Search found 131 matches

by StephenW
17 Oct 2019, 2:43pm
Forum: Bikes & Bits – Technical section
Topic: Small wheel blowouts - options?
Replies: 96
Views: 2102

Re: Small wheel blowouts - options?

An old french cycling guide recommends tying a branch behind the bike to keep the speed down on downhills. If a forester asks where you got it from, you should say that you brought it with you from Paris. Anyway... The Sturmey Archer dynamo is a bit inefficient according to lab tests. This will be e...
by StephenW
30 Sep 2019, 8:54pm
Forum: Bikes & Bits – Technical section
Topic: Anyone using an 11-speed 11-42t (or similar) with a triple chainset?
Replies: 64
Views: 2477

Re: Anyone using an 11-speed 11-42t (or similar) with a triple chainset?

The only way I could see it as a viable option is if you modded the rear derailleur cage so the overall range is somewhere around 65 teeth, then would you get a simple sistem with all the gears usable Perhaps you could have a sprung return idler that helps to take up the slack in addition to the re...
by StephenW
28 Aug 2019, 3:42pm
Forum: Bikes & Bits – Technical section
Topic: Forks on backwards
Replies: 54
Views: 2289

Re: Forks on backwards

Hi MickF I know what you're getting at, but I don't think the position of the dropouts matters much. What matters is the position of the contact patch. In both of the cases you describe, the contact patch will move to the right when you steer left. With the forks reversed it will move further right ...
by StephenW
23 Aug 2019, 12:53pm
Forum: Bikes & Bits – Technical section
Topic: Forks on backwards
Replies: 54
Views: 2289

Re: Forks on backwards

Some boffins have produced a mathematical model of bike stability called jbike6. It runs in Matlab and can be downloaded for free. Two important outputs which it gives are the weave speed and the capsize speed. The weave speed is the speed at which the oscillations become smaller and smaller when th...
by StephenW
21 Aug 2019, 10:51pm
Forum: Non-standard, Human Powered Vehicles
Topic: Nazca Fuego rack fitting
Replies: 6
Views: 4871

Re: Nazca Fuego rack fitting

Problem solved! Nazca replied very quickly. I poured boiling water over the tube which the bolts are screwed into, to soften the loctite. After that I was able to grip the tube with pliers to stop it spinning, and unscrew the other bolt. Nevertheless, I do think it is an odd design.
by StephenW
21 Aug 2019, 3:21pm
Forum: Non-standard, Human Powered Vehicles
Topic: Nazca Fuego rack fitting
Replies: 6
Views: 4871

Re: Nazca Fuego rack fitting

I'm trying to remove the underseat rack from my Gaucho (don't need it on at the moment), but am running into difficulties! I have got one of the main front bolts out (the right one), but the other one is still screwed into the nut which is inside the frame. This nut is spinning around when I try to ...
by StephenW
11 Jul 2019, 11:33am
Forum: Bikes & Bits – Technical section
Topic: Six bolt adapters for centrelock hubs
Replies: 28
Views: 969

Re: Six bolt adapters for centrelock hubs

A quick google tells me that Araldite has a shear strength of about 2500 psi. At a very rough guess, the surface area of the splines might be 2 sq. inches. A strength of 5000 pounds seems like plenty? The rotor would be utterly destroyed before you could apply a lateral force that high I think. I co...
by StephenW
10 Jul 2019, 10:54am
Forum: Bikes & Bits – Technical section
Topic: Six bolt adapters for centrelock hubs
Replies: 28
Views: 969

Re: Six bolt adapters for centrelock hubs

The lockring gets in the way. Yes, this is the problem. I got the adapter partly so that I could take the disc off using only a torx key. This could be useful when taking the bike on a plane. I wouldn't want to rely on a disc of mine solely held on to the hub by epoxy. Well, the splines should be t...
by StephenW
9 Jul 2019, 8:30pm
Forum: Bikes & Bits – Technical section
Topic: Six bolt adapters for centrelock hubs
Replies: 28
Views: 969

Re: Six bolt adapters for centrelock hubs

Would it be OK to glue the adapter onto the hub with epoxy? Then it would be possible to dispense with the lockring. This would allow the disc to be removed using only a torx key, without needing the special lockring spanner.
by StephenW
26 Jun 2019, 12:31pm
Forum: Campaigning & Public Policy
Topic: Cyclist 50% to blame for hitting pedestrian
Replies: 199
Views: 14104

Re: Cyclist 50% to blame for hitting pedestrian

I think it is worth considering the environment* in which this happened. I'd like to consider two aspects. Firstly, as I understand it, this is a junction in central London which is busy with pedestrians and motor vehicles, yet no green man is provided. This is pretty useless IMO! I think it is like...
by StephenW
6 May 2019, 12:48pm
Forum: Bikes & Bits – Technical section
Topic: the art of bicycle folding/packing for transport; modifications for rinko etc.
Replies: 77
Views: 3162

Re: the art of bicycle folding/packing for transport; modifications for rinko etc.

The Rinko idea seems quite nice, although I'm not sure about regularly taking the headset apart. I feel like a headset, especially a threaded one, is the kind of thing you want to get set right, and then leave alone as much as possible? I thought this video might be of interest to some (it's a foldi...
by StephenW
30 Apr 2019, 9:57pm
Forum: Campaigning & Public Policy
Topic: Painted cycle lanes may make roads more dangerous for bike riders
Replies: 117
Views: 5000

Re: Painted cycle lanes may make roads more dangerous for bike riders

Well, I can see that there are some potential issues with surveys. However, if we reject all surveys out of hand, what are we left with? How do we find out what the main barriers to more cycling are? Intuition? Anecdote? Poking a finger in the air? Surely the thing to do is to look at each study in ...
by StephenW
27 Apr 2019, 5:18pm
Forum: Campaigning & Public Policy
Topic: Painted cycle lanes may make roads more dangerous for bike riders
Replies: 117
Views: 5000

Re: Painted cycle lanes may make roads more dangerous for bike riders

Certainly the car has replaced a bicycle as the main mode of travel to work, shop or pleasure ground. This is due to many reasons - many. Those reasons may include "lack of cycling infrastructure" but that will be a teen-weeny reason compared to ... There may indeed be many different reas...
by StephenW
27 Apr 2019, 4:57pm
Forum: Campaigning & Public Policy
Topic: Painted cycle lanes may make roads more dangerous for bike riders
Replies: 117
Views: 5000

Re: Painted cycle lanes may make roads more dangerous for bike riders

Quite - so exactly what I said. No, not exactly! There is an important distinction between ...assuming unsegregated roads correspond to whichever performs worse. and what Schepers et al (2011) actually did. If you have another look at my post then this will hopefully become clear. To be clear, I'm ...
by StephenW
22 Apr 2019, 12:45pm
Forum: Campaigning & Public Policy
Topic: Painted cycle lanes may make roads more dangerous for bike riders
Replies: 117
Views: 5000

Re: Painted cycle lanes may make roads more dangerous for bike riders

Cars in London (and other urban spots) cause high levels of pollution, as well as squashing and maiming many pedestrians, cylists and, of course, the car drivers themselves. A superhighway does very little if it just makes you feel a bit safer - especially if (like the pedestrians) you are still su...