psycholist

So you're admitting to blatant racism as well as saying you go to more trouble to read my posts than you'd have to go to if I wasn't ignored. Brilliant . Incidentally a Masters degree in the UK educates to the same level as a bachelor's degree in Ireland (4 years' work), so the assumption that Irish people are stupid is a dangerous one, especially when you bring academic qualifications into it . And I wasn't 'calling Rowan out', just adding more information. As for the tyre debate - has anyone tried these: http://www.chainreactioncycles.com/Models.aspx?ModelID=12593 - I find them amazing on my XC bikes, really good grip off road for the 70a compound, as well as very durable. The tread blocks are pretty low, so no noticeable squirm on hard surfaces either. Deep mud is all that phases them... There's a DH version as well for back tyre use.

Trying to 'call out'? I'm not familiar with this term - Do explain... Wait a minute - since I'm on his ignore list I can say what I like and he'll never know ...

What you're describing there is the Coulomb friction theory. This is a (Pretty good) approximation to what's really happening (Micro and nanoscale surface interactions). This is the easiest to teach in physics/engineering, but does not necessarily represent what happens in every system, especially with tyres (Where friction coefficients can be greater than 1). If Coulomb friction was correct then fitting wider tyres to a car or changing the tyre pressure (Lengthens/shortens the contact patch) would have no effect on its grip as the normal force and the friction coefficient would remain independent of the contact area. Some more information here: http://en.wikipedia.org/wiki/Friction and here: http://en.wikipedia.org/wiki/Traction_(engineering) To get back on topic, having used Continental tyres on my XC bikes and getting the crap scared out of me numerous times as a result of them sliding off anything damp, I wouldn't put Conti's on a trials bike unless I only rode in the dry.

At least someone's taking responsibility - http://www.bikemagic.com/news/article/mps/uan/6473 And if you think this summer was bad, this is the second summer running in Ireland that sucked hairy, dangly orangutan gnads... It also rained more or less continuously from October to January...

I'd be very surprised if the issue is that the nut is coming loose as you cycle and then the wheel is moving... It's far more likely that the nut just isn't generating enough clamping force to begin with. Not an easy one to sort out without possibly changing to different nuts (Or tightening the ones you have more - they'll probably strip though). Get some snail cams or chain tugs to take the chain tension load rather than relying on friction between the nuts and the frame to do the job.

I used to do this (Sanding disk on a power drill, 60 grit paper), but a grind performs much much better and lasts longer (And takes less time to do).

'I' cross section cranks are great in bending, but cranks also experience twisting as your weight is applied through the pedal rather than directly to the end of the crank. A tubular crank, longer in the axis in which is is bent (Shimano Hollowtech style) is the best shape for optimum stiffness to weight for a crank. It is perfectly true that the holes will have very little effect on the overall stiffness of the crank, but 'I' beams don't resist twisting well at all compared to tubes, they're just easier to make and (useful for trials specifically) they're more impact tolerant... There's a test rig in the university where I work consisting of an I beam concreted into a wall - you can't even feel the deflection in the beam if you hang your whole weight off the end of it, but it's laughably easy to twist the beam (cm of deflection with 10-20kg hung off it) if you apply loads off the beam axis.

Looks great for what it's designed for - I doubt if it'd last very long on a trials bike though - the pickup may be poor too. I'd wait for someone with more dental cover than I have to prove me wrong before risking it myself...

With the steel frame there might be a trade off in terms of rear tyre size vs. chainstay shortness. The CNC'd frames get around this with lots of fancy machining around the BB, but a steel frame of this money won't have those features. The other way of looking at buying a more expensive production frame is that it'll last forever and still be sellable if it's only getting occasional use, so it's not exactly money down the drain and you're getting a guaranteed sorted bike... What's the reliability like on the Merino frames? The price seems a little too low to be trusted - if the frames were that good everyone would be using them (Or the other manufacturers would have dropped their prices lots to stay competitive). Steel fails a lot more safely than Al though (It will creak, flex and rust before failing and fail by bending, so you have loads of warning), so it's not a big worry.

What geometry suits you depends mostly on what sort of moves you like in trials. If you're a fan of spinning, big bunnyhops, street/skate park style riding and manuals, short reach frames will probably suit you better. If you like TGS (Tap, Gap, Sidehop) riding and natural stuff, a longer reach frame with a higher BB will probably suit better. The shorter the chainstays are, the easier it is to lift the bike onto the back wheel, but on a long reach frame it will still feel quite difficult initially, especially for manuals, but the bike will feel very comfortable on the back wheel once you're actually up there. 26" frames have their minimum chainstay length dictated by the wheel size, so 375mm is about as short as they get. The feel of a bike will be dictated to quite a degree by the handlebar/stem choice though (This sets the length of the frame and the perceived BB rise and can completely change the feel of a bike), so if you want to make your bike feel more comfortable at speed and easier to manual, fit risers and a short stem, if you like sidehops and gaps (And natural/competition riding), low handlebars and a longer stem are usually better. What height you are, your body proportions etc. will also come into play. Pretty much any frame with the right rider can do pretty much anything you'd expect from a trials bike, so this is a general rather than a hard and fast set of rules...

To make these, pairs of spokes are twisted around each other where they'd usually just cross. That wheel looks like 2 full twists at each crossing... You really don't want to try a wheel with snowflake lacing and a disk brake, it's definitely not as stable as normal 2, 3 or 4X. This was only done back in the day before disks were anything more than custom items (Which the bike journalists at the time would always say was overkill compared to a good set of cantis) ...

A friend of mine sorted this (More or less) by taking all the washers that sit inside the brake arm and putting them outside it. This will force the brake pad to sit against the brake arm. If you're lucky it will hit the rim acceptably to allow you to brake properly. If not you'll have to put spacers between the brake pad and the brake arm to change the pad angle (The guy I know uses segments of a washer). The more expensive options would be to buy different brakes that accommodate the offset (Not sure if they exist, though some brakes are definitely better than others for not catching your ankles) or get a 4 bolt Magura mount frame and fit these: http://www.onza.com/v2/products/p+a/brakes/005.html with the brake mount set as far out as possible.

I'm a fan of 3X lacing on both sides as unless you have a 36 hole hub 4X lacing causes the spokes to lock in the heads of the spokes beside them, making replacing spokes a pain compared to with 3X as you have to loosen the adjacent spokes to the broken one the fit the new one. In terms of the wheels load carrying ability there shouldn't be much difference (Hence 3X being used more or less everywhere else with 32 hole hubs). Snowflake pattern wheels are of course where it's really at ...

Google for a program called spocalc.xls to calculate your spoke lengths. If the rim/hub aren't in the list already in the file you can measure them and add them to the list. The hub is easy enough to measure with a ruler/calipers, the effective rim diameter can be measured by getting two spokes, which you cut to a known length and screwing spoke nipples to them with the end of the spoke flush with the back of the spoke nipple. Put the spokes through spoke holes directly opposite each other in the rim (The hole to one side of the valve hole will be directly opposite the hole to the opposite side of the rim join) and measure how far apart the spokes are in the middle of the rim, adding this to the combined length of the spokes to get the ERD - if it's an old rim that may not be perfectly round take a few measurements and average them. When you're calculating the spoke length don't forget to specify how many crosses the spokes make for the build you have in mind - the usual default is 3, but a lot of trials wheels are built 4X.

A friend of mine had the ratchet ring in his Echo freehub come loose and spin forward under power - the hub was about 6 months old. The warranty replacement is still going strong, but that hasn't got to the 6 month mark yet.

Loctite should stop corrosion between the aluminium crank and the steel freewheel, so it may have actually helped as the freewheel wouldn't have been as firmly bonded to the crank in the first place - I just slap copper grease onto joints like that...

Anything super tacky from Maxxis would get my recommendation - 2 ply for the back tyre. I have minions, 2.35 front, 2.5" back and they're great ...

What's too long to a certain degree is a matter of personal preference. Post a photo of you on the bike and you might get a better answer (Even comparing it to photos of other people on their bikes might give you an idea whether it looks right). For your height the short version of a given frame sounds like it should be a better option. If the bike feels fine (No shoulder/back pain, easy to weight shift onto the front and back wheels etc.), then it may be just a matter of getting used to the new frame - If you're not seeing an improvement after a week or two of riding it then something is likely to be wrong alright...

The internals are two sliding cams with teeth on their outside that engage in a 120 tooth ratchet ring. I've got one on my XC bike - only difference is mine is silver, has Superstar written on it, was cheaper and came with a hollow steel QR skewer: http://www.superstarcomponents.com/HubProduct.html I wouldn't rate it for trials, but the guy in Superstar I emailed before buying said it's given him no trouble on his 4X bike (He said he opened it after 9 months and it was still clean inside) and I've had no trouble with it on my XC bike either (Probably 4 or 5 months, hasn't had ludicrous mileage, but has had enough to show up obvious flaws) - bearings are really smooth and it sounds like beeeees ... I'll probably get one for my DMR soon too - fed up with the 16 engagement points on the current hub - if it survives a year or two on that bike I might trust it for trials...

Thanks Adam, I'll get on to you next week and post the broken fork back to you if you're ok with the crash replacement thing. Though they would make a nice trophy for my garage, so I might keep them - can't decide... What length are the Onza forks? Is the Tuf Guy fork good? This Tuf Guy fork looks pretty suitable (I must have missed it earlier when I looked on the Tarty site) - http://www.tartybikes.co.uk/product.php?pr...;category_id=40 This would potentially match the colour scheme of my bike : http://www.supercycles.co.uk/site_details.asp?ProductID=599 The fall guy one is a monster...

The forks I have are Echo Urbans - they're supposed to be stronger than the control ones... The only thing that can be said with any certainty in forks is that they will break eventually, so I'm after the option that's less liable to slap me hard into the ground - I got away from this one with a sprained finger and some skin loss on an elbow and knee ... Out of curiosity what is the warranty period for the forks? If there's a crash replacement offer or something that won't put you out of pocket that'd be cool as I'd have it as a spare for future use. A disk only steel fork would be ideal. You wouldn't happen to have one of these around? I reckon I'll order the gusset before the end of the day unless I see a better option. I can't find Curtis or Leeson in the internet weirdly - though I am supposed to be working...

The forks were bought brand new with the rest of the bike in January. I tend to break stuff a lot through fatigue because I do small/medium sized stuff over and over again for hours to build confidence and skill slowly and I could not be called light by any stretch... Since I've been able to afford parts designed for trials use I have had way fewer failures though. Once I stopped using 1" steerer tubes some time in the late '90s (Snapped steerer tubes are hilarous provided you're not the one riding when it fails), it would still take me a couple of years to crack/bend a fork (And these were OEM Trek/Raleigh forks, nothing special). Since I got the new bike I have been experimenting with more front wheel based stuff though thanks to a grabbier front brake, so this is contributory, but I'd still expect it to last a year (That's when I was planning to replace the fork, handlebars, stem and chain anyway, I'd expect 2-3 years from the frame).

I reckon the tuning forks will be too short - my bike is already really low at the handlebars compared to anything I've used before, but dropping another cm might be too much. I'm also nervous about second hand stuff, so even with that tempting price I'll leave it. Good suggestion on the Leeson/Curtis stuff too - I'd forgotten there are still a few steel specialists still out there ... Can anyone find Curtis and Leeson products for sale or their websites though - google turns up nothing ...

Design of an easier, quicker way of mounting Magura pistons (Or a QR system for 4 bolt mounts to get the wheel off easily), especially with a booster would be an interesting one, as would a well designed, easily adjusted/self adjusting, impact tolerant chain tensioner. In terms of geometry, trials bikes are all pretty similar (For a given riding style) anyway because that geometry works well, so I wouldn't say there's a lot to innovate on there. A means of keeping tubeless tyres seated at low pressures on wide rims so they can be used for trials would be pretty cool (Though given my XC bikes runs tubeless and it's not noticeably better for grip or rolling than tubed and that I managed to pinch flat a tubeless tyre (Supposed to be impossible, but it clearly isn't), justifying the market may be difficult).

Here's my current Echo Urban - it snapped without giving any warning while I was dropping off an 8 inch ledge (Fatigue cracks were evident in both legs after it broke), so I'm not buying another aluminium fork - at least steel will tend to bend rather than just snap... Has anyone experience with the Gusset Jury SL fork? I'm looking for a steel fork with a disk mount that people find reliable and that if it does fail (Inevitable if you use it for long enough) it fails by bending rather than snapping... Here's about the best price I've seen for it: http://www.leisurelakesbikes.com/product/g...px?&id=7825 What other steel forks are out there that are between 400 and 410mm and rated for trials?