what is this thing called 'geometry'?
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2manyoranges
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TootyR this one is interesting...'...Your also right, modern bikes are not for xc peddling....they are for throwing down a hill, so im not surprised that the geometry is completely arse about face to a early 90s mtb'.
Your are right about a certain period, but my experience in the last year has been very different...
You are right in respect of many 'progressive geometry' frames and bikes from 2010-20. There was a lot of attention to head angles during that time, and more travel was piled on the front, using slacker and slacker angles - going from 70-69 as far as 63 degrees unsagged. On these bikes, I had to bail from climbing on well-known slopes which I would have 'made' on my 1990s hardtails. The main problem was radically-wandering front end and no way of readily finding a sweet spot between front end control and back end traction.
BUT
Then it seemed that good designers put their mind to the back end of bikes as well as the front end - ie considering the interaction of all the elements of a frame. In 2020-21 there has been a lot of good stuff going on. Transition - (west coast Canada) - introduced SBG (Speed Balanced Geometry) - which required small offset forks (typically 43-44mm), a steep seat angle (75ish), slack front (65 sagged), short stems (35mm) and rangy reach (450mm for me). For sure this was belting when pointed down, but also allowed really competent uphill cranking - the slopes on which I was bailing using pre-20 progressive biked suddenly became a breeze. No wandering front, plenty of rear traction - and a large sweet spot to stand or sit in when climbing. Likewise the Stanton Switch29er, which I have riding a lot recently. My brace of progressive bikes from the pre-20 era struggled to be convincing climbers. The Transitions and Stanton are a deep contrast to this...they climb. Oh how they climb. The short fork offset is a major factor in taming wandering front end combined with steep seat angles and the curved seattube allows tight rear triangles which give huge grip. In fact some climbs just/barely possible on 1990s frames suddenly became entirely do-able, particularly rooty rooty rock step climbs. And of course these bikes wake up when pointed downhill. OK you might say....but I wouldn't ride these on all-day distance-fests. The Transitions are FS, and not really distance-munchers, but the Stanton is really up for it and a bike I would reach for if I was doing a 100-miler.
In my view
The early mtbs were fun...but very limited (my Dawes Ranger was huge fun...but frightening at anything above walking pace)
The 1980-and 90s saw some really thoughtful geometry (Kona, Marin Teams) which worked...really well...and pushed performance
The 2000s saw a lot of innovation which made bikes good at one thing
But today we see highly mature geometry which is yielding some stunning all-rounders
The view from 1990 - I want an Explosiv since it is a great innovation in geometry
The view from 2015 - I want an Explosiv since it is one of the best performing retro-bikes and cheap
The view from 2020 - I want an Explosiv since it's one of the best performing retro-bikes but I can barely afford it
The view from 2025 - A Stanton 29er ti will be in the future be regarded as a brilliant retrobike, alongside things like Explosivs
The view from 2035 - I want either a Stanton 29er ti or an Explosiv - they both are brilliant retro-bikes
Your are right about a certain period, but my experience in the last year has been very different...
You are right in respect of many 'progressive geometry' frames and bikes from 2010-20. There was a lot of attention to head angles during that time, and more travel was piled on the front, using slacker and slacker angles - going from 70-69 as far as 63 degrees unsagged. On these bikes, I had to bail from climbing on well-known slopes which I would have 'made' on my 1990s hardtails. The main problem was radically-wandering front end and no way of readily finding a sweet spot between front end control and back end traction.
BUT
Then it seemed that good designers put their mind to the back end of bikes as well as the front end - ie considering the interaction of all the elements of a frame. In 2020-21 there has been a lot of good stuff going on. Transition - (west coast Canada) - introduced SBG (Speed Balanced Geometry) - which required small offset forks (typically 43-44mm), a steep seat angle (75ish), slack front (65 sagged), short stems (35mm) and rangy reach (450mm for me). For sure this was belting when pointed down, but also allowed really competent uphill cranking - the slopes on which I was bailing using pre-20 progressive biked suddenly became a breeze. No wandering front, plenty of rear traction - and a large sweet spot to stand or sit in when climbing. Likewise the Stanton Switch29er, which I have riding a lot recently. My brace of progressive bikes from the pre-20 era struggled to be convincing climbers. The Transitions and Stanton are a deep contrast to this...they climb. Oh how they climb. The short fork offset is a major factor in taming wandering front end combined with steep seat angles and the curved seattube allows tight rear triangles which give huge grip. In fact some climbs just/barely possible on 1990s frames suddenly became entirely do-able, particularly rooty rooty rock step climbs. And of course these bikes wake up when pointed downhill. OK you might say....but I wouldn't ride these on all-day distance-fests. The Transitions are FS, and not really distance-munchers, but the Stanton is really up for it and a bike I would reach for if I was doing a 100-miler.
In my view
The early mtbs were fun...but very limited (my Dawes Ranger was huge fun...but frightening at anything above walking pace)
The 1980-and 90s saw some really thoughtful geometry (Kona, Marin Teams) which worked...really well...and pushed performance
The 2000s saw a lot of innovation which made bikes good at one thing
But today we see highly mature geometry which is yielding some stunning all-rounders
The view from 1990 - I want an Explosiv since it is a great innovation in geometry
The view from 2015 - I want an Explosiv since it is one of the best performing retro-bikes and cheap
The view from 2020 - I want an Explosiv since it's one of the best performing retro-bikes but I can barely afford it
The view from 2025 - A Stanton 29er ti will be in the future be regarded as a brilliant retrobike, alongside things like Explosivs
The view from 2035 - I want either a Stanton 29er ti or an Explosiv - they both are brilliant retro-bikes
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Just a small note
The Dawes Ranger was always terrible and should not be seen as an innovative bicycle. Its geometry was/ is just awful.
The 'Kona geometry' that you love appeared before long before Kona came into being, it appeared as early as 1984 from other manufacturers, even a certain UK builder had frames as early as 1986.
The availability of materials dictated what a bicycle looked like. Lugs and dropouts could only be had in certain sizes and angles. Tubing was limited so builders had to improvise and be expensive or custom mill everything - and be expensive
Unless you were joining things in aluminium of course, then you could do pretty much what you wanted - and be expensive
As soon as better suited materials and parts were made available all hell broke loose and it all exploded into the flouro madness that we remember.
The Dawes Ranger was always terrible and should not be seen as an innovative bicycle. Its geometry was/ is just awful.
The 'Kona geometry' that you love appeared before long before Kona came into being, it appeared as early as 1984 from other manufacturers, even a certain UK builder had frames as early as 1986.
The availability of materials dictated what a bicycle looked like. Lugs and dropouts could only be had in certain sizes and angles. Tubing was limited so builders had to improvise and be expensive or custom mill everything - and be expensive
Unless you were joining things in aluminium of course, then you could do pretty much what you wanted - and be expensive
As soon as better suited materials and parts were made available all hell broke loose and it all exploded into the flouro madness that we remember.
2manyoranges
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yep on all counts ... yep the Ranger was awful - but even then it seemed a step up from the gas pipe bikes we had ridden off road in the early and mid 70s.
Yep re timeline - I think I mentioned the 1980s-90s being the time of much innovation in geometry. Kona just sticks in the mind as a mass offering from basic through to high level models. Were you thinking of the early work of Joe Breeze and Charlie Cunningham or others?
Yep re limitations of lugs and tube sets - and indeed still an issue - Cy Turner just couldn't get the lengths in Reynolds tubing to do the early Souls and indeed the various iterations and prototypes in the last two decades....
Yep re timeline - I think I mentioned the 1980s-90s being the time of much innovation in geometry. Kona just sticks in the mind as a mass offering from basic through to high level models. Were you thinking of the early work of Joe Breeze and Charlie Cunningham or others?
Yep re limitations of lugs and tube sets - and indeed still an issue - Cy Turner just couldn't get the lengths in Reynolds tubing to do the early Souls and indeed the various iterations and prototypes in the last two decades....
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2manyoranges
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Blimey - and stainless steel. You probably know that they are uncommon since there are differences in SS welding and the tubes are thinner, placing demands on the fabricator - see https://www.donard.cc/blog/stainless-steel-bikes-which-material-is-best. But that’s a loverley thang.
Yup. Not common. They also did some road bikes and a CX too that survived much better. No wheel flop with this one.
Steepish head-tube, slacker seat-tube, short wheel base (I don't think they even bothered with a chain-stay bridge). I reckon on the
right stretch of fast flowing narrow off-road with more modern rubber, the right rigid fork, flat bars cut to 540mm it would literally be like
sitting on a thrilling missile without a point and shoot feel to it; probably a niche between and knock the socks off any modern
29er MTB and Gravel bike.
Definitely would be interesting with hours of fun dialling it in to find that sweet spot balance of front vs. rear weight.
Steepish head-tube, slacker seat-tube, short wheel base (I don't think they even bothered with a chain-stay bridge). I reckon on the
right stretch of fast flowing narrow off-road with more modern rubber, the right rigid fork, flat bars cut to 540mm it would literally be like
sitting on a thrilling missile without a point and shoot feel to it; probably a niche between and knock the socks off any modern
29er MTB and Gravel bike.
Definitely would be interesting with hours of fun dialling it in to find that sweet spot balance of front vs. rear weight.
Wow.
And here I was thinking FINALLY, they started making good MOUNTAIN bikes.
I have been riding the lakes since the 1990s on all manner of bikes.
I can ride further up Helvellyn on my Bird AM9 than I been able to on any other bike, and more importantly get down it all at decent pace too.
It has the perfect gear spread of 30 chainring and 11-51 cassette.
If you like riding in the mountains there has never been a better time to be alive.
And here I was thinking FINALLY, they started making good MOUNTAIN bikes.
I have been riding the lakes since the 1990s on all manner of bikes.
I can ride further up Helvellyn on my Bird AM9 than I been able to on any other bike, and more importantly get down it all at decent pace too.
It has the perfect gear spread of 30 chainring and 11-51 cassette.
If you like riding in the mountains there has never been a better time to be alive.
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