Heatsink

A PU TDI - no PVC in sight ;)

Definately grind your rim, and ideally a combination of a rim that holds a grind well and some softer pads will ensure your won't need to grind again for a very long time. Then you can have the benefits of brake lock when you need it without any variability like you get with tar (wearing off) or smooth rims (moisture). Steve

Nice one :) Here's the final table then: Steve

I've added the Titanium alloy mentioned by Adam and a higher spec Steel to the comparison table - Things are looking good for the titanium now ^_^ Titanium Alloy has an equal stiffness/weight ratio to the 6061-T6 Alu 56% higher UTS/weight ratio than the Reynolds 853 I found a Ti alloy with a higher yield strength again that the one mentioned in the web article, so this looks even more impressive in the table. The % elongation to break has dropped to a similar figure to the Alu, so maybe it will perform just as well but not better than the alu if bent back. For completeness all that remains is a higher spec Alu such as typically used for bike frames. Steve

EDIT: Nice one for the higher end figures for the Titanium there ^_^ Any figures on stiffness too?

Here's some quality information for you :) I couldn't resist putting some proper figures on things to help see things clearly. Have a look at this comparison of typical material properties. I just had a search through www.matweb.com It should be noted that some steels used in bike frames such as the Reynolds and T45 stuff are upto 1/3 stronger than the 4130 listed. I've heard quoted that Titanium is typically 1/2 the stiffness of steel, although this wasn't what I found from the information I picked out, the Ti was 83% of the 4130 stiffness. Looking at the Strength to Weight ratio for this Titanium, it's 30% of that for the Alu and 59% of that for the Steel. Stiffness to Weight it's equal to that of Aluminium which is 44% more than that of the Steel quoted. I'd say that these two propeties above are the key things when thinking about Trials frame design (whilst keeping an eye on Fatigue too) So if you took an Aluminium frame such as an Onza T-rex and you wanted to make a version from Titanium in the same weight, you could use the same tube outer diameters with thinned walls (Titanium being 1.67x the density of Alu). The resulting frame would be equally stiff, less dent resistant and crucially, only 30% of the strength ^_^ Alternatively if you wanted it to be equally strong as the Alu version all over, by thickening the tubing walls, then the final weight would be 70% more to achieve this! The remark about being able to bend Titanium back loads of times before it breaks - You can see in the % elongation to break that it's possible to stretch a piece of this Titanium +54% before it breaks which is better than that for Alu and Steel, although I'd say this is a less important factor than being able to build a frame which has decent strength and stiffness. One final thing that seperates Aluminium from Steel and Titanium is the Fatigue Life. Steel and Ti have an Endurance limit whilst Alu doesn't. If you don't know what this means, have a look below: Fatigue & Endurance Limit Info (See page 5 and others) In summary Someone may be able to find some more representative figures for higher spec Titanium, but from my quick look the combination of material properties I can't see anything to endorse the huge price tags usually associated with Titanium frames & parts contary to what MBUK (who are trying to sell bikes for their advertisers) would have you believe. I'd like to be proved wrong though! Steve

I bought some Etnies for riding in, but the soles are noticeably more slippery than all my other shoes >_< They are durable though, but I'm currently riding in a pair of Next shoes I bought in a sale intended as shoes for work. The soles on them are much softer and so the grip is top notch. Plus they're slimline and lighter compared to my Etines. I'm at the age where I don't have to worry about wearing the wrong llooking shoes out riding, which is fortunate! Steve

I'm pleased to introduce the very latest Vid from Dan Burton. Some huge 20" riding going on from the Danster! Dan's been busy thrashing my pads and helping me nail the geometry for my imminent CNCed 4 bolt booster. Whilst doing this he's managed to gather the following riding footage showing how big he's going. He makes it look so easy! Link to the Vid download: www.heatsinkbikes.com - Please don't lazy link! Some of the footage is quite raw, and the vid recording quality will be much better in the next one which Dan is already pencilling out. Enjoy. Steve

Anyone know any sites for unlocking the P800 from Sony Ericsson?

I'm disappointed that you can't spell disappointed, and not professional enough to spell professional correctly :ermm:

"Maher" sounds like "Meilleur" (May Er) in French which means "best". May or may not be related to this though. "Merde" (Mairrrr D) is s*** in French, and here's a random fact: In French the word for prostitute is used to curse, and "Putain" (Pu Tan" is a stronger swear word than "Merde" which has only has a similar strength to "Crap" in English. Steve

Is it powercoated?

I have a recommendation for an upper body work out which involves time spent carrying an increasingly heavy todder in one arm, whilst I get breakfast/do the washing up/tidying away stuff! He's walking all over the shop now and is trying to eat everything he finds so I have to keep my eye, or rather an eye on him sometimes! Another work out routine is running around on all fours, roaring like a Gruffalo (it makes him laugh as do all "Scary creatures" that roar like Tigers and Dinosaurs!) to help with suppleness. EDIT: Check out that song vid on the Gruffalo site! That's me in a weeks time that is.... Steve

On the casting, The RB lever has indeed been cast and machined after in places. It would indeed be very costly to machine it completely from billet to produce the rather impressive form with so much material removed. The RB weighs 21g compared to the 05 lever at 27g, plus the RB looks much better! I've noticed that those Bonz levers would be the cheapest to have machined, but aren't as cool looking or optimised for weight/stiffness and ergonomics as the RB and Fresh lever. If a jobs worth doing.... It's one of those things that if the volumes are large enough then the casting route would become cheap enough as the cost of the tools etc was spread across the quantity of levers made. But you need to stump up many thousands of pounds (in the UK anyway) to get the tools made and running. I'll keep tweaking the CAD for the levers and we'll see if, like it sounds like Aaron is trying, I can find a decent price without having to compromise on the design of the lever. As you would imagine, the more expensive lever of the two CAD ones is the better looking version! The one with the slots running in the the same direction that you pull the lever. Steve

This photo shows how: I can't see a spring there, and interesting to see no channel on the roller. Simple is indeed good (Y) You can see that it mounts onto 2 Leeson specific mounts on their frames and one bolt is used to hold the roller in the desired position either above or below the chain. Steve

The steel snail cams (hard wearing and stronger than Alu) like Fresh do have to be superior to Alu versions (Y)

I was wondering if I could get a more comfy lever for my 2005 Maggie. The RB shape is much loved because of the nice one finger pocket it has, and also they've done a great job slimming down the weight whilst making it look cool too. I really like the look of the RBesque Fresh Lever for Pre-2005 maggies - Nice job Aaron! I've been experimenting with a few machining schemes for the 2005 Maggie, but it's pricy! I admit that the lever shape shown below at the moment is too much like a banana because is was a quick CAD model to get an idea. If there's interest and I have more time, then this could see the light of day (Y)

I had a design completed based on an easier to fit Rohloff type tensioner. The problem was that it cost more than 2x to make compare to the RRP that I had in mind! Also there are some spring retention problems if the two sprockets can be adjusted. Here's a sneak peek of some CAD - the off the shelf parts are missing since this was for a machining quote: If springless designs are the way to go, then this is good news for bringing the price down to around the cost of a mech, which is what I had in mind originally. But I'm not sure if I want to make another tensioner that works on the Rennen concept when Aaron has already put so much work into his, so I have no immediate plans especially since I already have my hands full working on new booster variations, pad testing and moulding plus Alu Magura backings. Thanks for your interest though! Steve

I've been running a Rohloff. It works well but stupidly expensive and is fiddly to fit. Out of curiousity I've just put on one of the springless DMR ones which looks like below (but with a different logo on it & with less chain length and slack) It works on the same principle as the Rennen, which the Fresh tensioner is based on: This method is well received in the Trials community, with increasing numbers of UK riders running the Fresh one and I read that the Rennen is a firm favourite over in the US where it's easier to get hold of. I haven't had time to ride the DMR yet, but it certainly looks smart tucked away, and was very simple to fit. It was cool to be able to remove a couple of extra links from my chain and now it looks very short and efficient. From feedback I've read on TF I think that it may be some of the finer details with which have caused frustration with the DMR version, because the principle seems to be sound. These are namely that the lower bolt snaps easily (it's made in Alu so is no doubt meant to break rather than transfer the knock to the frame) and I've also heard (rumour and hearsay!) that the roller wears quickly. Another point is that for some reason DMR have used a seperate part to join the axle to the tensioner (see the third bolt which is attached to a black Alu part that fits onto the axle), which seems an example of over complicating things. The sprung DMR tensioner I also have gathering dust is overcomplicated with loads more parts than needed, and it also requires a large number of different sized Allen keys including all the small ones that are lost somewhere down the back of the sofa. Maybe this 2 part design is less robust than the Rennen/Fresh one-piece design for those side hopping accidents. I'll soon find out it if can take the knocks because my sidehops are pretty rubbish! I was thinking that the bolt and roller can be sorted out by fitting other parts, which admittedly does involve some hassle and cost, but basically may allow the DMR to be used reliably. For example instead of the Alu bolt I've used the Rohloff's steel one, and I've paid close attention to not over tension the chain which may accelerate the roller wear. It will certainly be very simple to get some replacement rollers made up and try a variety of materials should the durability be an issue. I'm going to see how it performs over time. Steve

Jon's the man for acts of kindness (Y) Let me help myself to his LHM oil, gave me some brake cables and also carted my parcel shelf and coat half way across the country when I left them at his house! Steve

There are indeed too many to list! I'll single out Jon too for a special mention, since his niceness is top notch, which I found out during the SM weekend where he hosted us all in his house. The crazy Metro driving still haunts me today though! If I was to start listing then it would include virtually all the SMs and the majority of people I've chatted to on this Forum :D Steve

This is what I've been trying to improve from the starting point of Janson's design - improving the leverage where possible. The brake boss has been moved up as high as it can and the form modified to allow even closer placement to the lower mount bolt. There is alot of variation of 4 mount position across frames I've found, and for some this same brake arm would have the pad in the half of the slot closer to the pivot. Also the slots positions vary too across different arms. Mounting directly onto the lower mounting hole may mean that the brake pad can't be fitted because it needs to be even closer to the pivot than the slot allows. An ideal position to suit the range of frames may be half on the lower mount and half below, which cause difficulties for assembly. I think the current position as used by the Bonz adapters too, is the best to cater for all set-ups. Steve

I used to have this problem with an XC bike and after a long time trying to locate the source it turned out that it was the cheap pedal bearings. The lube had washed away. It was hard to locate the source playing around in the shed because it only happened when I loaded up the pedals, i.e. was sprinting on the bike, and I didn't have a spare set of pedals to swap over so I could test. Try a 3rd set of pedals which you're 100% sure have decently lubed bearings I'd suggest. Pedals that don't click on someone elses bike. If that's not the issue then you'll have to repeat the "change one thing" at a time thing until the sound goes. Steve

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There is a rather important improvement that the o-ring based "clip" shown above in that CNCed backing has over the Coust's use of an o-ring for their backings. The Coust o-ring is only held in by glue to stop you pulling it out of the pad rear, whilst the CNCed backing shown has a solid stop of Alu for peace of mind :$ I bought some Coust pads to have a look at, and this is what I found after placing the brand new pads onto the cylinder and taking it off again a minute later :lol: Is this the problem you had with the Coust backings Lee? Steve