Chainline versus cinch.

9 05 2018

A few years ago, I started running Race Face Next SL, SIXC and then Turbine cranks. The weight and low ‘Q’ factor of the Next are pretty awesome, but I (like others) have had a crank axle insert come loose. Others have had pedal inserts come loose: but, I do have 3 sets on the go which have been fine so far. I am always messing around with things and the shared axle crank interface between Cannondale Hollowgram and Race Face Cinch has had my attention recently. The Hollowgram SI are within grams of the Next SL and may be a reasonable alternative whilst retaining the unbelievable versatility of the Cinch.

A case in point.

The Turbine has a few millimetres greater ‘arm’ offset than the Next SL and I had a use for this. My 44 Bikes ~TNT~ had a Saint crank. The reason was the 83mm BSA shell (mated to a 150mmx10mm thru QR rear hub). There were only so many cranks that were available in this width and this width works well to get short stays and good ring clearance with 3″ tyres. It is a sturdy crank to say the least and the arms are quite bulky. I had been getting some medial knee pain on riding the 44 and I had isolated it to the crank.

On my Vertigo Cycles Kraken, Sean machined a SIXC 83mm crank axle so that the Next SL cranks would fit and work with the 177mm rear end. This used a flipped ring and thus gets a great chainline despite the ‘snow bike’ width rear hub.

A quick note – most geared bike set ups are biased to the smaller rear cogs. This is essentially to get stay/ring/tyre clearances in the manageable bracket. However, there is an argument that the ring should be more inboard at the front for todays gear spreads. Some manufacturers had started to address this when 1x systems became popular, offering aftermarket rings that were spaced to be slightly more inboard than usual.

Then, of course, rear hubs started getting wider and ‘boost’ then ‘super boost’ happened. Sean has been guiding me for years on this sort of thing and the bikes he has built for himself, others and me have often used 150 mm DH rear hubs with either flipped rings on 73mm shells, or ‘normal’ ring position on 83mm shells and as time has progressed and ‘plus’ tyres happened, moved even wider with flipped rings on the 83mm shell equivalent widths and 177mm rear hubs.

Phew.

I had been wondering about converting the 44 to the Cinch system. Interestingly, Race Face – perhaps due to the proliferation of 157mm “super boost” rear hub selection by several manufacturers (very sensibly, I might add – I have been advocate since 2010) – had quietly released a 143.5mm crank axle and also a 149.5mm axle for Next SL. The latter is equivalent to an 83mm BSA shell – the usual standard for a 150/157mm rear end – and had previously only been available in the DH orientated SIXC. The ring would normally be mounted in the inboard biased traditional position.

But you will know that often, direct mount rings can be flipped, if they are round, and there are different offsets of rings. The ‘normal’ is 5 ish mm towards the bike midline. Flipped, it is 5 ish mm outwards Why ‘ish’ ? well, different brands – a list would take too long – use a different offset – from Race Face’s 4.5mm to Absolute Black, Wolftooth and IIRC One Up using 6mm. There are others, but these are probably the major players.

Then there is Boost offset – usually around 3mm less. Soooooo….

If I took the BSA 83mm shell, which utilises the three 2.5mm spacer rings, which normally uses a 149.5mm axle equivalent, bought a 143.5mm axle (designed, most likely, for 148mm rear hubs?), removed 2 of the spacers (take away 5mm of the 6mm difference) and fitted BSA 30mm bb cups, a boost ring (add 2mm back to the chainline which with the shorter axle was 1mm more inboard) and the larger offset Turbines, I reckoned I would get great chainline and get the stay clearance and a slimmer, lighter and therefore more flexible crank on the bike.

In short, it worked.

This stuff is a minefield. I have another bike I want to do something somewhat similar with – my Vertigo Maul. It has a normal 73mm BSA shell, and I am going to use Cannondale Hollowgram cranks with (I hope at least!) a Wolftooth FAT CAAD (listed as -1mm but it seems to be more like +1mm) CAMO spider so that again, I can get a great chainline biased more inboard for the 150mm rear end on the bike.

I have been collecting data on all the different spiders and DM rings around, but the listed offsets are often either hard to find or seem wrong on measuring and thrown together with the different ring mount positions on different brands of cranks, different crank arm offsets and requirement for spacers etc, you need an obsessional trait to try and make it work. My advice? have the bits in hand, measure and then work out if it will fit. The downside is simple – cost.

But, with all the interplay between Cinch kit, Hollowgram and SRAM cranks (which have even more standards for where the ring mounts) you can make an über sweet, bespoke crank work on most bikes and get great chainline.

The bummer is giving myself a reason to pull King BB’s out of frames. Chris King deserve an award for making a bb that is seemingly impervious to scottish weather – no small feat!

Ok – this was probably as hard to type as it was to read and digest. If I have made any mistakes, I will correct them and fire away with questions if you are interested.

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Everyday carry.

11 05 2015

Sorta.

Everyday carry is, I guess, a meme. It is an interesting concept. I got to thinking about it while I was preparing to head off for a short bikepack the other day. What is the essential everyday carry ? how does this sit beside what would provide a slightly more comfortable existence on a short bicycle tour? everyday-plus, if you will?

So, I decided to have a closer look at what I carried on a ‘heavy’ trip and perhaps dwell on the contents a little. Heavy is in inverted commas because I wouldn’t necessarily class the contents of my bags as heavy per se. But I most certainly brought some non-essential items (depending on your point of view. of course!).

So, here we go.

Let’s see, starting at the front, a Revelate small front pocket for a Sweet Roll. Inside, essentials I might need to grab at short notice or, perhaps, when it is getting dark.

Opinel, ti tent pegs (2 sorts for different ground conditions), Sinewave Revolution – an amazing gadget covering all my charging needs from the Son front hub, Steripen freedom, notebook, Snow peak ti spork, a dyneema cord with cord lock, fire steel and spare lithium batteries for the Etrex. Not pictured, a few notes and a bank card and my keys.

Under this, of course, is my Sweetroll (not pictured). In this, I have my tent (a Mountain Laurel Designs Cricket), a Patagonia nano puff, and a spare inner tube (varied with which bike I am riding – in this case a Bonty 2.5-2.8 26″) and a Z-packs UL carbon fibre tent pole (that folds down into a short 40.5cm packed size). Often, CF poles can be flimsy and if broken can pierce tents. In this case, the joins are reinforced with tyvek tape. It’s been solid.

Behind the bars, I use 2 Revelate feedbags.

In the right one, I carry food. Mike n’ Ikes, cheese, pork pies, clif bars, granola squares etc, whatever I pick up along the way.

In the left, I carry my cooking kit and some sundries in the outer pockets, in this case my toothbrush, paste and chamois cream.

The cooking kit consists of a ti mug from MSR and an MSR gas canister (for the MSR Pocketrocket I keep in the Wingnut lumbar pack). I use an MSR Mugmate for coffee – works extremely well. I also store TP and a few sheets of kitchen roll in bags to a) stop rattling and b) use.

Next, is the Gas Tank – again, food.

Lower down, on my 44 bikes fork, I have 2 water bottle cages.

The Steripen needs a hard water bottle for use, I tend to take at least 2 and in the other cage I use a Specialized Keg. This doesn’t contain beer, but it is a useful little ‘hard’ storage for (in this case) my Niterider head light, extender cable, some wipes (one thing that is distressing is the number of wipes I see discarded by the trails. They don’t biodegrade fast at all and this is making a huge mess in some well travelled areas) and cotton wool/vaseline for fires, if needed.

Next and also unpictured, is my Viscacha seat bag. In here, my sleeping bag (PHD), Thermarest Neoair, wool longs and a R1 fleece with hood.

Lastly, I have my Wingnut.

In this, I carry a 2 litre camelbak bladder, which I try to use minimally – basically to lessen weight on my back. I also carry my MSR Pocketrocket, Gerber essential utility knife, Lezyne mini pump, another tube, coffee, Patagonia Houdini, Niterider battery, camera stand, some whisky (in this case A’bunadh) and a midge head net. I usually take a freeze dried meal of some sort. The little, old Timbuk 2 bag is my tool kit.

In this, levers, folding chain tool and quick links, 7075 Paragon hanger, Stahlwille 12 point drive socket and driver for the ti bolts on the Paragon sliders, Genuine Innovations CO2 head and cartridge and also a tubeless repair ‘worm’ kit. In the ziploc bag I carry assorted bolts and a home made tyre-boot set – with sticky stuff and sail cloth and also quick patches. I also carry a small bottle of Squirt chain lube. Some of this is extraneous, but I tend to leave it as-is so I can grab and go no matter which bike I am riding.

Various items are stored in some MLD cuben bags.

For the real nerds, the weights (bag + contents, food items to use for 2-3 days included, water not included):

Viscacha – 2kg
Sweetroll – 1.55kg
Cooking Feedbag – 0.5kg
Gas Tank – 0.35kg
Food Feedbag – 0.6kg
Front Pocket – 0.85kg
Wingnut – 3.5kg

Total weight – 9.35kg.

It seems heavy, when toted up like this, but a lot can be pared away if I am prepared to have fewer creature comforts. The bike rides extremely well with this set up.





Breaking news.

19 07 2014

Rather unfortunately, after 2 hours of use, the Thomson dropper doesn’t seem to want to return to full height anymore. You have to give it a pull and there seems to be very little pressure in there. I suspect a nitrogen leak (the hydraulic cartridge relies on a nitrogen charged spring in the Thomson: it is not user serviceable). I suspect I probably jinxed myself by vocalising the fact I had waited for a good few years for these devices to demonstrate reasonable longevity. Anyhoo. Back to the shop and we’ll see what happens.

So just to cement my position as a paying beta tester, I got this to mess about with…

The 44 is getting lower gears. I do ok with 32 – 11-36, but there is no doubt that when loaded, with those big and relatively heavy tyres, it can be hard work. So…we’ll see.





Ben Venue.

20 06 2014

It has been a while since I ventured up Ben Venue. A lot has changed! My aim for the day was to get over the shoulder of Venue, then drop down to Kinlochard and head into Queen Elizabeth Forest, nip round to Comer and then over the shoulder of Ben Lomond, and take the West Highland Way back round to Aberfoyle by way of Conic hill.

Riding through the forest from Aberfoyle showed me how dry the trails were after a lovely, prolonged spell of sunshine. The trail up Venue from the Duke’s Pass still starts by climbing through some fine forest, but the upper area has ben felled. This hasn’t been good for the drainage of the area and a lot of sections of the trail are rutted and washed out.

Once you get up into the corrie, climbing above the tree level, the path has been all but destroyed. Huge areas of bog, alternate routes that seem to have been trampled in at random and the clegs patrol the area in force. Still, I made reasonable time up to the ridge and followed the singletrack west. Unfortunately, the descent down to Kinlochard is an absolute mess. It took me forever to get down and the ruts could have swallowed my bike!

This put a bit of time pressure on me and as I neared Comer, it became clear I was going to have to turn tail and get back without completing the route. I’m not convinced I’ll be up Ben Venue for a while. The path is such a mess and I am unaware of any plans to improve it – it desperately needs some love! A shame as it would be a good loop.

Next up: putting a months worth of intensive UL/SUL solo shelter research to use…





95

20 04 2014

Sun is out, bike is built. Bags packed – not too carefully: live and learn is the name of the game.

Out through the woods. Bone dry trails – as if the last 6 months of rain never happened. My cold doesn’t seem to be slowing me down too much. Game on.

Take the well worn trail, along the West Highland Way. Too busy with walkers for the technical Conic Hill decent, around instead.

Then along the bonny banks. Not sure if I will go north or cut east. Take it as it comes.

Struggling to eat, energy is now coming hard. Llamas save the day, at least for the moment.

Snot is making me choke, still not eating. Water from a waterfall is reviving, but there are not many calories in H2O. Decide to head east, around Loch Katrine and instead of bivi’ing out, make for home to lick my wounds. My estimate makes it 100 miles by the end of the day. I’m ok with that.

In to Queen Elizabeth forest to wave at all the rough campers beside the wee lochs. Beautful day for a bbq and a beer. It just about makes my mouth water.

The dust is amazing. Forest trails slip by easily. As the sun begins to dip, the temperature does likewise.

My ‘disaster style’ packing left me with no arm or knee warmers. Shivering is on the horizon.

My Sinewave revolution has charged my light, just in case but I think I’m on for home just after sun down. Cut it close. Keep it tight, but loose.

With the sun gone, my mind flips to the negative. My left 4th toe is dead to the world again. I’m concerned about the fact it hasn’t got better over the last few weeks. My left knee feels a bit tweeked too.

I run over gear choices and thoughts. The new packing system – frame bag ditched, smaller pocket from Backcountry biking on the front of the sweet roll and two feedbags in place (cooking kit one, food in the other à la Paul Errington) – is much better and it feels lighter, but it is still heavy, in some ways. 5.5kg on the bike (bags and food included, water not).

I’m struggling to see how this can come down, although an Ermine on the way and my occasional-use-only cuben sweet roll will knock off a few hundred grams.

Home, pizza, beer. 95 miles in the end. 10 hours. Done for today.





T.N.T

14 04 2014

The 44 arrived today and before too long it was time to get building…

IMG_8713

it is good to take some time to build a bike so you know it is done *right*

IMG_8720

axles were swapped and the drive chain and brakes messed with…

IMG_8724

the wheels fitted, initially without tyres…

IMG_8726

so, more to do, but it is looking sweet as…

TNT – I’m dirty, mean and mighty unclean, I’m a wanted man, Public enemy number one
Understand

IMG_8727

more soon…or see more [URL]=”https://www.flickr.com/photos/drj0n/”%5Dhere%5B/URL%5D…





Progress…

27 02 2014

Photo’s are from Kris flickr, again. There are some more there as well.

I built up the front wheel. I was a little trepidatious regarding this build as the flange of the SON 28 front hub is 58mm and it is nearly symmetrical. This means that it is ideally built offset at the rim, side-to-side. The rabbit hole drilling is 7mm offset from center. this means there is not a great deal of triangulation on the spokes. Good, even tension will be critical for longevity.

It went ok though…good tension around 90kgf with 10% variation and <0.1mm lateral and radial. Fine for the rabbit hole rim.

Next step for me is to wire up the Sinewave Revolution to the hub and get all 1.21 giga watts…more soon.

And another thing: what on earth are folk using as a jig for building 190mm or wider rear hubs? answers on a postcard, please.