Hi all.

I am looking for some single ring 170mm cranks. For fitting to an older non-boost Transition Scout with threaded BB with a 1×11 Shimano XT drivetrain. What would people recommend for up to £150 (but ideally less than £100)?

I have looked at Race Face Aeffect but what puts me off is that the 170mm version looks to be the same as the 175mm but with the pedal drilling further up (the fact that they make crank boots for the 175mm but not 170mm version suggests that is the case). Given that the reason I switched to 170mm was to avoid crank strikes I am not too keen on that as an option so would prefer a ‘genuine’ 170mm.

Any suggestions welcome.

M7000 SLX. I got mine for £95 with a chainring. Looks good, the writing wears off quickly but the finish underneath has stuck so far (3 months). I think they are within a couple of gm’s of XT weight wise. BB not included.

I guess I was a bit hesitant on Shimano as they are not narrow wide rings. What is your experience of chain retention using that crankset?

Even if they don’t come with a NW ring couldn’t you buy an aftermarket one (I’d be surprised if it was a ring without some features to retain the chain for 1x) and still be in budget?

They aren’t narrow/wide but they have shaped teeth to grip the chain for retention. I’m not running a chain device. I lost the chain twice in the first few rides, 1st time out I hadn’t engaged the clutch after refitting! Not dropped it since though – I clattered down campsite descent last night being deliberately aggro to test forks and it was fine. Only 3 months old so will be interesting to see how it is after more wear on it.

Another vote for slxm7000! No issues with chain dropping here.

Another vote for slx. Been running them for 20 months no issues with chain retention.

What about chainline dimension, is this a boost thing? The Shimano ones say 50mm would this suit my setup which is 142×12 at the back and threaded BB at the front?

Not sure. If you look at sram cranks they’re mostly the same and it’s the direct mount chainrings that have the difference in them – 6mm offset being non-boost and 3mm offset being boost.

I have a longstanding disdain for anything RaceFace that requires bearings or has any moving parts, mainly because I owned a very pretty set of Evolve XC cranks that lunched themselves at the spline interface. I’m not discounting a user error in torque settings, but I can get the same performance for less hassle with Shimano. Likewise, I am probably prejudiced against SRAM on the grounds of my history with their fragile BB bearings (I’ve used both the GXP and the 30mm axle variants, neither lasted much more than six months before sounding like a bag of gravel). Please take my comments with a pinch of salt if you’ve had better RaceFace/SRAM experiences than I have.

I’m a longstanding Shimano fan, both of my bikes are fitted with XT M8000. One bike has a 30T Hope narrow/wide ring and an aftermarket PF-46 BB, the other has the stock 32T chainring and an XTR press fit BB92. The latter bike is approaching it’s fifth year on the same BB, truly astounding longevity IMHO.

Interestingly, the chainring in my first M8000 is a non-narrow/wide but the chainring in the newer set is most definitely a narrow-wide type ring. Because chainring no 1 is still going strong with little or no discernible wear, I cannot comment on how the newer ring performs as it’s still unused!

Nearly new/new XTR cranks pop up on eBay for around £100 every so often. I was watching a few the other month and ended up getting some for £115, still in the box and never used.

Mine were marked as “boost” spacing which is a 53.4 chainline, I am running 148×12.
50mm chainline is the correct one for 142×12.

M9000, M9020 and M8000 all initially ran the tall non thick/thin rings, but latterly ran the newer thick/thin rings. M7000 only ever had a thick/thin ring option as far as I remember.

Don’t forget XTR 9000 series has that slightly smaller chain ring bolt even if the bcd and shape are the same…

Ive just had a chainset disaster in Les Gets….so what chainset has a steel insert for the pedal? Does SLX? Or will it have to be Zee or Saint?

Thanks

Ian

Zee, I kill cranks (big-ish bloke on hardtail, riding fash-ish quite clumsily?) and Zee are lasting well for me.

Ace, thank you