psycholist

How can you identify a trials rider's coffee cup? It's the one with the ground rim.

If you want to go west instead (At the definite risk of having to ride in bad weather ), Ireland has a few nice spots... Best thing about it is the cops have no idea what trials is, so they pretty much leave us alone for street riding - there's good stuff in Dublin, done Laoghaire, Limerick, Cork and Galway... I've ridden what I could of the park in Sabadell and it's brilliant too... If you're running Maguras you'll need to wipe the dust off the rims every so often to keep the brakes sharp it's that dry ...

For general bike stuff I use these sites regularly (And have had no trouble dealing with them and been really impressed with the warranty support from Superstar): www.chainreactioncycles.com www.superstarcomponents.com - also a handy place to get titanium bolts... Between those two and Tarty all my XC and trials needs are met...

When my GU shows up hopefully very soon I'll be able to comment on how that feels - It should be very similar to the Echo Control I already have (which is brilliant) as I chose the 35mm BB rise. I bought the GU so I can run a rear disk on it - very few other stock frames have this option and last night in the snow my back Magura was slipping quite a lot as the rim got icy while the front disk never skipped a beat. Though I will admit I spent a lot of the night drifting icy bends with the back wheel locked and practicing skidding backwards down hills with the front wheel locked, so not exactly trials use, but if the back brake was working as well as the front proper trials riding would have been some sort of option ...

That fantastic work - It's inspiring to see some proper artisan bike building and this is a cut above anything I've seen recently . Couldn't justify the cost of anything other than the stuff the far east churns out the way I treat bikes though - time spent polishing is time that could better be spent riding ... If there's anything in a long travel XC hardtail with a nitrided finish I'd consider it though ...

You can be damned sure the bearings you've replaced from a hub will be complete shite in terms of the material quality compared to the OEM King ones. It's the reason the bearings in my 6 year old XTR hub still have a near mirror finish and run perfectly smooth while a Deore hub will feel like shit after 2 or 3 months of the same use.

The section labelled 'Still not convinced this is possible to machine will be the first place the frame cracks in use. Reentrant corners, especially when they're located directly on a load path will produce crazy high stresses. I'd merge the chainstays flush with the end of the BB shell.

2 options - fit a bigger disk so the caliper is further away or lace the disk side of the hub with all the spoke heads to the outside of the flange. This is nasty looking and the spokes will be tight where they cross near the hub, but it can be done. Otherwise fit a different rim.

If you're planning on testing the frame and fork after you build it, here's the relevant European standard - If it can't survive this it'll be dangerous to use as a trials bike anyway: http://www.bike-eu.com/public/file/archive...glish-draft.pdf

I'm not sure what CAD program you're using - looks like Solidworks - you should be able to put in offset while keeping the forks straight bladed by selecting an axis where you want the legs to join at the bottom of the steerer tube, selecting a plane at the same time and then selecting the 'make new plane' option. Then draw your sweep path along that plane. Works that way in ProE anyway. Straight blade forks are the way to go since putting the same curve on both fork legs will be a manufacturing difficulty depending on the equipment you have handy, and welding the brake mounts to a curved fork blade will be a pain. I'd put the brake mounts on the front of the fork every time. The reason being that by default the back of the fork legs will be in tension at all times except while you're endoing, so the fork will fail more quickly all other things being equal with the mounts on the back. The last fork I used with rear brake mounts was an Echo Urban, lasted all of 6 months before snapping. The replacement Onza fork is still fine 1.5 years on, though it is steel ...

I'd say there's no way I'll be able to get people mobilised for a road trip that early ... Couldn't get any other takers on the Sheffield trip for the Moto Trials round on the 10th either...

Sounds like a flan - I'll wait till next year and see how cheap ferry tickets are once the misery that is January sets in ...

Hopefully there are a few lines mere mortals can attempt too ... Is this the same place or are there now two indoor trials venues: http://www.trials-forum.co.uk/forum/index....howtopic=145456

You'll need lots more fillet at the sides where the chainstays curve inwards towards the BB shell and at the bottom of the BB shell. Cracks will grow very quickly off those areas as their high tensile stress and already quite acute angles. The brake mounts really don't look very strong at all. Fitting and adjusting the brakes to them will be a real pain since there's no way to loosen the brake mounts off properly without straining the frame. The V shaped slots in the chainstays look like a significant fatigue cracking risk too. If you're to get away with a setup like this try using C-Section bars for the top and bottom of the brake mounts to increase their bending stiffness so the chance of buckling or bending from braking force is reduced and use a rounded or flat cut on the seatstay where the brake mounts are fitted rather than the V cut.

How far from the ferry to Holyhead? It looks like it's within striking distance of Ireland if we were to make a long weekend of it... Any photos?

It's coming together very nicely. The brake mounts look very weak though. I reckon unless there's a lot more reinforcement that's not obvious in place when the brake clamps are fitted, the mounts will probably buckle on heavy landings. Putting the brake pistons through the tube is a nice design detail, but it adds a lot of stress risers to the frame. The seatstays will stay mostly in compression, so they're less prone to fatigue than chainstays (Fatigue needs a tensile stress), but with all the cross section changes there will be local tensile stress all over the place now. Definitely smooth out all the corners too - the edge where the BB shell and the chainstays join definitely needs a big fillet. Internal corners will be a lot harder to smooth after manufacture, so they're the priority, external corners can be dealt with by manually rounding the edges afterwards if there are manufacturing issues that make putting them in initially difficult.

I've had no trouble with the Hope I fitted in my hardtail earlier this year (Way too early to tell anyway), but every FSA headset, 3 or 4 pigs, a couple of Orbits with needle rollers over the past 10 years have all lost the ability to stay rattle free after 2 yearsish. I couldn't afford better at the time, but throwing 25 odd quid at a headset every 2 years tends to add up when a really good headset will just keep working almost indefinitely. Best headset I ever used was a Shimano 105 threaded 1" one... Even when the bottom bearing cone cracked after years of abuse (And two frames broken) it still ran smooth. If only Shimano made threadless headsets ...

It might be worth trying these http://www.soundfeelings.com/heatbands.htm Usually the tip of my rear brake finger goes numb while the rest of my hand is pretty OK, so I've stayed with normal gloves so far - mostly when it's too cold for me to go riding there's ice/frost on everything anyway...

Must have been whatever headset Echo made 2 years ago then...

Every FSA headset I've owned has worked well for a couple of years and then something goes wrong with it and the headset develops play in the bearings regardless of how much you tighten it. I've got an Echo SL in the current bike, 2 years old and it's still spot on, no grinding/play except for creaking when I load up the front of the bike, even when its freshly greased (Which I'll admit doesn't happen often).

Hold them side by side - if the new rim looks to be the same diameter the existing spokes will almost certainly fit. A handy technique for transferring the spokes is to slacken the spokes in the current build, line up the valve holes in the rims, tape them together and swap each spoke to its corresponding hole in the new rim.

I didn't think anyone could possibly have enough time to watch every trials video they can find even if you just go on youtube and watched the related videos and videos related to them etc. for the first trials video that comes up you'll be there for hours... Go riding ...

Watching this makes me want to exercise ... http://www.bodyrock.tv/

If you use copper grease on the back of the brake pads that's ok (And may help the brake work better or stop it squealing). Any other grease will get too hot as you use the brake, run out from behind the pad and contaminate the disk.

The change in bending moment isn't enough to suddenly cause a failure though. However Ali's earlier comment does suggest a very likely way in which the failure could have occurred that does implicate the spacers as the cause of failure. If the failure was down to fatigue (Which is the means by which pretty much all bike parts that don't fail in the first 5 minutes of use will fail), there is a very significant difference in the peak stress in a system where the peak bending moment being applied to the crank lines up with the end point of the crank bolt threads (Which have their own stress raising effect) compared to where the end of the crank does not line up with this point, so there are two separate lower stress peaks along the axle. A couple of photos would confirm this - if the break has a discoloured smooth area (Especially if there are what looks a bit like the growth rings in trees radiating from a point on the outside of the axle (Usual most likely start point as stress is maximum on the outside of a part seeing bending in the absence of other stress risers) as well as a rough looking area for the rest of the break, possibly with some shiny facets, then you have classic fatigue failure for a tough material (Rough dull breaks are ductile failure and usually seen in aluminium/soft metals, BB axles will often have a mix of ductile and brittle fracture surface thanks to the hardness and toughness required for that application, leaving some shiny brittle fracture surfaces). If the crack lines up with the bottom of the crank bolt threads or the point where the crank bolt ended in these threads when the crank was fitted and these points ordinarily would not have been aligned without the spacer, then there's a very good case to say that was the reason. 3mm of increased leverage isn't enough on its own though - unless the person using it snaps BB's relatively regularly anyway in which case it might take a month or two off the BB's life with failure being inevitable anyway.