8 02 2014

Over the last wee while I have been pondering bikes. Not so unusual, but things have been a bit more focussed than typical. The Vertigo Cycles fat bike is taking shape and some decisions regarding parts were required. It is not until you sit and look at the current state of play that you realise just how many ‘standards’ there are. One of the main decisions has been dropouts (front and rear) for this bike.

As Sean recently pointed out: “so just in case anyone is curious, fat bikes are made with the following FRONT axle “standards” 9×135, 15×135, 15×142 and 10×135 rear. Do you know where you can buy an aftermarket 15 x anything skewer? Me neither. 12×142 woulda been a good idea y’all if only because it already exists.

And the rear “standard” is: 10×135 offset, 12×142 offset, 10×170, 12×177, 10×190 and 12×197.”

Then things get more complicated still. This bike will have Paragon sliders, and I would like it to run a shimano saint derailleur as a direct mount (ie, the b-link is removed, the derailleur hanger is angled back rather than down and the whole shebang is stiffer and further out of the way for wheel fitting). Then, if i have my druthers I would like a 177mm thru axle, probably DT swiss. This means the drops have wee pockets to aid wheel placement and the thru axles are just great. But wait! The Paragon sliders are available with Maxle 12mm- a 1.75mm pitch thread- Shimano 12mm- a 1.5mm pitch thread and Syntace & DT swiss- a 1mm pitch thread. Some of these are available direct mount some with traditional hanger.

My head hurts trying to work it all out.

Then again, I have a 29+ bike coming from Kris at 44 Bikes. This will replace the Krampus, which I have enjoyed very much. Why replace it after barely a year of use? Well, the trick with the Krampus is that it was made to fit 73mm bb/135mm rear hub standard kit. Very cool, but if you take away this restriction, instead using an 83mm bb and a 150mm rear hub, add in a skilled builder experienced with fitting drive chain and fat tyres past short stays, you can sneak that fat knard into a 16.5″ chainstay.

Why wouldn’t you want to do that?

Truth be told, I don’t think I am going to fully realise the potential of 29+ bikes until better tyres become available. The Knard is fine until you hit wet roots, then it is an issue. It would be really nice to have a more aggressive tyre. The word is the Dirt Wizard will be around in spring – this new Surly tyre looks much more aggressive, but is likely to be a 2.75″ so we’ll see. If I had my druthers I’d have a 2.8″ Maxxis Minion DHF.

This bike will also have sliders. And a SON front hub, maybe 135mm, maybe 100mm.

So… here we go again….it is a *good* problem to have though!



30 07 2013

There’s been a load of stuff happening but not much riding. Things should turn around soon enough, hopefully as the good weather gets reinstated. In the meantime, I have been using the sewing machine a bit more. The first project was a saddle bag. Why? aren’t saddle bags easily available? Yep. Indeed, I admit to owning several Jandd ones that are all pretty good. Define pretty good? well, they are all made of durable cordura, have good quality, strong zips that throw off mud, are a reasonable size and don’t flap around too much.

So why would I want to reinvent the wheel (so to speak)?. Well, they are not quite big enough, they are not light, (I know this is a relative thing, but lots of heavy webbing and cordura might be overkill), the openings are relatively small, meaning you often have to completely unpack to get at the contents and they are not water resistant. Probably most importantly, they are not made by me and I am becoming quite interested in bike bags. I mentioned previously my general ideas for making bags. The summary would be I want to have the option of lots of well placed, small-ish bags (so they can be made light, and due to not stowing much, are durable enough whilst being less likely to flap around), securely fastened on the bike in non-awkward places, allowing me to carry enough stuff (kit, fuel and water) for longer rides and allowing me to leave the back packs at home.

Under the saddle is a great place to stow some kit. The trick is to use the space in such a way that I am unimpeded when I need to get behind the saddle on steep stuff, but allow reasonable volume for stuff and have said stuff easily accessible.

The bag was mocked up in cardboard, I tried to think through the placement of straps to keep it solid and I used materials in such a way to minimise weight, keep shape, resist rubbing and make it light. I did forget to sew in the seat post loop of velcro when I had planned to and that forced me into some X-Pac yoga, trying to get it attached. I used 500d cordura for the top panel of the front wedge, VX07 elsewhere with strong polyamid webbing and velcro to attach it to the saddle and post. The closure is a roll top with side release buckle and a small run of plastic under grosgrain on the non-buckle side to aid rolling.

I think overall, I succeeded in concept. Of course, the proof will be in the pudding – it needs to get some use! This bag will also act as a first step in making a 3-5 ish litre under saddle bag, that will require much more thought and effort to make it stable and maintain it’s shape in such a way that it does not rub my legs. This one fits my post to saddle angle very well and is a great fit with no leg rub or interference getting off the back of the bike.

So, more as it happens.

Next was another feedbag effort, putting into practice what I learned from the first one, but improved construction, less materials, better mounting and a ‘right hand’ shape to complement the first, ‘left’, one.

In this case, I used 160d cordura for the ‘bellows’ closure, with heat sealed and folded seams, instead of grosgrain on the edges to combat fraying and the VX07 for the main bag. I used a mixture of 50mm and 25mm velcro for attachment, but will update the placement of this next time. My stitching was much improved on the oval bottom seam, but I still have a lot to learn!

I have continued to learn a lot with each step, although I am sure the rate of acquisition will slow down! I have also gained from some new bits and bobs to make my tasks easier, including this wee pair of snips Trina got me…they are ace! even for fat fingers like mine.

I built a wheel for the upcoming cross bike project. Basically, I hardly ever use my singlespeed cross bike. So, it is going to get some gears, courtesy of a messed-around-with Saint M800 rear derailleur mounted to a 10mm thru axle, with a Zee hub which I just built into a No Tubes Ironcross rim. It built nicely, as do all the No Tubes rims I have used, though they do persist in under estimating the ERD. The idea here is a 48 tooth front ring, with an 11-34 rear and a Dura Ace bar end shifter. We’ll see. If it doesn’t work out, it will also fit on to the pink IF.

Ok for now.

Monkey off my back.

14 07 2013

So sunny, still. With a full day to go and mess around in the hills, a long run of very dry weather and stable conditions, you might just try something a little out of the ordinary. I’ve been turning over a crossing of Ben Macdui as part of a route ever since I first dropped down to Loch Etchachan and made the mistake of riding past the shelter stone, before the most hideous ‘schwack ever down Strath Nethy several years ago.

Heading down Coire Etchachan to Glen Derry is the clever plan. All that remains is connecting the dots: how do you close the loop? With a relatively early start and the super stable conditions, I knew I could get up Macdui pretty quickly and travel light – no need to take thermal and winter layers. With B.A’s help, the descent would be fantastic, so the only remaining question was how to get back to base. I decided to start at Feshiebridge and take in some of the Inshriach trail, before heading around Loch Gamhna and Morlich and taking the ski hill road. The two options for returning without making the loop massive are Glen Feshie, in which I have recently been bitten and remain a bit shy, or the Lairig an Laoigh. This pass is rocky and usually wet and boggy – not a problem on this day. If you have to use it, I much prefer north to south, but on this occasion I was just going to have to suck it up.

I made quick time up to Macdui and decided, due to having been there once or twice before, that I didn’t need to go to the actual top. Instead, I tracked around the vague trail to the ruin that marks the start of the trail down to Loch Etchachan. No snow today, just a rocky, steppy, highly enjoyable technical descent. I don’t usually ride on the limit when I am solo in the backcountry, the risks if you hurt yourself properly are not worth it and I don’t want to have to rely on any emergency services just for the sake of an extra ‘cc’ of adrenalin. However, I was pretty close to my ragged edge on this drop, slamming the ground at one point and lightening my Saint cranks a smidge.

As I came to the throat of the Coire and looked down on Glen Derry, I couldn’t help but smile, soaking in the view – what an environment! The higher you get, the higher you get for sure! the views of the peaks around were intoxicating. Truly, when the weather allows you to feel comfortable enough to take your time and look around at that altitude, you are blessed!

I tore myself away and danced past a party of young walkers before making the scrabbly, loose descent down to the Hutchison Hut, which was in fantastic condition after recent renovation.

From here the Lairig an Laoigh beckoned me on. The climb was rough, water damage to the trail obvious and I was walking more than I was riding. I knew that this would continue until the Fords of Avon, where I met 2 hikers and their ample supply of vino tinto. Why not, eh? it was shaping up to be a beautiful evening and there had been no midge and the only cleg I saw all day landed, somewhat optimistically, at my feet before a size 43 ended his reverie.

There is somethign to be said for pedal removal if you have to make a prolonged ‘schwack. Every time the bike gets hung up on vegetation or a rock, the rear of the bike swings around and the pedal took another slice of the back of my leg. Those Alaskan backcountry bikers know their onions! On this occasion I decided to just put up with it, afterall, the pass is short, right?

Not short enough! but after passing the tors of Bynack Mor, with a short yomp up onto the improved access trail, there was only 400 sharp water bars and the descent past the Ryvoan Bothy until I could take the soothing, smooth tarmac back to the car.

The route took 7 hours total. B.A behaved impeccably and I felt like a large monkey had been plucked from my back. I don’t think Macdui would be good as part of a bikepacking route: the trail deserves your full attention and effort on the way down and I think even if you were travelling extremely light, as I was almost exactly a year ago, it would encumber you to the detriment of enjoyment.

Ok. Next up, some buff, woodsy singletrack, no rocks. Or some sewing…

New fangled.

30 06 2013

After the XT hub imploded on the Krampus, I decided to change the drive chain on the bike at the same time as re-building the rear wheel. I had one of the new-fangled thick/thin chainrings from Works Components, which I had pre-ordered out of curiosity rather than need. The ring is nice though, with reassuring thickness, well profiled teeth and neat relief. It is made from 7075T6 aluminium, which has seemed durable in the conditions I encounter. I was also curious about how an 11-36 cluster would feel. For the last couple of years, I have been happy with the range a 34 tooth ring with an 11-34 cassette gives me. On Maul, I even have a 35 tooth ring as that bike is aimed at going quickly. The engine sometimes lacks horsepower though, so it may be reduced to a 34 soon!

If you look closely, the tooth counts on a 11-34 cassette are 11, 13, 15, 17, 19, 21, 23, 26, 30, 34. An 11-36 is a little different in the lowest four gears. The gears I probably use the most, those in the middle, are the same, so I felt that I may well gain from the increased range when things get really steep. Having spent so many years on singlespeeds, I am undaunted by grunting up climbs or walking if needs be, but particularly when loaded with bikepacking kit, The Krampus takes a wee bit more effort as you ascend than my other bikes.

So, the tooth counts of the 11-36 are 11, 13, 15, 17, 19, 21, 24, 28, 32, 36. In going to 10 speeds, I needed to replace the rear derailleur and shifter as well. I have also been curious about the thick/thin ring’s ability to retain the chain, along with a clutch style mech. So I decided to fit a Zee rear derailleur. This is not only a lot less expensive than a Saint rear derailleur, it is designed to cover the 11-36 cassette – a whopping 25 tooth range. Most short cage derailleurs will only work with a reduced range, as the length of the jockey wheel cage is too short to take up the slack in the chain required for wide range cassettes. I am unclear if the B tension range is different, or if the geometry of the upper jockey wheel placement is different as well. The Saint, depending on where you look, seems to work with 11-36, but Shimano officially rate it to a maximum of 34 teeth. I don’t want to find out that it causes undue stress or damage on the derailleur in the middle of no-where so the Zee seemed to be a good option, though I fear I will miss the Saint’s added robustness and bash ‘rail’ that runs next to the parallelogram to protect it. In parts, the Zee uses stamped, formed metal sheet rather than (presumably) forged aluminium pieces as well. It will be interesting to see how the function is affected by this over time, or whether it is purely for weight and aesthetic appearance.

The rear wheel build was, well, awkward. Maybe because the rim is singlewalled and it had already been built? there was also a small flat spot on the rim, not noticeable to the naked eye, but the Centrimaster showed about a 0.3mm sharp, dip that could not be trued out – a clear sign of a dent in the rim. I don’t really know why, but the tension range in the wheel is broader than I would normally like – around 15% difference – but otherwise the near symmetrical spoke angle and tension led to a wheel build I am relatively confident will be durable. Of note, the ERD at 617mm and use of 298mm disc side, 300mm drive side led to perfectly full nipples and only some very minor Dremeling in order to remove protruding spoke. Again, I used freespoke for the calculations.

The drive chain parts went on very easily indeed and removing the Paul chain keeper felt speculative to say the least. However, on a quick ride around the block, bumping into curbs, jumping and hopping, the system was quiet and there was no indication I might lose the chain.

I will be interested to see how this system copes with Scottish conditions and probably more pertinently, wear of the ring. The chain line is pretty good on the Krampus, so I don’t think there will be undue wear on the wide teeth on the ring, but over time, the chain will no doubt become more rattly on the ring and I am curious to know whether it will have a reasonable service life or not. Obviously, as SRAM may take legal action, at least in the USA, the after market thick/thin ring market may well change soon as well…


22 06 2013

A few days ago, I decided to explore an area close to home. In order to make a day of it, I planned to ride out through Mugdock, poke around the triangle of uncharted territory in question and then follow the West Highland Way further until I could join a trail that used to be an old railway line. This leads to Croftamie, a small village west of Glasgow, where I could ride alongside a meandering burn I have always been curious about.

It was a beautiful day, with a brisk wind that kept the midge at bay, which was most welcome when I took the narrow trail through dense foliage between Strathblane and Glengoyne distillery. The trail is also on an old rail line and has a very steady grade, but it has grown in, no doubt due to the heavily used WHW being routed close by.

All in all, it was an interesting diversion. For a while, I followed the WHW, then turned, took a narrow bridge across a river and climbed up towards Croftamie. Another, higher, bridge offered fine views of the mountains and some gorgeous clouds. There was no rush, so I stopped to have a sandwich and watch as the little fluffy clouds rolled by.

The trail from Croftamie was short, but sweet. It popped out at Dalnair House, an old baronial mansion that later became a nursing home and has now fallen out of use. It is a beautiful building and as I watched a deer bound past a dilapidated tennis court I wondered what would become of it.

From here, I took the road up to Queens View and the Whangie, then back into Mugdock and home.

It is interesting to look more closely at what is under your nose. You may not always discover a gem, but it is always enlightening.

During the ride, the rear hub on the Krampus became considerably noisier than I have been used to. It slipped several times, which it has done on occasion since new, but this was worse. A few nights later, as I pedaled out on a group ride, it gave a loud crunch on a rocky climb and from this point on it refused to freewheel consistently. I needed to bail on the ride and by the time I got home I had to pedal continuously in order to avoid jamming the chain because the cogs would not allow me to coast. When I first got it, I was unsure what I would think about the Krampus, so I didn’t want to sink too much money on componentry. However, I recall feeling uneasy about using the M785 XT hub. I had heard rumours of problems with other recent XT hubs, but assumed it had been ironed out.

On inspection, the freehub body mechanism was toast, I was in no doubt that the pawls had shattered. With replacement of the freehub body being around the same cost as a new hub, and with no indication that Shimano has changed the design to remedy the part. I decided to invest in a better quality hub. A Hope Pro II evo will be built into the Rabbit Hole soon. Again, spoke length is causing me a bit of a headache, ideally the non-drive side would have 299mm spokes. I will perhaps go into this in more detail soon.

The situation is, of course, disappointing. The wheel has been in use for 3 months and I would not expect to have to rebuild a wheel within 2 years usually. It is a waste of money in terms of replacing spokes as well. XT level componentry is usually bomber and it looks like Shimano dropped the ball on this one, which is (fortunately) rare.

Along with rebuilding the rear Krampus wheel, I will be building a geared rear wheel for my ‘cross bike. The Iron Maiden lies unused for much of the year, a situation I want to change. It is a singlespeed specific frame, but I intend to use a 10mm thru axle rear hub (built on to a No Tubes Iron Cross rim) with an old Saint M800 rear derailleur, a Dura Ace bar end shifter, a 9 speed cluster (11-34) and a 48 tooth front ring. This will give me a broad enough range to tackle steep-ish climbs off road, but allow a good turn of pace on the tarmac. Hopefully, along with file tread 35mm tyres, this will make for a versatile set up.

More as it happens.

The Xtracycle has been in almost constant use. There is no doubt as to it’s versatility – dropping off Daisy and hauling stuff – but it can feel a little heavy up hill. No matter! you will grow strong, pedaling this sort of bike!

Lastly, I used Continental Revo sealant and a 2.2 Mountain King II Protection to go tubless on the back of Maul. It has been several years since I used a tubeless set up. Once I get some miles in, I will decide whether it will stay or not.