Obligatory mud shot, to prove I got gnarly and ‘put the gear through its paces.’

SLX, the working man’s XT. The blue collar hero of groupsets.

This groupset is a ridiculously well priced contender in the increasingly competitive world of mid ranged, level headed mountain bike gear. Long gone are the days of jazzy anodizing and elastometers. We’re grown ups now who care about things like suspension curves and BB stiffness.

Installing the M670 groupset presented a great deal of firsts for me. The most exciting of which was undoubtedly un-packaging all of those little blue boxes and obsessively fettling with all of the goodies within. I’ve never owned a bike from new, so having the better part of a whole new one arrive within a 70cm cubed box was, to say the least, pretty exciting.

In regards to innovations from my previous two affairs with mountain bike groupsets, there were many. My last bike, a 2004 Marin Attack Trail was adorned with a 3x9 M760 groupset with admittedly excellent, Hope Mono M4s. And the groupset previously on the Blur was a mix and match of 3x9 M960/70 era XTR kit with absolutely atrocious Juicy 3s.

Both set-ups were perfectly fine barring the Blur’s Juicy’s. I still find it hard to believe that I put up with these unbelievably poor brakes for as long as I did. Even after a fresh bleeding, the performance was pretty dire.

The experience of having to use these brakes can only be compared to the sensation of farting publicly and minimizing the damage; The dread of the fast approaching drop, unwilling committal as you squeeze and try to close the pistons before the inevitable and unapologetic collision with public senses/trail-side foliage.

Dem brakes, dem shifters, dat bike.

So moving to the very well modulated and relatively powerful M670 brakes was an absolute joy. Chief amongst the improvements for me personally has got to be Shimano’s excellent ceramic pistons. Brake fade is minimal and could be further improved by an upgrade to ice-tech rotors and pads, but I’ve not felt this is necessary as of yet.

The move up to the crisp, precise and quiet shifting of the 2x10 setup is a joy. Particularly impressive is the performance of rear shifting under power. The groupset comes with an excellent package of cables which includes a very generous quantity of ferrules and seals. This is very useful for a bike like the blur which doesn’t have full length housing or internal cable routing.

The universally loved clutch mech is also universally loved by me. It’s unnecessary to dwell on this particularly as it’s just universally awesome

The most popular girl at the prom.

One thing that is moderately disappointing are the el-cheapo feeling shifters. I understand that costs need to be cut somewhere on a mid range groupset, but the flimsy feeling plastic shift levers are just a bit meh in comparison to my trusty old M960’s. This is especially pronounced on the front shifter when things get a bit sloppy; the feel at the lever becoming a bit vague as the front mech clogs up.

Also slightly disappointing is that the shifters were not i-spec compatible. Which would have made for nice clean bars. If I was overly fussed, I could swap these out with the XT equivalent for between £50>62 from a popular online bicycle retailer.

In the shifters defence, I do rather like the two-way release; it brings the down shift that little bit closer when seated which is rather nice.

Gregnar, my SRAM lovin’ pal also commented that the two way shift would make the emotional transition to Shimano far more pleasant.

Undoubtedly the crowning jewel of the of the groupset has to be the crankset. They are the perfect balance between masculine hard edges that highlight your passion for poetic-suffering on super duper steep fire roads and soft, fade to black graphics which prove you’ve like, got a soft side too.

As usual with Shimano, the cranks are more than stiff enough for your average rider. The admittedly cheapo looking chainrings perform very well with nary a missed shift. The black finish keeps them looking cleaner for longer too! Nothing one can fault here.

Oh and did I mention they’re 4 GRAMS LIGHTER THAN M780 XT?!

4g difference offset by ubiquitous Pentlands slop.

So suck it XT.

I can assure you that with these cranks, you’ll totally be wading through stoked mountain bike chicks, all eager to 'totally nail that’* and 'shred the gnar’ with you.

Overall, after my ~400km on the M670 groupset, it’s presented itself as a really well rounded and very functional groupset at an incredibly competitive price point.

The only things of note you miss out on compared to the M780 groupset are slightly posher jockey wheels and more cogs of the cassette being mounted to the alloy spider. To be frank, I even prefer the finish of M670 over M780.

I’d be hard pushed to recommend anything bar this to your average gnarly bro.

**Totally nail that berm, sicko.