Thursday, April 17, 2014

Budget Pugsley Fat Bike upgrade to 9zero7 with Origin8 rims and Vee Rubber TIres

I first saw a Pugsley at New Moon Bike and Ski shop of Hayward, WI in 2009  when I stopped by on a vacation. When I got home to Alaska, I decided to look into getting a Fat Bike. I choose the Surly Pugsley frame because it was the only production Fat Bike available in those days.

I liked the idea of using an internal geared rear hub for the build because it would eliminate the problems of a rear dérailleur clogging and freezing up with snow. I checked with a rider in Whitehorse, Yukon who used one and confirmed it worked fine at below zero temperatures. Plus, it is sealed so there is much more protection from gunk. Lastly, it allows greater width to your tires because the chain never moves in and out like on a derailleur-equipped bike. I used a Shimano Alfine 8-speed hub and had Universal Cycles in Portland, Oregon build up a set of wheels.
Shimano 8 speed Alfine; they also make an 11-speed version now.
No derailleur, thank you very much.
When the Surly Pugsley was designed, the classic 100mm width of most all road and mountain bike front hubs was just not wide enough to accommodate the huge tires the fat bike used. So they cleverly used a standard rear 135mm single-speed hub, and did not put any cogs on it for the front. If you were really going on an expedition you could indeed use the front as a spare for your rear hub in case of trouble. But this makes the wheels a little tough to build because the rear hubs are offset to allow for the extra space the cogset requires. So, a front wheel using a 135mm rear hub needs to have some adjustments in calculating the spoke lengths with normal spoke calculator tools. The newest generation of Fat Bikes offer normal symmetrical wheels using newly-offered wider hubs for front and rear.

The largest Pugsley frame available had only a 15cm head tube. The head tube measurement is about the only way to compare the size of modern frames with sloping or very curved top tubes. I am 6'2" and have always had a hard time finding mountain bikes that fit and the Pugsley was no exception. The largest they offered was too small for me.

My mountain bikes have always been very uncomfortable to ride on the road because they are so small.  The position works OK on single track and I never ride on cross-country courses - only single track. I have been inspired by RLove2Bike's blog because he rides all winter anyway he can. I would like to use the Fat Bike to get out on the roads in winter when the trails have too much snow. Also, I really need more flotation on the trails, hence wider tires are in order.

So I decided to do some research on upgrading the Pugsley. First, I needed a taller frame. I looked at the websites of all the major Fat Bike players and, just like before, even the so-called "Extra Large" frames were too small.
Here is a list of a few sample head-tube sizes:

Surly PugsleyXL            = 15cm
Salsa Mukluk  XL           =14cm
Salsa Beargrease XL    = 15cm
Borealis Yampa XL        =16.5cm
Specialized Fatboy 21"= 15cm
Trek Farley 21.5"          = 12cm
9zero7  135mm              = 17.5cm

For comparison, my road bikes have 22cm head tubes. Now, I would never expect  my mountain or fat bike to have as tall a head tube as my road bikes but 15cm or less is too small. So the 9zero7 was the largest and a significant increase over my Pugsley. I needed compatibility with my asymmetrical Pugsley so I choose the 9:zero:7, which is asymmetrical like my Pugsley, and I could move over all the parts, except for the seatpost and headset.

Did I mention how cheap I am? Being retired on a fixed income I need to always look for the best solution at the lowest price. I used Surly Endomorph 3.7" on my Pugsley and wanted to try a wider tire on the upgrade to get some more flotation. When I looked at the price of Surly Bud's (26x4.8") I almost choked. I paid less for my car tires than a new Surly Bud. So I looked for an alternative. I found the new Vee Rubber Snowshoe which is the first bike tire to use silica compound to aid traction in snow. It is nearly half the cost of the other wide tires available. I picked up a pair from Chuck's Bike in Vermont. They look like nice tires but on 80mm rims they only measure out to about 4.1". So, I will watch for the new Vee Rubber Snowshoe XL, previewed at, which is supposed to be wider and available soon, because I really need a wider tire.

The new Snowshoe XL

To gain the full capabilities of wider tires, I need wider rims. I could run the new wider tires on my original Large Marge Surly rims but at only 65mm wide I would not get much, if any, increase in width over the Endomorphs. So, I looked for new rims to widen my outlook. Once again I was taken aback by the cost of 80mm and 100mm wide rims. After searching around I found the new Origin8 Pro 80.

Origin8 AT-PRO80
This rim can be used for asymmetrical or symmetrical wheels. I have built many sets of wheels but never a set with asymmetrical offsets. So I used this guide from the Golden Bike Shop to get the spoke length calculations correct.

Here is my score, a two-year-old XL 9:zero:7 in very good shape. I almost always buy used because the technoweenies always want the latest and greatest which makes their hand-me-downs a great bargain.

Next the build....

Got the front wheel built. The spoke length calculations from the Golden Bike Shop above were right on. It is a little strange building it because the spokes are all in a line. The wheel doesn't really take shape until all the spokes are in place. Seems like it is not going to work until that point.

100mm BB is moved over from the PUG.
Brakes moved over...

Replaced the outer ring with a chain guard since it is not used...

Rear Wheel laced up and ready to true:

Part Two of the Pugsley upgrade:Pugsley to 9zero7 upgrade part 2


Gunnar Berg said...

"hand-me-downs a great bargain"

That explains why my "new" hand-me-down Cambio Corsa Galmozzi was so cheap.

biciak said...

Ya well there are exceptions to every rule!

Adam Jay said...

I've built a 2nd wheelset from the Or8 AT-PRO-80 UL rims. Very great, all around rims. I couldn't be happier.

biciak said...

I agree Adam, I can't say how long they will last but I am quite satisfied at this point.

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