When it comes to geometry, Commencal has stayed true to its roots by keeping the bike quite short in comparison to modern trail bikes. Speaking with the guys at Commencal, they say they’ve done this to suit the super steep terrain in Andorra.
Medium 435mm reach (many mediums are around 450mm now for this style bike)
Large 460mm reach
At what gradient does one person's 'downhill' become 'steep downhill' to make this relevant? And why should having a shorter reach help with 'super steep terrain' anyway?
It's an interesting view and I think I've read similar about proper DH bikes being shorter in reach. So will the super long lengths start to come back down in a couple of years as everyone sees the light?
For reference, my own bike from 2015 is a medium and has a 435mm reach, but it was considered quite progressive 3 years ago. Would love a go on something with much more reach to see if it really does make a difference for where I ride (Forest of Dean).
given the standover on most bikes these days size labels are just about irrelevant. You can just about pick your length of bike that suits you.
And why should having a shorter reach help with ‘super steep terrain’ anyway?
I'm not sure it does as a standalone geometry measurement based on the fact that i am almost certain i read an article saying Minnaars V10 had a 500 reach on it. Or may have been a different rider, anyway, having had experience of the very long my tuppance is that it comes down to rider ability and rider preference as to what works best for an individual. That's both unhelpful and a nightmare for manufacturers i would have thought.
<span style="display: inline !important; float: none; background-color: transparent; color: #222222; font-family: 'Open Sans'; font-size: 16px; font-style: normal; font-variant: normal; font-weight: 400; letter-spacing: normal; line-height: 22.4px; orphans: 2; text-align: left; text-decoration: none; text-indent: 0px; text-transform: none; -webkit-text-stroke-width: 0px; white-space: normal; word-spacing: 0px;">having had experience of the very long my tuppance is that it comes down to rider ability and rider preference as to what works best for an individual</span>
Basically, this.
It's good that we have a choice now, and bikes are available for all shapes and sizes. One measurement does not make a bike though IMO.
It isn't just about steep,l it is also the other stuff that comes with it (though not necessarily in the case of DH tracks) - really tight hairpins and narrow trails. For normal mortals, that tends to imply slow speeds.
I was quite liking the slightly longer reach of some of the newer bikes until I popped my shoulder out a few times, it now feels more comfortable with something a bit more conservative. Current bike is a medium with a 435mm reach & 50mm stem.
I did try a bike a with a longer reach and short stem (450mm & 35mm) but found it wanted to tuck on me when cornering but that could just be me not being used to that set up.
Personally, I'm much more confident on my longer Pipedream Moxie (510mm reach) on step terrain than ever before with shorter bikes. I'm now able to go down certain shutes for the first time, and have less wheel lift while climbing.
But that's just me and my preferences. However, implying that shorter bike = better in steep terrain sounded weird in that article
"At what gradient does one person’s ‘downhill’ become ‘steep downhill’ to make this relevant? And why should having a shorter reach help with ‘super steep terrain’ anyway?"
Reach is the horizontal component of BB to top centre of head tube, whilst stack is the vertical component.
If your bike has a reach of 450 and stack of 600 on the flat then the diagonal distance is 750mm at an angle of 53 deg up from the horizontal.
Put the bike on a 10% slope and the diagonal distance is still 750mm but angle changes to ~47deg making the stack now 551 and the reach 508mm. And a 10% gradient isn't steep in MTBing terms.
I've noticed that my fairly long (455 reach and 50mm stem) hardtail feels great on my flatter singletrack (average gradient up to about 10% but a bit long on my steeper DH trails (average gradient 10-20%). My more compact full-sus (425 reach) suit that stuff better. Both bikes are mediums and I'm a long-limbed (thus shorter back) 5'10.5.
I'm 5'11" and am very comfortable riding the very steepest stuff you'll find anywhere on sub 400mm reach bikes. They obviously aren't anywhere near as stable as longer reach bikes but are loads more maneuverable and far easier to lift the front (manual, hop) when pointing downwards and (for me) loads more fun.
IMO Enduro/Strava has brought the need for going faster and requiring stability into a lot of peoples *needs* when choosing new bikes. Enduro stages are generally tackled thinking about times rather than just ridden for fun. The fastest line down a hill is rarely the funnest.
The fastest line down a hill is rarely the funnest
Too true
I thought the general rule was that longer bikes make it harder to weight the front (stack height being equal).
There are plenty of -25-30% gradient trails around us and whilst there's plenty of grip in the dry, I'd take any advantage I could most of the year!
20-30% isn't very steep.
an overly long bike also makes it harder to un-weight the front
I can see a certain logic to it. In theory, the longer the bike the more the front will drop on steep stuff. In practice I've always felt more comfortable going down steep stuff on a longer bike. Maybe I just don't ride stuff that is properly steep though.
If you are talking about extremes, how far behind the front wheel contact point you can get your weight (important for going down steep stuff) is determined largely by your hand position, which is determined by head angle and stem length, also stack and wheel size though the effect of those depends on gradient. How near the rear wheel you can get your weight (important for doing jumpy stuff you wouldn't really be considering if going down really steep stuff) is determined by stem length, reach and chainstay length.