Are we nearly there yet? (More geometry nonsense)

2manyoranges

Old School Grand Master
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I know that 10mm here or there, or a couple of degrees over there can make or break a frame. God only knows I have been on almost every permutation of STA, HTA, TT length….

I mentioned in passing that I was surprised how slowly experimentation with geometry has progressed. I ached for longer top tubes in the 90s - and cheered when Joe Murray influenced Marin design as well as pushing tt length in Konas. And I welcomed Gary F’s experimentation with the front end of bikes in his Genesis Gen1. But it was all so slow and painful. And it still is. Why so slow? We know enough about geometry to do all the theory and the empirical testing. After all, over in Chemistry, Bernie Bulkin (great name) has essentially said ‘well…we’ve done chemistry now (apart from bits of catalysis) and the theory is nailed … now it’s just about seeing what happens when we put x with z….’. And geometry is the same. There was nothing in the tubes which prevented messing with bonkers angles in the 1920s, and the same remains true today. Of course, if you manufacture forks somewhere other than you manufacture frames, you get ‘geometry lock in’ - you are stuck with you frame angles since you rely on a specific supplier of a specific fork length, rake, trail etc.

The performance of a frame is indeed highly related to the sum of the parts, each making its own contribution and each needing optimisation in relation to the other.

But it STILL is so sloOooooooow…..

Well done Joe M for the additional 15mm on his steel and Ti bikes of the 90s. Well done Gary F. Well done Mondraker for ‘forward geometry’ and Transition for SBG….(steep seat angles, slack HTAs and reduced offset) … and Stanton and Cotic and Bird and Shand in the UK - but grief that’s THIRTY YEARS of torching.…Darwin saw moths changing their colour more swiftly than that….

Are we nearly there yet? Probably….but it‘s all soooooooo slooooooOOOOOoooooooooooooooow
 
Well, I'd want to try the Grim Donut for kicks, but I think my '93 Stumpjumper is better for the kind of riding that I do. If I were to design a custom frame or choose a frame based on geometry, it would be similar to a current cross country bike. For a medium, something like 74/67, 440mm reach at 600mm stack, 430mm chainstay. Hmm, just give me a BMC Fourstroke or Twostroke.
 
Ah…on a timed course, Grim Donut six seconds faster than a Commencal DH rig … SIX SECONDS!
Doesn’t go uphill though.
 
A change to geometry driven not by what we need and more my what the industry needs in order to sell more.
The latest. the greatest. The changes that make you want it more than what you've got. We see it with changes to standards, we see it with what the pros are riding and we see it claims given in percentage gain rather than in real world figures.

Are we done yet? No where near. The day we are done is the day the industry dies.


Yes, that was sceptical and somewhat depressing. No I wont retract it. It isnt just cycling, its everything. We are a consumerism based society and we are doomed.
 
Personally liking these kind of threads.

- If we talk about the development of the safety frame / double triangle, I would guess the begins had more to do with empirical learning, rather than a mathematical sit down at the desktop type of finding.
- It's still being researched the exact reasons how a bicycle balances. Fascinating in a way for a such a mature product.
- More radical departures of known geometry is of course a business risk and the risk is largely off-set by marketing BS and fashion trends;
much of it utter crap, failed experiments, fashion shifts, etc.
- I like very much Joe Murry's input, but he does admit, he didn't really invent anything new that had not been done before.
- Perhaps the limits of geometry acceptability is more related to the human pilot? Which we know hasn't really evolved that much.....
 
NVC - I'm with you with 'everything' ... I despair of the low standard of housing (even when they are obliged to meet current standards, those standards are way too inferior for the planet), the unfixable nature and disposable design of things from razors to dining tables. And the lack of compatibility between the ballooning component standards - BBs, cranks, axles, dropouts etc - is hair-tearing when it leads to things just lying around in boxes. Terrible, as you say. But actually I wonder if the geometry innovation thing is actually the reverse: inhibited by the companies lacking the confidence to be progressive and experimental in frame design. After all, they have to order masses in advance to make money and neither want to have loads they can't sell, or models which seem to invalidate last years' designs (pi+++ing off customers). Mondraker was considered to have pushed the boat out too far (no pun intended) with Forward Geometry, but it sort of paid off for them. SBG caused a real stir of whispers amongst the big boys, who criticised it in public and then went back and changed their own designs without fanfare for the following year. I think that what you have said is not sceptical, it's realistic. And COP26 is utterly failing to confront the issue of transforming economic models. I can't see any premier saying 'Hey...vote for me and my high credential environmental policies - with them we will reach net zero but you will have less choice, more expensive things, travel less and have to eat more expensive food....'. Frankly, I am fine with that but I can see why its electoral suicide and few parties are even vaguely near confronting realities. Meanwhile, I'd like to ride that Ra with the silly-low BB....real ground hugger and pedal-strike city I warrant....but possibly quite interesting....
 
Wheelbases are now too long, IMO. It might make a bike more stable downhill and at speed, but 'stable' doesn't mean it handles well. I'm not finding my new bike that exciting to ride. There is definitely a lot more work to be done on geometry. And suspension damping.
 
Wheelbases are now too long, IMO. It might make a bike more stable downhill and at speed, but 'stable' doesn't mean it handles well. I'm not finding my new bike that exciting to ride. There is definitely a lot more work to be done on geometry. And suspension damping.
Yeah, i owned a couple of mondrakers and both of those were pushing 48-49 inch wheelbases, for someone who likes to hop around it was a pain more than a positive. I've gone back to my NS surge hardtail with it's 46 inch wheelbase and 16.5 inch chainstays, playful but still ploughs through the rough!
 
BB95 the charts are interesting on this in terms of my experience of the Stanton Switch9er and COTIC BfeMax.

As I have mentioned here and in reviews, the Stanton is just BMX-like in singletrack. I am round turns before I consciously have turned the front in. The BfEMax is a little more pedestrian - but a slight movement in style deals with that. The Stanton loves to hop, and the BfEMax takes a bit more body language to get airbourne. Hang on….the Stanton has a wheelbase of 1203mm/47.4 inches, and the BfEMax is SHORTER, at 1186/46.7 even though it feels longer. WTF. AH…the chainstays. The Stanton comes in at 428mm and the COTIC at 444mm.

That’s the measurement which seems to contribute most to the different feel of the bikes re ‘nimbleness’.
 
Wheelbases are now too long, IMO. It might make a bike more stable downhill and at speed, but 'stable' doesn't mean it handles well. I'm not finding my new bike that exciting to ride. There is definitely a lot more work to be done on geometry. And suspension damping.
What is your new bike?….
 
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