So it's OK for a teacher to hit a kid in this way?

No. But it's reasonable for the teacher to use evidence showing that he was under extreme – and planned and filmed – systematic provocation. Which meant that in this case the jury decided that he was not guilty of the crimes with which he was charged.

It still means he's unlikely to work as a teacher again and, as before the incident, he's got a whole load of stress-related and anger-related problems to deal with. But he hasn't got to deal with them in jail.

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Wrong forum? [mod: moved]

Still, hooray for common sense and realising that "innocent young people", just like grown-ups, can have the collective personality of a psychotic. (Can't remember whose psychological principle this is but he basically reasoned that when you get lots of people in a group their sense of individual responsibility and morality diminishes and their aggressiveness, cunning and criminality may increase – e.g. riots, looting and mob violence)

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I haven't got that set, but I have got an excellent Halfords Professional socket set. The Professional range is a bit more expensive, but justifiably so – it's got a lifetime guarantee. If you break stuff, take it back and they'll replace it.

I've worked in several workshops that use Halfords Professional allen key sets, I've got a set myself, and they're superb quality. I haven't used my socket set anywhere enough to judge its durability but it feels solid, it's well-machined and it's a precise fit so it inspires confidence.

I'd try and avoid cheap tools if possible.

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Someone will no doubt correct me if I'm wrong, but I think copperslip is used because it's got a very high melting point. If you use bog standard grease, there's a chance that the high temperatures (that brake pads reach) could make the grease start to melt, turning it into oil which then runs down the back of the pad and soaks into the bottom of the pad or goes onto the disc.

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Surely not! NOTHING is rideable on one of those! You'll DIE!

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Maybe keep them in the freezer? GCSE biology coming in here.

Surely that will just preserve the bacteria and prevent them growing. Freezing doesn't kill bacteria, AFAIK.

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How much weight would you save with 24 spoke wheels? I'd suggest that unless you're a top-level racer, you'd probably be better off going with 32s as they are more likely to last longer.

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Now that's not a bad attempt at one way of testing how bearing seals will resist the ingress of water. I think it's deeply flawed but credit to kaesae he's making an effort to do something scientific, i.e. objectively repeatable and verifiable.

I think the major flaw is that it doesn't adequately recreate the sort of conditions bearings tend to be subjected to in real life. In fact the only way (well, the cheapest way) I can think of to test bearings alongside each other in real life situations would be to fit two different sets to a bike.

A symmetrical suspension design would be a good start; I know Specialized supply their dealers with frame prep and bearing pulling/seating kits so something like an Epic would be good, the mechanic could ream and face each mount point in the frame to ensure all fittings are clean and the angles are good. Then, on the drive side of the frame fit Katec bearings and on the non-drive side fit another brand. Granted, this only allows you to compare two kinds at a time, and you would probably have to repeat the test with new bearings and mounted on the opposite sides of the frame in order to ensure that an asymmetrical load through the frame didn't skew the results, but with time and effort this would probably be the best way to actually compare the bearings. It would simply be a matter of seeing which side developed play first, how fast that play developed and what state the bearings were in after prolonged testing.

Just saying, like.

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Ouch – what happened?

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So who knows the score about cables then? Come on, who? ME! That's who!

I have touched expertly serviced more than three literally MILLIONS of cables on bicycles and some people paid me money for it, so I'm a real EXPERT! I know all there is to know about cables, because I've seen some.

I sell highest quality cables. Well, I sell average cables, I mean most of the major cable manufacturers make comparable cables, but I've chosen one brand because they're the best because I say they are. I use galvanised cables because I say they're the best, even though the manufacturers also make stainless steel ones. I disregard all those people who say that stainless steel cables are better or more appropriate because they don't know anything!, not like me, and anyway, they're just trying to make money.

But what's really great is that I lubricate the cables with my own magic man grease! It's REALLY EXPENSIVE, well, it takes me a bit of time and some effort, but it makes a HUGE difference to performance. Because everyone notices the vast difference in high performance cables. Well, I do, because I'm an EXPERT – my hands are so expert-ish I don't need even need tools! Or "science".

Some of you who aren't EXPERTS like me might notice that the cables are not as "smooth-running" or so-called "long-lasting". Well that means nothing. That's because my magic grease actually INCREASES the drag on the cables, but remember I'm an EXPERT, I know what I'm doing. My magic grease means that the cables actually absorb energy – and absorbing energy means a performance increase! No, it does, because I say so. I've made it better!

I won't confuse myself you by explaining, in any kind of specific way, how I have reached this conclusion but suffice to say that I'm the best expert and if you disagree it's clearly because you're an IDIOT.

Now, who wants to buy my cables?

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AFAIK a driver awareness course is only offered to a small portion of people deemed to have "only just" broken the law; I think it's 32-36mph in a 30 zone, or thereabouts, for example. It's based on the assumption that they broke they law mainly because they weren't really concentrating on driving.

Ignoring a red traffic light and driving on through 23 seconds after it's changed is not a minor infringement, it's the action of a complete fool. If he doesn't get banned this time, it sounds like he's likely to in the future…

As for the helmet thing, tell him you can pick them up for about £20 in supermarkets or Halfords. If it's got the CE mark, it will be safe. Doesn't sound like you owe him any favours.

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…you've all serviced hundreds of frames and replaced and analyzed thousands of mountain bike bearings, just like me.

This is also important. Doing something lots of times does not make you an expert on its own. How exactly have you analyzed (sic) those bearings?

As many of the engineers on here will tell you, "feeling" the difference by rotating bearings in your hand is certainly not an objective or scientific analysis, regardless of your claims of expertise.

Do you have any measure of degree of play in the bearings, an analysis of the amount of contamination, an indication of how much the seals have been compromised, a measure of bearing surface corrosion compared to force damage (denting, grooving, brinelling), etc.? What sort of records of bearing types do you keep and how have you analysed the new bearings from each manufacturer? What degree of variability is there in the output from each manufacturer or each product line? How often do you qualitatively test a sample of each new bearing and what percentage fall below your standards? What are your standards and why have you chosen them?

A good engineering company will have quantifiable answers (that means answers with a number) to most of the above questions; unless they are tied to one manufacturer, many companies seeking the best quality components will be constantly researching the market, testing and comparing products. And they will assert expertise by describing their research methods and findings.

"I'm the best because I say I am and I know a lot" is the pathetic cry of an amateur.

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OK what kind of grease is it that you use?

We know this one. It's "incredibly expensive grease", according to his eBay pages.

Or £80 for 4kg, according to his post on p6, which by his own admission serves a lot of bearings. Which is not particularly expensive for a specialist grease.

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You want proof I state again. The length of time that they last!

I think you're confusing proof with "because I say so."

What's the main reason people change their bearings? Because their old ones have developed play. What's likely to cause play in bearings? Not dirt or water, but impact abrasion of the balls and bearing surfaces. Which is better at resisting impact abrasion? Full complement bearings.

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If you take it to a shop they'll have the right tools to re-cut the thread so you'll know that the threads there are in the right place. Half an inch isn't _too_ bad (although it's not wonderful), you could usually get away with just fitting a normal BB anyway, maybe with PTFE (plumbers') tape in the dodgy bit but it's best to get it checked out with the proper tools.

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I've got a couple of technical tops that are pretty much beyond hope, but they're both over eight years old.

I haven't dared nuke them on a 90 degree wash, but I've generally found that soaking them, and others, in bio washing powder (and 40 degree water) for a while does a pretty good job of stopping them being smelly. My washing machine has a "soak" button where you can basically pause one section of the wash cycle for anything up to about four hours to allow the washing to soak in the soap solution – I've found that helps but of course you can always just use a bowl of water and powder.

That said, merino really is pretty good at not smelling like old technical tops. It smells a bit like merino (the eternal reek of damp wool ; ), but that's not as offensive a smell!

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Holy cow, this thing is still going… well done bassspine, that xkcd frame came to mind when I wrote my long ranty answer.

Now, I'm a scientist first; I think if something is trustworthy then it is objectively verifiable and repeatable. This is why I completely distrust anecdotal evidence, especially from people trying to sell something. Ben Goldacre's excellent book "Bad Science" gives a great account of this that's accessible to anyone even with no knowledge of scientific principles.

I don't claim to be an expert. I'm pretty good at what I do, admittedly only by the testimonies of my customers, but if I'm wrong about something then I'd rather use it as a learning experience than dig in and personally attack my critics. But I would say I've got a modicum of common sense and am able to apply what learning and experience I have in a practical way to new problems.

…which is why I, and curly68 who clearly knows a lot about motocross bikes (whose technology has a heavy cross-over with mountain bikes), and cynic-al, and probably many others, are still waiting for something concrete, methodically explained, or even just vaguely intelligible, by way of an explanation why kaesae think he "knows the score" about bearings.

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So, while we're at it, you've told us you sell cheap caged bearings which you take apart and re-grease with your own magic formula. These bearings are primarily pivot bearings, although you don't ride them yourself.

Given that pivot bearings are mainly load-bearing rather than rotational, the tolerances of the bearings themselves is not an issue – tight tolerances, ceramic bearings etc. are for high speed efficiency – so using bearings with relatively low tolerances is not a huge problem, especially as the bearings don't even make a full rotation, probably not even half.

What puzzles me is why you are trying to convince us that using caged bearings for pivots is a good idea, when caged bearings have fewer balls so the loads are effectively higher on each individual ball. A full complement bearing would share the load over more balls. This would mean that, disregarding all other factors, caged bearings would not be as long-lived as full complement bearings when used for pivots.

Also, others have suggested that the only reason caged bearings are more resilient to dirt and grit is because there is more space between the balls; the grease becomes contaminated with dirt and grit as usual but because there is a higher concentration of grease to balls, the grease effectively harbours the dirt so less comes into contact with the balls. The cages themselves do not prevent dirt coming into contact with the balls, in fact they present more of a consistent surface to the ball which could become contaminated with dirt (compared to an adjacent ball in a full complement bearing). The seals may prevent ingress of dirt and / or water, but you've told us that you replace the original seals, which at best maintains only their original integrity but also carries a risk of damaging the seals (albeit only slightly) when removing and replacing them.

So in simple terms, that's why I don't think you've presented a particularly compelling argument. And also I think I've given a better account of myself than trying to quote anecdotal evidence or data I've gathered myself. And I'm not even a qualified engineer, just an experienced professional bike mechanic with a science degree. I'm sure an actual bearings engineer will be able to provide better scrutiny, and preferably one who's not trying to sell us something.

And "farts with his face?"… please.

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I find bearings, especially pivot bearings, are a bit like cables – sad people spend far too much time obsessing over them when they should be riding their bikes. The rest of us lube stuff, fit it properly and replace it when it's worn out.

I'm certainly not going to try and correct a troll who doesn't even have a consistent argument and is just trying to use a forum about mountain biking as free publicity.

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and FWIW I've used these guys a few times and found their bearings great:
http://simplybearings.co.uk/shop/

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You'll probably have to wait until Monday to phone them and find out…

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did you mean…
?

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Well said! And that's starting to make sense. But otherwise, cheap bearings are still cheap bearings, even if they've got more space around them for the cack to hide.

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So, just to get this straight, someone who sells caged bearings is trying to convince us, in purely anecdotal and not particularly verifiable terms, that having small fragments of metal in between the balls (though not completely surrounding the balls) somehow prevents the ingress of dirt and water, and not only that but having fewer balls to share the bearing load is in some way a good thing that increases the life of the bearing?

…

No thanks.

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If it's a genuine Veho Muvi then it doesn't put the timestamp on the video. If it's a cheap Chinese knock-off then it will, and it will film at 720×480 instead of 640×480. Not a big deal, but the quality isn't as good and it will fill up the memory card faster. IME.

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ah, the Chinese bearings one – I get it! Sorry for being so slow. And yes, I did think you were babbling like a mental person. ;) Mind you, on this thread you wouldn't be the first…

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I tend to agree with myheadsashed – unless you're racing and the course is cleared, or you've already checked out your run and you have mates spotting it for you, you should always ride as if there might be a horse, dog-walker or felled tree just round the next corner.

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This is turning into a very amusing thread. Please continue feeding the troll…

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Mine came with a 100mm stem, I used the "oft quoted rule of thumb" above and fitted a Thomson 120mm stem and now it feels spot on.

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I had two of those emails. Logged in to PayPal (by typing in the address rather than clicking on a link) and all my details were unchanged and the account was still there. No idea what was going on but haven't had any problems since.

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I've got a couple of Surly Singleators, I've used DMR Tension Seekers and something akin to your first photo in the past.

The Singleator is great and allows you to run in "push up" rather than "pull down" position too, which increases chain wrap around the sprocket (or freewheel), which should help prevent your chain jumping under load.

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http://www.petracycles.co.uk/product_info.php?language=en&currency=GBP&products_id=17246&source=googlepbs

lousy pic but you get the gist.

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Yes, but for pity's sake use a proper shim instead of four thicknesses of inner tube to twang around inside. Easton do them, and so do others.

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Hadn't been near the site for a while then met some familiar faces at SSEC and logged on. I remember I used to post absolutely loads while I was a student (2002/2003ish?) then even more when I was paid to sit at a computer all day and pretend to be busy. Now I'm self-employed I can rarely justify the time… although I've been too tempted over the last couple of days.

That said, if it wasn't for GoFar, the mag and the STW forum I would probably have ridden a lot less, would only own one bike and, more importantly, wouldn't be working with bicycles!

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P.S. Met 42 a few times before all *that* happened, on London Critical Masses. He seemed OK if a little odd. I remember the photos that then appeared!

I've got a lovely old Holdsworth road bike that I inherited. It's pretty much all stock 1950s stuff carefully chosen at the time to be the best stuff to race on, then it sat unused in my great uncle's garage and now it's sitting in my cellar. I can't bring myself to sell it but I'll never get round to cleaning and polishing the patina off it to properly restore it.

But it's still nice to look at every now and then.

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This is the time to give the bike a really thorough clean. Wash it in warm soapy water (best not to use washing up liquid, use car shampoo and rinse it off thoroughly – don't jet wash!). Get in all the nooks and crannies and look for ripples, cracks, dents and other problems. If it's a springy bike, check around each pivot and make sure there are no cracks or ripples. Check the forks are straight and the stantions aren't scratched; hold the bike upright and look "through" it from behind to make sure the wheels line up exactly.

Check your levers for bends and cracks and take your seatpost out and check that. Make sure your wheels are still running straight and look carefully at the cranks and the areas around where the pedals attach. Look carefully along your bars and near the point where they enter the stem. If you're feeling really fastidious, take your grips off and check the ends of your bars.

If all of the above is fine, chances are the bike is probably all right. And you've cleaned it, checked it and shown it some love ready for the next time you ride. If there are any problems, head down to your LBS and get it checked over by a _good_ mechanic. (don't just ask on here, amid the good advice you'll get fifteen numpties saying "I rode my Heckler with a cracked frame for eight years and it was all right…" ;))

As for the helmet, again check it carefully for scratches and dents. If in doubt, replace it – some helmet manufacturers have a crash replacement scheme where you send your old helmet back, they use it for R&D and give you a discount on a new one. Unlike motorbike helmets, bicycle helmets can be dropped on the floor and battered a bit and the plastic shell usually prevents the impact-absorbing polystyrene getting damaged too much.

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http://www.ison-distribution.com/ison/english/product.php?part=SCPPRM2K

not expensive, ask your friendly LBS to order one for you. Or I think Madison do one too (as M:Part) for around the same price – under a tenner.

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I've got a Vango Equinox 250 and it's utterly excellent. However if you want more space I'd go for the 450. They are superbly made, very quick and easy to put up and bring down, the quality of the materials and construction are very good.

With tents, like many other things, you do get what you pay for. It may be worth looking for a second-hand one on eBay; growing families sometimes sell of perfectly good tents. If you pick one up, clean it thoroughly and get hold of a couple of bottles of Nikwax Solar Proof (I think that's what it's called) – waterproofing and UV-proofing stuff, restores tent materials.

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That's a YouGov / The Sun poll – it's worth remembering who The Sun's in bed with anyway…

Is anyone else tired of Alex Salmond whining away? He gets his turn, the nationally-broadcast debates cover the three parties common to everyone.

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Mavic generally make good rims. The higher-end ones build well and their braking surfaces are well machined and even (irrelevant to you if you have disc brakes, but convenient for the builder).

"Any thoughts on mavic rims" is a bit like "Any thoughts on Trek bikes" – what sort of rim was it and what do you use it for?

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