Equipoise.

7 12 2016

Fast and furious. The development of new* tyre sizes that is, not so much the covering of ground!

It probably goes without saying that I have enjoyed several years of messing with 29+, 27.5+ (or B+), 26 fat, 26 fatter, 27.5 fat (B fat) and even 27.5 (B) fatter. There have even been some options appearing with the 27.5 fat, not that my love for the Bontrager Hodag is in any way diminished.

I have also spent some time messing with mixed wheel sizes. Typically a bigger rim diameter on the front than the rear or a bigger tyre volume on the front than the rear.

Is it time for any conclusions?

Perhaps.

27.5×4.5 (the Bontrager Barbegazi – and recently released Gnarwhal) is the undisputed best in super soft conditions. The huge diameter and massive paw print is quite frankly remarkable. However, it is a HUGE wheel – over 770mm in diameter. This is bigger than 29+.

26 fat does an admirable job of not being too big, hefty or cumbersome but offering good floatation.

B fat (as I have become accustomed to calling the Hodag and the new Maxxis Minion DHF 27.5×3.8) makes an outstanding front tyre in combination with a 2.8 or full 3″ rear 27.5 tyre. These tyres both have insane traction, in crappy or dry conditions, but don’t add too much rolling resistance when paired with a faster rolling b+ rear tyre.

B fat as a rear tyre is tricky: both options are very knobbly tyres and as such, rolling resistance is relatively high. If this is not an issue, or indeed a bonus, fire away, with the same up front or even a Barbegazi.

29+ is the king of roll. The effect is more pronounced on the front than the rear, but there is no doubting a bigger diameter, relatively fast tread will cover (moderately rough) ground like nothing else. Special mention here must go to the Bontrager Chupacabra for being both light and seemingly durable. Not the most aggressive, but adequate.

29+ front 27.5+ rear appears (to me at least) to keep a lot of the benefits of the roll over of a f+r 29+ but – for an indefinable and physics-defying reason – feels a little more playful. about the only factor that can really make much of a difference given that some of my bikes will have the same stay length regardless of which diameter is in use, is the radius and therefore how the bike behaves over different amplitudes of hits. The bigger radius might also potentially change lean angle in cornering.

The more I read about this, the more confused I become. For starters, within the parameters of a bike, the weight of the rider far exceeds the bike and thus acceleration differences are likely to be negligible. Wheel stiffness and response are probably very, very small effects also.

The difference in gyroscopic force and moment of inertia between the sizes would seem to be too small to be detectable at the speeds we ride at (with the wheel weights we use) and the same would go for the difference in effect of acceleration with the torque that can be applied (see here for a nice, plain explanation of applying torque to a wheel and then consider the force a human can produce and the difference in wheel diameter/weight).

I have also always wondered if the gyroscopic force of a wheel *not* in line with the direction of travel affects how a bike feels (consider sitting in a rotating chair and holding a spinning wheel then twist this and you will spin around on the chair. Surely, when we tweak that move in mid air, the two wheels rotating affects your position in the air? and would a bigger wheel exert more force noticeably?

And what of B fat front? Can the added weight and girth be detrimental? particularly with the Hodag – which weighs little more than a robust 29er tyre – I believe not. The combo of low psi and ~745mm diameter (the same as a good size 29er) mean you get the low pressure smearing grip, the lack of knocks from impact and good roll over obstacles, too.

It makes normal 29ers feel like a ‘cross bike.

No doubt as more sizes become available, (I’m looking at you, 27.5×2.6) and more tread patterns are brought to market, I will refine my thoughts.

At present, B fat front/B+ rear or 29+ front/B+ rear is the best performing wheel combo for my riding.

*it all stems from the Gazzaloddi, right?





Westworld.

8 11 2016

A little while ago now, it became clear things were afoot on the West Highland Way, with trail construction beginning near the edge of Loch Lomond, north of Rowardennan.

Three years later and it would appear the work is complete.

I used to ride the West Highland Way fairly often: it was Scotland’s first ‘made’ long distance walking route, stretching 96 miles from Milngavie to Fort William, passing some stunning West Coast scenery on the way. Around 80,000 walkers use the route yearly, concentrated in the summer months and for this reason, biking on the route is best out of season.

So I found myself trundling up from Balmaha the other day in glorious sunshine – although there was a serious nip to the northerly head wind – and on climbing past the Lodge at Rowardennan, found the left turn onto the new section.

Immediately, it became clear the plan was to emulate the singletrack, which is so festooned with natural features, that makes the section from Rowchoish north to Inversnaid sublime.

In saying that, they turned the dial up to 11.

Rock steps, rock step gaps over plunging water run offs, narrow and super steep wooden staircases, fallen tree up-overs, narrow gaps through sharp rocks and edge-of-the-loch trail all combined to leave me wondering if I enjoyed it or not.

I returned by the high route, giving me time to reflect. Yes, I enjoyed it but it is a serious undertaking, requiring skill, balance and confidence to tackle on a bike. To combine it into the whole route – particularly loaded – would need a serious amount of beard stroking.

~~~~~~~~

The section i rode was 3.5 hrs. Do click for bigger pics and there are a few more on my flickr. I didn’t catch most of the techy sections as it was hard enough to do once, let alone scope for a pic…





Fixed off road.

21 10 2016

Something that came up on facepalm reminded me of when I used to ride fixed gear, off road. It is fun. Teaches you all sorts about momentum and pedal/wheel placement.

I made this video a few years ago. Interesting to watch it again…





4 years ago.

8 10 2016

Four years ago, I hatched a plan to bike pack a slightly ambitious route. Up Ben Macdui, bivi, then descend to Loch Etchachan (a trail that often generates wistful looks and knowing nods between the cognoscenti), then on down to Glen Derry to meet the crew who were intent on Beinn a’Bhuird then Ben Avon and after, I would return by dropping down to the river Avon and follow this to Tomintoul, cross to Dorback Lodge and the Braes of Abernethy to Aviemore.

It didn’t happen and I had quite a gnarly experience up Macdui. The Big Grey Man was calling my name.

I returned with this route in my mind numerous times over the subsequent years, but it wasn’t until last weekend that I finally managed to get it done – more or less.

Why less? well, I did not ascend Beinn a’Bhuird or Avon, instead I headed to the south side of the River Dee and ascended from Crathie, on the road, until Corgarff Castle where I took estate tracks to rejoin the River Avon at Inchrory Lodge, before heading north to Tomintoul and completing the route aforementioned.

I had been weather-watching intently because I had a 3 day window and needed 2 days to do the route. As the wet weather of recent weeks subsided, I knew that some of the boggier ground on my original route (including the classic section to Loch Builg) would probably be a bit miserable, but having ridden various alternatives in the past, it was easy to re-route and I felt that I had minimised any needless misery, but kept all the fun stuff in.

I overnighted near Loch Morlich with a view to an early start. The sun was shining and the azure of the sky brought a broad smile to my face when I finally made it out of my kipsack. Gear was stowed and checked a final time and I rode out the logger’s trail to Glenmore Lodge then up to the ski hill and on up Coire Cas.

Having fitted an 11-46 cassette recently, I was able to pedal the lion’s share of the climb and once up top the views opened out and I took a deep breath and drank the majesty of the Cairngorm in.

It really is an otherworldly environment and I always feel I have transcended my everyday life as soon as I am up there. I had hoped to ride the bulk of the descent from Cairn Gorm but some of the bigger rock steps foiled me as my Revelate seat pack forced my body weight to stay high and forward.

Scott at Porcelain Rocket is working on a dropper friendly bikepacking set up and I’ll be very interested to see how this progresses. Most often, one tends to avoid the more technical routes on a bikepacking mission, but there are occasions where it could prove indispensable.

Back to the trails….

I carried and rode over Stob Coire an t’Sneachda, enjoying the rocky, steppy trail, then dropped to the saddle before Cairn Lochan, filled the water bottle with the icy cold, clear water from the Allt Coire Domhain and continued south west to join the trail to Macdui.

A beautiful, clear view over to Braeriach and Cairn Toul was reward for the hard work and after a relatively brief carry over the rocky section, I took to the summit cone of Macdui, where I met Jamie Pierce, whose pictures of riding in various locations around Scotland are a great inspiration. A good chat, then up to the top and after a few pictures, I dropped to Loch Etchachan.

Please click to see original and see the trail, snaking into the distance...

Please click to see original and see the trail, snaking into the distance…

The technical track is fantastic. I had some concern over how it would ride loaded, but Snow Job took it all in stride. I filled the water bottle again at the brook that feeds Loch Etchachan and took on the trail beside the Coire Etchachan Burn, down to the Hutchison Hut. At one point, I nearly ass-over-tea-kettle’d into the burn as, again, my C.O.G was thrown by the saddle bag and I high-sided after a step down and careered off to the left. Serendipity was the only thing that saved me from a painful crash down the steep side of the banks of the burn.

The ride down Glen Derry, as the day began to grow old, was relaxing. The first hard section of the loop was done and I could feel some weight coming from the shoulders. Down to Linn of Dee, then east along the river – on the north side to Mar Lodge. Unfortunately, the bridge that allows forward progress, just after the Linn of Qoich, was washed away, so I turned tail, passed Mar Lodge and took Victoria Bridge over to the road and then ducked into Morrone Birkwood National Nature Reserve, where some steep forestry tracks (which I was interested to ride as they form part of the Deeside Trail route) delivered me to Braemar, cold and admittedly a bit tired.

A pretty iffy burger and chips at the ‘the Hungry Highlander’ gave scant warmth and I headed further East, towards Invercauld and took to the trails after the Bridge of Dee on the south side of the river. I knew the woods here, where there are efforts to regenerate ‘Caledonian‘ forest, would likely give me a good spot to pitch the tent and turn in for the night.

Overnight, the rain fell and at one point, after attending to natures call, I tripped over the front dyneema cord of the tent and broke it, leading to a collapse and some rain fall wetting my sleeping bag. After scrabbling around for the peg I had pulled out with my clumsiness, I eventually got everything ship shape and retired again.

Then the grunting started.

I suspect it was a stag and at one point it came very close to my tent. I was curious to see if it would come into sight but after about 30 minutes or so it must have wandered off somewhere.

Due to the broken nature of my sleep, I arose late and so it was 8.30am before I got going. Another reason for my lassitude was the rain, which had continued into the early part of the morning and I was loathe to get going until it stopped. It did and the smell of the woodland as I neared Balmoral was beautiful and invigorating.

The low cloud was beginning to rise and, taking to the steep road after Crathie, I climbed north, feeling that getting to Corgarff Castle represented the 3/4 point of the ride. It was interesting to see the estate track heading back west towards Loch Builg off the B976 and I nearly took it, but figured I would stick to my planned route. At Corgarff, I turned off the road and dropped to Inchrory Lodge and then sped north, beside the mighty River Avon, with cloud and rain at my heels. At Tomintoul, I bought a couple of sandwiches at the post office, answered some surprised locals questions about the fat tyres I was running, and made the turn to the west where the hop scotch down the Burn of Brown was considerably easier than in previous times due to the fat tyres.

Climbing over to Dorback Lodge gave an opportunity to refuel and I considered my strategy for crossing the Dorback Burn. At times, this can run quite fast and deep, but at lower Drum, I found the ford which has been created there to be rideable. Unfortunately, the rain had finally caught me and soon I was both cold and wet.

Unfortunately, the trail after the ford dead ended ~500m away from the trail to Eag Mhor. At this exact point the rain became considerably heavier. It is difficult to explain how hard the ground between the ford and the Eag Mhor path is to cross. Deep water filled clefts between Sphagnum moss clumps and huge tussocks of grass. Still, before too long I made it to what I consider the exit of the Eag Mhor, at which point the rain stopped and I climbed into Abernethy Forest, taking a stallar singletrack that wound through the trees and popped out at the Lodge, where I made the turn for Ryvoan, it’s famous bothie and the completion of the route.

A block of cheese and a handful of Mike-n-Ikes saved me from a bonk and I dropped to Glenmore Lodge with relief to have covered the ground and having enjoyed some classic trails, superb views and another rewarding Cairngorm loop.





11-46

3 10 2016

Shimano recently released a CS-M8000 11-46 cassette. It is 11 speed at the XT level. It works with GS (or SGS) derailleurs with one ring at the crank and also DI2.

It is a nicely made cassette. I didn’t weigh it but the ‘heft’ would suggest it is about 100g more than an xtr cassette. Maybe more.

But you gain 6 teeth in range!

It is well made with aluminium carriers for the larger rings and fitting was palaver free: it just required a few turns on the ‘b’ tension screw to make it all work. Well, that and an extra 3 links as well over my 11-40 xtr cassette.

In use, it shifts without issue, on demand, in a very Shimano way: ie: fuss free, there when you need it even shifting smoothly under significant duress.

The range, with a 27.5×3 wheel and 32 ring is fantastic. It is a significant improvement over 11-40 or even 42. I was riding, loaded, up Coire Cas in the Cairngrom without much issue.

Recommend checking these guys out – Shimano quality, large range cassette with superb steps in gear range.





As the seasons ebb and flow.

24 09 2016

It is Autumn now. The daylight is retreating and the ground is becoming waterlogged and thick with fallen leaves.

I wanted to head towards the coast, for some reason. Lacking imagination for more interesting challenges, I took the Vertigo fatty, temporarily shod with plus wheels, to the Ardgarten loop.

It is not a particularly challenging loop, though the initial climb. westwards, followed by the climb up Glen Croe will keep your legs honest.

The trail over the Duke’s Pass is singletrack and at times offers a bit of challenge, particularly if it is as slimy on the rocks as I found it, but the views west are what took me there.

I probably ought to type something about my further exploration of plus tyres, as the fatty has allowed me to get time with a 27.5×4.5 a full 27.5×3 (on the rear) and 29×3 front and 27.5×3 rear. With interbike showing upcoming plus tyres from Maxxis that are on the knobblier end of the spectrum, *and* the growing 27.5×2.6 segment (which may well fit more 29″ bike rear ends), it is an exciting time.





Cost : reward.

29 08 2016

The circuit of Ben Alder is one of those ‘classic’ Scottish mtb routes. Kenny Wilson has a version as does Phil McKane.

The route typically starts at Dalwhinnie, tracking alongside Loch Ericht, until Ben Alder lodge, before climbing towards Loch Pattack and then Culra Bothy, which is now closed due to asbestos.

If you read any blogs or reports on tackling the route, it is rare that the side of Loch Ericht is utilised. Riders typically swing around the west side of Ben Alder, anti-clockwise, on the excellent Bealach Dubh singletrack, then descend Bealach Cumhainn to Ben Alder Cottage and then ascend, by means of steep, grassy, H.A.B, to the Bealach Beithe. The trail recommences alongside the Loch a’Bhealaich Bheithe, nestled under the east facing cliffs of Ben Alder, before dropping beside the Allt a Bhealach Beinnback, to Culra Bothy .

A different approach is to ride in from Loch Rannoch, climbing from Tigh an Uillt, into the Grampians cutting west then north to the southern tip of Loch Ericht, bog trotting to Ben Alder Cottage, then ascending north-west to the Bealach Cumhainn, then to Bealach Dubh.

Here, you stop, catch your breath as you take in the stunning view north, before descending to Culra under the watchful gaze of Sgor Iutharn and the impressive Lancet Edge.

From Culra, you can skirt Loch Pattack and it’s rickety bridge (if you ride it like I did, west to east, beware the ladder dismount) and drop on good quality estate track to Ben Alder Lodge. Then there is the simple matter of returning to Ben Alder Cottage via the loch side singletrack.

About that.

It’s hard going. I rode around 80% of it, but it is very rough in a low but sharp amplitude sort of way.

Then there is the sting in the tail.

On reading about the loch side trail, the ‘free style’ section around An Dun, which looks sternly down on Ben Alder Cottage, was something of a concern. The gate entry and exit are the least of your worries – they do not permit passage of a bike, you have to get your steed over the deer fence. It is the slippery, broken rock and loose grass and heather poised over substantial drops that give you the heeby jeebies. Indeed, about a third of the way around, I slipped, sliding towards a painful looking fall, before grabbing a handful of heather that arrested me and my bike mid calamity.

The cost of doing the route this way is high: the boggy section south of Ben Alder Cottage must be traveresed twice, the ascent to Bealach Cumhainn would be better as a descent and the loch side trail is hard going. However, the reward is the endless, peerless singletrack through Bealach Dubh and the hoot of a descent to Culra. It went on for ever.

Stats and kit notes.

The route, including 8km or so alongside Loch Rannoch to and fro, took me 7.30. I would class it as a strenuous route, not to be taken lightly with iffy weather. I think it would be best to miss the Loch Ericht trail back and try and put together a bigger loop, out by Dalwhinnie, perhaps returning to Pitlochry and making it a 2 dayer, or even to Feshie and back through the Gaick or Minigaig.

I rode my Vertigo cycles hardtail and the 120mm of suspension was welcome, but I think plus tyres would have aided the sections of boggy riding and perhaps allowed a little more comfort on the Loch Ericht singletrack.

I carried a 2L bladder and a water bottle and slaked my thirst at several of the gushing streams that pour down into the Loch when I ran short.

I used the Gaia GPS app on my phone for navigation, downloading the map as there is no signal in the area and it worked perfectly, yet again.

Two riders had completed this same route ahead of me. I was a little surprised about that as the ‘traditional’ route is used frequently. Goes to show…