRX equivalent, manual doesn’t mention anything though.

I might go and check chain length, my suspicion was that it was too long by a link…

7 months and 1600 miles on Deore 12 speed.

The mud killed the chain pretty quickly as soon as the weather got bad. Shifting was noisy, but still functional.

Before that, it was solid.

New XT chain gone on this week and I’ll see how it goes this weekend.

It’s odd people are suggesting maintenance/replacing when I’ve said its brand new, 2 rides old, shop setup😂

Still I’ll give it a Zzap with a hose, clean it all, and see if its just crap in the mech or just crap in general.

Might be b screw I suppose. I’ll see if I can get the mech closer to the cassette.

shop setup😂

Having seen forks on backwards on display stands and things over the years I’d like that to mean more than I know it does.

It’s odd people are suggesting maintenance/replacing when I’ve said its brand new, 2 rides old, shop setup😂

As above. This means nothing.

Two new bike I bought from reputable shops came with bent mech hangers which the said reputable shops didn’t pick up on during assembly.

Once I set up my new bike’s mech properly at home with the Shimano instructions (unlike the bloody useless shop it came from) and perfected the hanger alignment my 12 speed xtr has been great.
As it came from the shop it was woeful.

On XT and SLX 12 speed and the new style Deore 11 speed mech there’s a mark on the back side of the mech above the top jockey wheel. On the XT / SLX it says ‘51T’ next to it. You’re supposed to adjust the b screw until the tip of the big tooth cog line up with it.

With chain sizing it’s not plus 2 links or anything quite like that – there are different sizing based on ht or fs and how the chain sits when you route round big cog / chainring but not through the mech. Done 3 now. Cant say I love these new style Shimano mechs – 11 speed Sram was far less sensitive to the b screw setup.

I’ve got 12sp SLX on my new 29er fs. Anybody had it not shifting down from the biggest sprocket when the clutch is engaged? Thought it was the cable but took the cable off and it does it without.

Place where I had the bike said it needs a new clutch mechanism but the bike was new in July. They’ve sent me a new clutch innards which I’ll try fitting tomorrow and see how that goes.

Still on old 9 speed XT, however its just aboot fecked. I’m looking at 9 speed Box Components as a replacement, anyone used their drivetrain yet for comparison?

No problems with my GX or X01 setups, my previous X01 cassette was still going at 2000+ miles and accepted a new-ish chain too! The X01 shifter is was better than GX, but found GX mechs more than enough and no dodgy clutches for me.

Both Sram and Shimano dropped the ball with 11-speed. Sram felt cheap, plasticky and nasty no matter if you had NX or XX1 and Shimano lost that light, smooth feeling so it just felt like the worst of both worlds. I did love my 10-speed Saint shifter teamed with an XT clutch mech and XT cassette with Hope T-Rex though, that was great setup but a bit short of range these days!

It’s odd people are suggesting maintenance/replacing when I’ve said its brand new, 2 rides old, shop setup😂

Its odd that you think this means it cant be anything else other than 12 speed simply being shit.
Its more likely that the shop didn’t do a great job setting it up. From your posts it sounds like you dont know how to look after you own bikes or just choose not to care for them properly and rely on shops to do it.

Maybe you should try look at some very simply and easy to follow tutorials on youtube instead of making a pointless thread with a ridiculous title.

Best of luck.

No issues here in the last few years, with a full GX setup, XTR and hybrid AXS/XTR cassette/Praxis chainring/KMC setup.
The GX feels a bit clunky but shifts fine, the full XTR was an absolute dream and the only weak point on the mish mash setup i now run is the worn Praxis ring picking up the chain on the bottom when it’s really mucky. It is 2 years old and not technically a 12 speed ring though. Have an Eagle ring on the way tnsort that out.

Agree so far – my XT 12 speed is perfect until it gets a bit wet and gritty / muddy then it’s either noisy or trying to skip (maybe a bit of both)

Top tip: Fit a SRAM chain in the winter. You’re welcome 🙂

@benpinnick

Top tip: Fit a SRAM chain in the winter. You’re welcome

That’s interesting – I’ve always run Sram chains / drivetrains on modern mtb’s – this is the first Shimano one in ages. I believed a lot of stuff online that suggested for the best shifting on new 12 speed you needed a Shimano chain. Hence having one on my setup.

Tempted to pick up an oil slick Sram chain in that case as they look nice and bling!

Just because a shop set it up doesn’t mean it correctly done but my factory built bikes needed a bit of a tweak.
I’ve been running full 12pd X01 for over 2 years now and it all runs smooth,only difference I have found is the adjustments are very fine compared to 10/11 spd Shimano/Sram which you could be less spot on with.