How straight does a frame been to be?

[531colin]

............
Interesting. I once test rode a Genesis Tour de Fer one time and found it almost impossible to steer ' no-handed' Never an issue on other Touring bikes I've either owned or ridden.

Yes, but I recognise 3 categories of "impossible no hands"
1.. Very stable steering, so the bike goes where its heading and needs lots of effort to turn
2.. the polar opposite....think of somebody winning a race (or stage) crossing the line and with their hands still in the air slalom-ing the photographers and team people .....this requires quick steering, and even quicker reflexes
3.. something off-track....sometimes can be ridden no hands with the saddle under one cheek

I'd add a fourth category; bikes with defective headsets.


Incidentally, do you know what steering geometry Steve Mundie used?

Unfortunately I don’t know. At the time I tried to get him to design a small-wheeler for Spa, but he wasn’t interested.
I think a demountable (?) small- wheeler which handles properly would sell in these days when you can’t count on getting a recognisable bike onto a train.

[pjclinch]

I had a go on one of Steve Mundie's small wheelers https://www.steve-mundie.co.uk/ ....literally went up the road, came back no hands, so it is possible to build a small wheeler that rides well no hands, I guess Moulton and Brompton can't be bothered to find out how to do it.

The easiest bike to ride no-hands I've tried was a Dutch hire bike (quite possibly an OV-fiets). It was nice riding along on a cold day with my hands in my pockets, but it's not really high on my overall list of priorities.
I suspect it's not really on Moulton or Brompton's list of priorities either, for that matter, but also the fact that I, a not-very-good hands free rider, can ride them for a bit no-hands in any case suggests they're not appallingly compromised in that respect.

I do know that no-hands ability varies a lot. My wife is much better at it than me on an identical bike, for example (though I can ride a unicycle a bit and she can't at all). Quite a few folk just can't/won't, so that you rode one of Mundie's easily may say more about you than about how good/bad a Moulton/Brompton is in that respect.

Has it occurred to you that I have ridden Brompton and Moultons?

Certainly, but I doubt you've ridden every permutation of both of them frequently and always checked their no-hands capabilities.
Also, my own experience on many bikes is that notionally identical ones can ride no-hands quite differently according to whether there's a 'p' in the month, what side of bed I got out of that day, and so on.

But back to their designers not being bothered to do anything about what's a non issue for most people... "Doctor! Doctor! It hurts when I do this!"; "Then don't do that".

Pete.

[531colin]

How a particular design of bike rides no hands doesn’t depend on the day of the week or the mood of the rider, it’s a constant and it depends on the design of the bike, and whether a particular example of the bike is straight and properly assembled.
If a design doesn’t ride properly no hands then it doesn’t ride properly at all.
People are prepared to accept poor handling of Brompton because there is no other bike which folds as small.
Other bikes with poor handling survive in the market place for reasons I can’t fathom.

[pwa]

I rode a Brompton regularly for a few months and regarded its twitchy handling as an entertaining challenge. I got used to it. I hated the floppy, springy nature of the frame, though, with nothing to stop the seat post and handlebars springing in relation to each other, and the whole frame twisting under strenuous uphill efforts. For me that was all a compromise too far, and if I couldn't take a better handling bike on a journey I'd rather walk instead. I'd get one purely for utility, if it fitted with my commute, but I'd not get one to enjoy. Maybe lighter riders have less of the springing and twisting.

[PT1029]

"If a design doesn’t ride properly no hands then it doesn’t ride properly at all.
People are prepared to accept poor handling of Brompton because there is no other bike which folds as small.
Other bikes with poor handling survive in the market place for reasons I can’t fathom."

Not sure I agree with this. I would have though riding no hands is also related to how much (or little) trail the bike has. Same again for steering flop
That said, some (if not all - all would undermine my point of course) bikes can ride no handed, here is a video some where of a riderless bike going some distance on its own down hill. I think this gets a mention in Bicycling Science.

Bromptons are twitchy as they have little trail, as a confident/able rider, on a Brompton riding 1 handed (eg while signalling) is a bit of a challenge.
Too much steering flop, and the moment the steering goes off centre, if wants to go even more of centre, not what you want riding no handed.
I write as someone who has had a few (not many) decent bikes over the years. I have never managed to ride no handed.
May be it is a confidence thing, I feel if I sit upright it may well ride no handed, but as I can't reach the bars from that position, I'm not willing the risk to try!

[pjclinch]

How a particular design of bike rides no hands doesn’t depend on the day of the week or the mood of the rider, it’s a constant and it depends on the design of the bike, and whether a particular example of the bike is straight and properly assembled.

The bike is a constant but the rider isn't.
The more experience with a particular setup a rider has the more their riding becomes effectively deterministic, but for things that a rider isn't completely dialled in to it's potentially highly variable. Give me a job like ride my bike to the bakery on a Saturday morning and back and I can say with close to 100% confidence that I can do that no problem, Give me a job like demonstrate a good wheelie and it's probably about 80/20 I'll not do a good job. Ask Chris Hoy to demo a track stand and it's a case of how long have you got, where I'm lucky to break 10 seconds... but I've never practised track stands and it was an important part of his day to day job, so that's not surprising.
And riding no-hands, for me, is something I don't really practise. I'm better at it than I am at wheelies, but how far I can go depends a bit on the bike and a great deal on just how much I'm in the zone that day (very much like my unicycling, I don't practise so I'm not consistent).

And yet despite me not being consistent or great at no-hands riding I can still ride my Moulton no hands for a bit. The new one has more or less the same frame as the old one but the bar set up is different with North Road bars on a long stem, so there's more swing to them then flats on a short stem I was used to. For not-good-no-hands-me that made a significant difference at first but after a few rides I could dial that out and now can ride the new one as well no-hands as the old, but it did take a little time. But that despite being poor at no-hands I can still ride it no-hands suggests it's not fundamentally hopeless for no-hands riding.

If a design doesn’t ride properly no hands then it doesn’t ride properly at all.

That doesn't follow at all unless a designer has set out to make a bike that rides no-handed easily as part of the design objectives. A design "rides properly" if a rider can ride it as it's meant to be ridden (typically with at least one hand on the bars) without undue problems assuming they're used to the bike.
And "assuming they're used to the bike" is important, and quite obvious if one is used to seeing very experienced riders fail to get more than a few pedal strokes on a well handling recumbent the first time they try one.
A recumbent perspective also shows me how small changes to how a rider interacts with a bike can make a big difference. Put me on an HPVel Speedmachine with "scorpion" bars and I'm immediately happy and rock solid. Same bike, but with "hamster" bars I find riding the bike very nervous... and of course it's not the bike, it's me. I know a fellow recumbent rider who finds the opposite: tiller bars he's fine, aeros he has problems dialling in to.

People are prepared to accept poor handling of Brompton because there is no other bike which folds as small.
Other bikes with poor handling survive in the market place for reasons I can’t fathom.

The Brompton doesn't have objectively poor handling. It has poor handling if you e.g. try and ride it as if it's something else... so don't do that! (if your entire riding experience is diamond frame racers that may be easier said than done, of course.) It is rubbish honking up a hill out of the saddle... but having found that I put recumbent practice in to effect, stayed sat down and stopped heaving on the bars and as long as the gears are low enough spin on up. Not fast, but if I was in a hurry I wouldn't be on a Brompton.
I don't fold my Brompton up that often. I'm still fine to ride it around as a general bike. FWIW I've never found it twitchy or unpleasant to ride, in fact the first ride I had I was surprised at how it just did what I wanted/expected. Others have a different experience, but as above that's because people are different and interact with bikes in different ways.

You haven't said directly that you think a Moulton handles poorly, but you have at least inferred you think that's so. Why do I ride a Moulton? Because I really like the way it handles, or at least the way it handles the way I ride, typically with at least one hand on the bars.

While there are deterministic limits to what any given design can do (e.g., you can't U-turn a Galaxy Twin in the same space as a Galaxy) the overall handling of a bike is at least in part determined by the interaction of the rider and the bike. And the reaction to Brompton handling (whether it's "twitchy" or "responsive") is a good illustration of that.

Pete.

[531colin]

……as a confident/able rider, on a Brompton riding 1 handed (eg while signalling) is a bit of a challenge.
…….

……
The Brompton doesn't have objectively poor handling. …..

Sorry, I messed up the quotes there, on my phone.
I just haven’t the determination to go back and do it all again

I have started a new thread asking what should be a simple question… to define decent handling… but I expect we will get mired in excessive verbiage

[pjclinch]

……as a confident/able rider, on a Brompton riding 1 handed (eg while signalling) is a bit of a challenge.
…….

……
The Brompton doesn't have objectively poor handling. …..

Sorry, I messed up the quotes there, on my phone.
I just haven’t the determination to go back and do it all again

I have started a new thread asking what should be a simple question… to define decent handling… but I expect we will get mired in excessive verbiage

I assume that PT1029's problem riding a Brommie one handed is being put up as an example of how they're objectively poor handling, but there's lots of people who have no trouble on them at all. I have never had any issue with Bromptons being wobbly one-handed from my first ride.

I've taught people how to ride from scratch on a Brompton. As a Bikeability Scotland instructor I've lent mine to beginner riders in primary schools where their own bikes have had an issue and by doing nothing other than putting the seat down they've just got on and found it fine. On one occasion a lad was just about to an assessed ride when his pedal fell off, so I lent him the Brom. He'd never been on one before. Despite being a beginner rider having to demonstrate signalling under pressure he had no problems with it.

A rider interacts with their bike to keep it balanced and pointing where they want. If they're used to something quite different then these interactions may not have the intended effect. That's "different", not "broken".

Pete.

[Brucey]

....Unfortunately I don’t know. ........a small- wheeler which handles properly would sell in these days when you can’t count on getting a recognisable bike onto a train.

maybe the steering geometry can be worked out from a good side-on photo?

btw if the rear brake cable is unusually stiff, this can prevent no-hands riding too. Otherwise, a sack of spuds can 'ride no hands' quite well, on a good bike.

[pjclinch]

Otherwise, a sack of spuds can 'ride no hands' quite well, on a good bike.

Up to a point, Lord Copper...

If you position the goalposts such that "good bike" means "has no need for rider steering input to keep going in a straight line" then your sack of spuds might do okay, but given that human riders mostly use the bars and are quite happy to steer their bikes continuously that seems a pretty arbitrary place to put them

Pete.