Cycling UK Forum

Rob Archer wrote:I've recently re-read the book that got me into 'proper' cycle touring: 'Adventure Cycling in Britain', by Tim Hughes (Blandford Press 1978). In the very useful section on gearing, he recommends (on page 35) that gears lower than 30 inches (about 1:1.1) are less desirable, and explains several reasons why - not least the risk of lifting the front wheel on a very steep hill.

I liked Tim Hughes' descriptive writing, but I disagree with him on this technical point.

In a pure steady state (exactly uniform pedalling speed over each rotation of the pedals) the gradient at which the front wheel lifts off the ground is a function of geometry only and is totally independent of gear ratio. For a given bike/rider/load weight distribution, it is a function solely of when the vertical through the centre of gravity first falls behind the rear wheel contact point. You can shift the CofG forward by using front panniers, or by getting out of the saddle and putting more weight on the handlebars, but once you've done that, and established a new weight distribution, the critical gradient again becomes a function of the position of the CofG.

However, in practice, you do not pedal at an exactly even speed. We all (especially, I suggest, uphill) shift the pedal (and hence the bicycle) faster between about 10'0'clock and 4'o'clock than when going over top centre or bottom centre. This means the whole bicycle is accelerating (and then deccelerating) twice each crank revolution. The extra force required to accelerate the bike exerts a turning moment that tends to lift the front wheel. (Imagine that the back wheel were fixed rigid to the ground - tramping on the pedals pulls harder on the top run of the chain, which tends to lift the front of the bike up over the rear wheel.) So under these circumstances, the gradient that the front wheel lifts is less than the gradient set purely by geometry.

So the more smoothly we can pedal, the closer we can approach the gradient limit set by geometry (centre of gravity) alone. And the lower the gear (for a given gradient and speed), the easier it is to pedal more smoothly.

So, if you want to maximise the gradient you can pedal up without lifting the front wheel:
(1) get a bike with long chainstays or other geometric features that move the CofG forward of the rear wheel (you don't see mant tandems lifting front wheels!)
(2) put luggage at the front of the bike rather than the back
(3) get out of the saddle and put more of your weight on the front wheel if that suits your cycling style
but having done all that
(4) fit a lower gear.

thirdcrank wrote:Don't forget that magazines have copy deadlines long before the date of publication and AFAIK the CTC mag is no exception. PK probably wrote that months ago.

Except that according to Phil's OP, the ammendment in question was 2010! Seriously, I don't think PK is particularly to blame, in my own professional life I have more than once restated something I believed to be true without checking whether it was still true. Nonetheless it does appear to be an error, however minor. Actually, I think this just reinforces the OP's astuteness in spotting this change.

Phil_Lee wrote:It has often been mentioned in here (and elsewhere) that the only place that speed limits apply to cycles in in the Royal Parks.
While looking this up for someone who didn't believe it, I found that it appears no longer to be true.

I see that in the December/January issue of Cycle, Paul Kitson asserts (p53) that 20 mph still applies to cyclists in Richmond Park. Either he knows better than this forum ... or, more likely, he hasn't spotted the change that you did Phil.

Friday Night Ride to the Coast, October's Brighton ride, top of Ditchling Beacon just after dawn:


I don't claim any special credit for the photo, after all, there were a hundred of us there all witnessing the same view:



(Don't know who you are, sorry, you just happened to form a useful foreground!)

Out of interest, presumably a motor car being pushed is still a vehicle. I would guess that you don't have a right to push a car along a public footpath. But are all the various motoring offences (one way streets, drunk driving for instance) still applicable to a car being pushed?

thirdcrank wrote: I think you can be assured that if a police officer is in physical danger, colleagues will respond promptly....
The main legal decision I'm aware of, which might give you a bit of reassurance, was a judgment delivered by Lord Denning ...

I think that's exactly the point I was making. Police officers do know that their colleagues will not leave them out on a limb. They know that intellectually but they have also absorbed it subconsciously, because that is the culture they have worked in and observed. Part of what goes to make up that culture is that police probably will devote more effort to investigating crimes committed against fellow police officers, and all I was saying is that I have no problem with that.

Anyway, this is all getting a bit distant from cycling issues.

CJ wrote: To make oneself deliberately inconspicuous would however be perverse, so I do not wear camoflage! But neither will I dress up like a clown for the amusement of the bullies. I try to wear clothes from the brighter end of the range of normal street clothing. For example I choose the red jacket rather than the dark blue one when I will be cycling. So although I reject hi-viz, I do not "make every effort not to be seen". I do make some concessions towards conspicuity. And if we count ourselves as civilised that ought to be more than enough.

But Chris, what do you do when it comes to lights? I would venture a guess that you haven't just fitted minimum BS-meeting lights, I would guess you have significantly brighter latest-generation LED lights. Is that a "concession towards conspicuity", or "making every effort to be seen"?

I, by contrast, do want the police to devote more effort to cases involving fellow police officers.

My reasoning is thus. Someday, any one of us may be in a position where we desperately need a police officer to put their own safety in jeopardy to protect us. I want that police officer to know that every other police officer is going to help them. That if they need to call for urgent assistance, all other officers in the vicinity will drop what they are doing; that if they need an ambulance, their colleagues will close every road necessary to give the ambulance a free run; and if they are the victim of an assault, their colleagues will pull out every stop to track down the perpetrator. It seems to me that only if the officer has that assurance can we as a society reasonably ask them to do the things we do ask them to on our behalf and in order to preserve the civilised society that is in all of our interests.

Of course, ideally, they would pull out every stop to track down every perpetrator. But we all know that ain't going to happen in a world of finite resources. So I will happilly settle for them prioritising the support and protection of their fellow officers.

Here's another analogy (actually it's not an analogy but you know what I mean).

There's a well known paradox when it comes to vaccinations. Viewed in selfish, game-playing terms, your best outcome as an individual is if everyone else gets vaccinated (or has their children vaccinated), so that you benefit from the eradication of the disease in question; but that you personally do not get vaccinated (or have your children vaccinated), so that you are not exposed to whatever risk of side effects there might be.

It seems to me the exact inverse occurs with bright colours/hi viz/bright lights. Your best outcome is if you DO wear bright colours, so that you take advantage of whatever benefit that brings in terms of increased visibility; but everyone else does NOT, so that the twin offsetting effects of "if everyone does it it doesn't stand out anymore" and "it makes motorists think avoiding a collision is our responsibility not theirs" do not kick in.

Tonyf33 wrote: ... it really is that simple ....

No, it's really not that simple. You may very well be right in your views on hi-viz, but if it were simple, this thread and the many others over the years wouldn't exist.

gaz wrote:There is a CTC brieifng doument from 2010 concerning public footpaths.

I am not persuaded by the CTC's treatment of the question of whether you have a right to push a bicycle on a footpath.

They establish that a person pushing a bicycle is a pedestrian not a driver of a vehicle. They then extrapolate to say that pedestrians are allowed to walk on footpaths so you must be allowed to push a bicycle on a footpath. But the right to walk on a footpath cannot extend to all other activities without limit, there must be concept of what is an acceptable thing to do while walking, and what is not because it goes beyond just walking. They do actually allude to this through the judgement on "natural accompaniment". As I understand it, that was a view that the right to walk on a footpath included the right to take something that is a natural accompaniment to walking. Specifically, pushing a pushchair or pram was regarded as a natural accompaniment, but pushing a bicycle was not. The CTC dismiss that as being in Scotland and not relevant in England and Wales. But even if that specific judgement is not relevant, it seems to me the concept is. I would want to argue that pushing a bicycle should be regarded as a natural accompaniment, but I would view that as something that had to be argued rather than just obvious.

CJ wrote:The following rhetorical question is perfectly acceptable in polite society:

Why do cyclists go out on the road at night wearing dark clothing? Don't they realise it can only increase the risk of getting flattened?

But not this:

Why do girls go out to pubs at night wearing short skirts? Don't they realise it can only increase the risk of getting raped?

Discuss.

I'm sure you will

Can I rise to the bait? The two questions are partly analogous but not completely so. The man who decides to rape a girl is making a conscious decision to do so. The reason some of us got so hot under the collar about the "short skirts asking for it" excuse is that it implies men do not have a choice, they are the victims of uncontrollable urges. Clearly men do have urges, but as a society, we need to send a strong message that they still have a choice and we expect them to exercise that choice in the responsible direction.

By contrast, the man who knocks down a cyclist is rarely doing so as a result of an immediate conscious choice. More often, he does so as a result of carelessness, inattention, or misjudgement. By wearing hi-viz, or fitting brighter lights, I am not saying anything directly about his choices, because most times, it is not a deliberate choice that is in question at the time he does or does not hit me. I am taking steps to counter his inattention or carelessness, a concept that doesn't really have an analogy with the girl in the short skirt in the pub.

But of course, the motorist does make a choice, just not (usually) at the point of hitting a cyclist. The choice is made earlier, and is the choice to drive too fast, or to use a mobile phone while driving, or to drive when tired. Cyclists wearing bright coloured clothing does influence that choice, by creating a general climate where motorists feel that responsibility has been shifted away from them (to take care control their dangerous weapon so that it doesn't injure other people) onto more vulnerable road users (to take care to keep out of the way of other people's dangerous weapons).

So I don't think there is a very good direct analogy between an individual cyclist wearing more visible clothing and an individual girl wearing a short skirt. But there is a weaker analogy between the indirect consequences, through contributing to an expectation in general that cyclists should make themselves visible.

By the way, there may well be sections of polite society where the second question is no longer acceptable, and I count that as progress. I'll bet there are plenty of Top Gear-following Daily Mail-reading men who still say that, but perhaps on this forum they don't count as "polite society". But there's one other place where that question is addressed regularly, and that's among us trying-to-be-responsible parents of teenage girls!

horizon wrote:

SHAW8670 wrote:The Horizon uses inferior tubing. The Imperial is similar in it's frame componenets (lugs etc) and tubing, but the difference will be in the geometry.

Older Horizons had the same frame set as the Galaxy. Newer ones had either alu or 520 depending on year.

I bought a Horizon in 1989 which had 500 (not even 501!) tubing when the Galaxy had 531

Some plastic clip-on fairings exactly as you describe were being heavily marketed at last year's Cycle show at Earl's Court, but I don't remember the manufacturer's name.

Cyclamity: I agree with everything you say. But when you say:

cyclamity wrote:Whether he likes it or not, he is the servant of members, not their master.

I think the response is: not for much longer ... because as soon as the CTC converts to a charity, he ceases to be the servant of the members and becomes the servant solely of the Trustees, and the members cease to be the ultimate governing authority of the CTC.