23 01 2016

Hodag action! from dRj0n on Vimeo.

Time to ride.

23 01 2016

Sloppy, slimy and slick. Thick mud and treacherous rocks. Teflon coated roots. It is winter, after all.

The hodag needed very little time to find it’s way to my heart. It rides lighter than it would seem. Feels kinda sporty-like. It replaced a chupacabra on a nextie 50mm rim so the weight gain is in the region of 360g or so. I never felt like I was struggling with the girth though. And the grip…oh the grip!

Those sipes and spaced out blocky tread make for a very secure front tyre. Granted, with a 45mm internal rim, the profile is round, but at 9psi I had bite everywhere I needed it.

The diameter is 20 mm or so less than the chupa. It *was* noticeable. The roll over a 29+ has is a boon. I missed it in some places. But the chupa struggles in mud…not so much on slick surfaces: the compound is great and offers security.

The hodag clears well and keeps coming back for more. It did not fold under and I suspect I will end up lowering the pressure a touch just to see how it feels, though it absorbed chatter and square edges with aplomb.

Yeah, like it.

Hodag, part 2.

20 01 2016

I got hold of the 46mm aluminium WTB presta valve, taped the rim with some 3M 764 and got busy with the airshot. BAM! up it went.

It held pressure with no sealant and at 25psi, the measurements are 745mm diameter, 87mm casing width and 93mm tread width. The casing appears to be around 68mm from rim edge to outer diameter, and 73mm if the knobs are included, but the accuracy of this is questionable as the vernier gauge was eyeballed. The rim is 45mm internal.

I will leave it overnight at high pressure and see how it stretches out and settles onto the rim. I am expecting the diameter to increase slightly given others’ measurements of a similar set up.

I think this is probably über plus, rather than fat.

Nextie Junglefox II build.

18 01 2016

As I mentioned previously, I am building a new wheel to facilitate the use of the Bontrager Hodag 27.5×3.8″ tyre. I chose a Nextie Junglefox II rim and decided to use DT Swiss Squorx nipples, Sapim D light spokes and lace it all to a Paul wHub. My reasoning for spoke & nipple choice was detailed in the linked post.

The build was uneventfully smooth. Notably, the nipple drilling now appears to be directional, offset 2.5mm and the Squorx nipples were excellent to use. The torx driver tool allowed me to very quickly bring the spokes up to a tension that was useful to start bringing the lateral and radial true in. I decided to go for just under 100kgf on this build. I don’t ever seem to have any issue when using this tension on the big cross section carbon rims. The balance was reasonable rather than very good: I had a couple of spokes that, seemingly inexplicably, ended up with either ~15 more or less kgf. Still much to learn, young padawan. The wheel is 2 cross – which I find works well for stiffness with the wide 82mm flange spacing of the Paul wHub.

Here are some pics.

Next step is to add the tape, a 46mm wtb aluminium presta valve and get that tyre dirty.

Snow Job.

17 01 2016

So, today I rode ‘Snow Job’, my Vertigo Cycles fat bike, in snow. I have never ridden a fat bike in snow before; plus bikes, yes, ‘normal’ tyred bikes, yes, studded tyre bikes, yes. It was fascinating how competent it was. Steep trails up, down and deep snow in tussocks of grass all cleared with ease. I even traversed a creaking, groaning ice-capped bog, though I lost my nerve after the sounds from the presumably thinning surface became more confluent.

The resistance was quite noticeable at times, particularly in deeper sections on climbs. Indeed, it took a noticeable amount of extra horse power to keep the speed up. Grip from the 45Nrth Flowbeist was inspiring and the Maxxis Mammoth on the rear surpassed my expectations.

I don’t know how long the snow will last, it seems to be wetting out and retreating generally, but I will try to get more time out shortly.


31 12 2015

So, the Bontrager Hodag. B plus plus? 27.5×3.8″ or about 93mm wide on a 50mm rim it seems. Diameter around 750mm or so (I *think* these are Walt Works measurements, but cannot be 100% certain, as I committed the numbers to memory, then promptly forgot the source).

I received the tyre the other day and decided that I would use a Nextie rim to build up the wheel: in this case a ‘new’ Jungle Fox II. I used a Jungle Fox previously, but the new one is 2mm wider at 52mm wide external, 45mm internal. This suggests a couple of extra layers of carbon sheet, as the bead edge is thicker. Probably a good thing, but they are still light for such a big rim. My previous experience with Nextie was slightly marred by the nipple drilling being off in several cases. Not enough to make the wheel impossible to build, but the longevity will definitely be affected. In saying that, the rims have seemed durable in use over the last 10 months – see my previous post for the first build with Nextie rims. Also, there are rumours they are using a different manufacturer and the drilling has been much more consistent recently.

Nevertheless, due to my prior experience, I am going to use a DT Squorx pro head nipple, that has a spherical interface with the rim hole edge, hopefully allowing a better alignment with the hub if any of the drilling is off. In addition, the Squorx head will allow for a safety net to let me tension the spokes if needed (poor drilling angle adds significant resistance to tightening the nipples during the build).

I am using Sapim D light spokes, 2 cross in this case. The hub is a Paul wHub, which is symmetrical with relatively high flanges and wide spacing; there is just no need for 3 cross here.

I used Freespoke for the lengths after measuring the ERD (as slightly larger than the 533 quoted on the website, which I suspect is the actual rim inner surface diameter). Freespoke has proven very accurate over the years: highly recommended.

Screen Shot 2015-12-31 at 15.21.21

More as the rest of the wheel parts arrive.

Bontrager Chupacabra.

14 12 2015

Mounting a new tubeless tyre on a wheel that has a well sealed tyre already in place is an exercise in overcoming inertia. How much better will the tread *really* be? Will it seal again? How much of a pain is it going to be to remove the old sealant and, maybe, tape? Will you need a compressor?

I finally got over the hump and removed the Maxxis Chronicle from my Nextie Junglefox front rim and got to work removing the old Gorilla tape and recalcitrant adhesive. For this I use isopropyl alcohol and a Good Grips ‘deep clean’ brush set. This brush is stiff enough to remove the old adhesive and the hard rubbery ‘poker’ can be useful at lifting really obstinate sticky stuff.

Next, I apply a new layer of 3M 764 vinyl tape. I spent a bit of time recently researching tape characteristics and this stuff is stretchy, sticky and it comes off cleanly should this be required. It is also damn near airtight itself. I get it from Viking Tapes and although the order minimum is 6 rolls, you soon start to use it up.

Previously I used Gorilla tape, as mentioned, which has two drawbacks. Well, three. It doesn’t come off easily – leaving a lot of residue. It also seems to become boggy with sealant in time, and is quite porous, so I tend to need to keep topping up my sealant. Okay then, four drawbacks: it is also h e a v y. The difference between these 2 tapes (one layer) is ~40g. Admittedly, the Gorilla tape weighs only ~60g, but functionally the 3M is better *and* lighter, so it is a win-win.

Talking of weight, the Chupacabra is 860g or so and the Chronicle was just over 1000g (for the non-exo version, in this case). So all in all I lose 200g from the front wheel.

A blast with the Airshot and BAM! up it went.

It has been far from ideal conditions to ride recently and I am only slowly feelign my way back to any sort of regularity on the bike, but I am looking forward to seeing how the 2 compare. Volume wise, there is very little in it.


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