Search found 158 matches

by Urticaria
4 Feb 2015, 1:00am
Forum: Bikes & Bits – Technical section
Topic: New Mechanical Discs Out Yet?
Replies: 46
Views: 14521

Re: New Mechanical Discs Out Yet?

Brucey wrote:I am not an advocate of using magnets as pad retainers on disc brakes that will see a lot of heat for that exact reason. There are very few magnetic materials that will remain strong permanent magnets at temperatures much about 150C. You can get to 150C quite easily.

I would have thought this not accurate. There are strong permanent magnet materials that have a Curie temperature of many, many hundreds of °C. These can still lose their magnetism below this temperature in a processes analogous to creep, however 150°C is roughly the no-creep limit only for the best neodymium magnets, and even then brakes don't spend a long proportion of their life time hot. If a manufacturer were prepared to accept second-best magnet material, there would be no problem with creep at all.
by Urticaria
4 Feb 2015, 12:20am
Forum: On the road
Topic: Anyone not get frozen fingers today
Replies: 27
Views: 4056

Re: Anyone not get frozen fingers today

barbelfisher wrote:I purchased a really nice pair of lobster gloves from Aldi recently

I was poised to write a review of these lobster mitts because I am a bit disappointed with mine. In principle they should be warmer than gloves, but I found that they are very damp at the end of a ride, and require turning inside out (quite a dangerous operation with some multi-layer gloves) to dry. I've experienced this dampness before with other Aldi clothing: it is marked as breathable, but isn't very. I give it the benefit of the doubt each time because I reason that Gore-Tex has been around for +40 years, so the rival technologies should now be at least as good. I should learn my lesson.
by Urticaria
27 Nov 2014, 12:21am
Forum: The Tea Shop
Topic: Apple now the most valuable company on earth
Replies: 25
Views: 2460

Re: Apple now the most valuable company on earth

Don't you think it odd, Horizon, that the most highly valued company relies on style & myth, and a legendary figurehead, rather than substance? And other companies that pioneer fundamental science and engineering are laying off workers, and people, like farmers, who make essential stuff like food can't make a profit? I thought you were a bit lefty. Maybe its all about distracting us or our wanting to be distracted from the awfulness of where we are heading. If you feel like distracting yourself even more, this Youtube clip clip might help.
by Urticaria
2 Oct 2014, 9:38am
Forum: Does anyone know … ?
Topic: How to keep warm.
Replies: 46
Views: 3696

Re: How to keep warm.

Mick's right that the hills can be warmer than the valleys, especially at night. Cold air pools in low spots and on the valley floor, filled by katabatic winds. It can be really noticable in some places...like cycling into a lake.

I'd like to side with Shoogle & Paulatic. The idea of layers has never worked for me when mountain walking, and it doesn't work well when cycling either. It involves a lot of stop-starting, which I hate once I've got going on a ride. Also, like with mountaineering, it requires anticipation of what your body and the weather will be like in a few minutes time; it's the grimmest thing to stop when you are getting cold and to then take off clothing to put something else on, especially in high winds or rain.
The concept behind Buffalo clothing of 'close a zip' or 'put another one on top' seems much better in principle. The problems I have with it is that it can get very soggy, it can be too warm during high exertion even when ventilated, and lastly, in colder weather, exposing bare flesh to the air can be quite painful.
What I'd like to see is cheap impermeable clothing with an air pump for ventilation. This could also be used to regulate body temperature, too, by varying the flow rate.
by Urticaria
18 Sep 2014, 1:22am
Forum: Bikes & Bits – Technical section
Topic: know of a rim with ERD of 539mm?
Replies: 10
Views: 1963

Re: know of a rim with ERD of 539mm?

Brucey wrote:most spokes will happily protrude at least 1mm beyond the nipple.
These won't. The nipples bottom out with the spoke end not quite at the top of the slot. The nipples are 14mm long; I don't know whether this is unusual?
Brucey wrote:Note also that you are in severe danger of spending another £20 on a rim that 'saves you' about £5 or so on spokes
This is a danger to my wallet, but is seems fairly easy to spend 40p per spoke and you yourself have been down on Spokesave spokes and their like.
by Urticaria
16 Sep 2014, 10:34pm
Forum: Bikes & Bits – Technical section
Topic: know of a rim with ERD of 539mm?
Replies: 10
Views: 1963

Re: know of a rim with ERD of 539mm?

Brucey wrote:So if your spoke nipples will go another 1mm, it is a no-brainer, I'd have said.

I'm not sure they will, unfortunately; the spokes were protruding into the nipple slots before I dismantled the wheel, so on that basis, I'd rather plump for a 540 than a 537mm ERD.
by Urticaria
16 Sep 2014, 9:14pm
Forum: Bikes & Bits – Technical section
Topic: know of a rim with ERD of 539mm?
Replies: 10
Views: 1963

Re: know of a rim with ERD of 539mm?

Many thanks for these suggestions. The Exal ML21 looks great, but I'm struggling to get a 32h version, and I would need to fit a rear disc brake to use the very good value DT Swiss 533d rim, so the search continues.
by Urticaria
14 Sep 2014, 9:54pm
Forum: Bikes & Bits – Technical section
Topic: know of a rim with ERD of 539mm?
Replies: 10
Views: 1963

know of a rim with ERD of 539mm?

My MTB rim has developed cracks. It is a Mavic XM719. To keep things cheap, I'd like to relace the wheel using the same hub and spokes, but I don't wan't to purchase another Mavic XM719 rim because I've read of other people with cracking problems.
Has anyone got any recent experience of a rim with a 539mm ERD?
I've looked in the databases, but its hard to get hold of many of the rims from one of the common UK retailers, and it appears manufacturers can change these ERD values from year to year anyway, so it has become a bit of a lottery.
by Urticaria
9 Sep 2014, 1:51am
Forum: Bikes & Bits – Technical section
Topic: threaded headset locknuts
Replies: 1
Views: 273

threaded headset locknuts

Is there any reason why the locknut that accompanies threaded headsets is only partially threaded, or lipped?
I haven't found any example that is fully threaded, yet.
I've got about three inches of steerer protruding so the locknut won't bite down. Could it be dangerous having thread showing, or should I just grind off the top of the nut?
by Urticaria
22 Aug 2014, 1:16am
Forum: On the road
Topic: Panniers vs Courier Bag (Commuting)
Replies: 24
Views: 2679

Re: Panniers vs Courier Bag (Commuting)

You're sampling from the monoculture of touring cyclists. In defence of courier bags: they don't make your back anywhere near as sweaty as a rucksack and they hang lower on your back; taking panniers off when you park up is a right pfaff, and if you leave them on, then you risk them being stolen, or the contents taken; if you wire them on, then you can't take them off; if you walk around with a pannier in each hand, you can't do a lot else; if you cycle through woods panniers can snag, or if you cycle over bumpy grounds then they rattle around. Similarly, you won't find many people on here advocating a front basket, even though they are very practical, and you can reach in as you cycle, and you can just throw stuff in. No, a bar bag and panniers are the correct symbols of belonging.
by Urticaria
20 Aug 2014, 9:41pm
Forum: Touring & Expedition
Topic: My first tour (I didn't make it)
Replies: 93
Views: 11871

Re: My first tour (I didn't make it)

I reckon getting off and pushing is not a good idea and it could even have been the cause of your problems. It twists your upper body for a start, then you apply a load which can cause all sorts of muscular strains and aches.It can get your legs as well; these have adapted to the cycling motion and not the climbing motion. I've a history of talking a lot of nonsense on this forum , but I guess cycling is still more efficient than walking, even if it means twiddling away in bottom gear?
by Urticaria
18 Aug 2014, 2:33am
Forum: Does anyone know … ?
Topic: Hardest UK climb?
Replies: 246
Views: 34983

Re: Hardest UK climb?

gaz wrote:Knatt's Lane up towards Knockmill (BTDTGTTS :wink: ) or the Bridleway ( :shock: looks challenging)?

Please do the bridleway for me, gaz, so I can have the vicarious pleasure. The problem is not gearing, but that my bike tipped up backwards every time despite having my bits on the crossbar and not on the saddle.
gaz wrote:Worst I've ever climbed successfully in Kent is Lad's Hill Path, travelling very light on a 753ATB; I was younger, fitter and somewhat lighter at the time. Current bugbear is the Lower Warren Road by-way, I can just about push the bike up it without stopping.

Good grief. You have some skill.
by Urticaria
16 Aug 2014, 9:02am
Forum: Does anyone know … ?
Topic: Hardest UK climb?
Replies: 246
Views: 34983

Re: Hardest UK climb?

Climbs you can't do must be harder than those you can do. I never managed to quite get to the top of this in the Knatt's Valley, near West Kingsdown despite it being smooth tarmac on the slope and my trying about eight times.
Anyone fancy having a go for me?
by Urticaria
15 Aug 2014, 9:33am
Forum: Bikes & Bits – Technical section
Topic: Who uses derailleur guards?
Replies: 4
Views: 523

Re: Who uses derailleur guards?

They are useful for hub gears with click boxes or toggle chains, and Sram still make one for that purpose, so they can't be totally ineffective, nor a stupid idea, nor exclusively for use on cheap bikes. You do see them on cheap bikes, though, which is kind of odd given every expense is spared.
by Urticaria
15 Aug 2014, 9:21am
Forum: Bikes & Bits – Technical section
Topic: Tubeless tyres?
Replies: 4
Views: 448

Re: Tubeless tyres?

I think MTB riders use them mainly for enhanced traction. It enables running at low pressures without getting pinch flats. The tyre becomes more supply, too, so there might be an improved feel/change of handling/lower C_rr (potentially). Because a sealant is required, such as Slime, there is little or no weight advantage, but mending punctures on the trail becomes less frequent. Those sealants don't tend to work at road tyre pressures, and you would want hard tyres, not soft, so the only advantages remaining for road use are feel of the bike, and maybe efficiency but I couldn't say whether this is worth having. Thinking a bit about it, the efficiency might not be higher because when the liquid in the tyre is forced to shear, it will never give any of that energy back, but when the innertube is forced to flex, it will return some of that energy---but then the power going in to shear the liquid would be less...Hmm.