Saturday, November 28, 2009

more about the pugstigator

In a recent post, I introduced the Pugstigator, which is the bike I've been riding everywhere for the past week. What is the Pugstigator? The frame is a Surly Instigator. While an Instigator fork is available, the Instigator frame is sold without a fork because Surly assumes that the user may want to use a suspension fork, or any other after-market fork that is deemed appropriate. In this case, it was deemed appropriate to equip the 'gator with the symmetrical version of the Pugsley fork and a symmetrical wheel built on a Large Marge rim with Endomorph tire. The Instigator is rated for a 2.7" tire in back, which seems skinny compared to the front tire, but it's still pretty fat. I am using a WTB Moto-Raptor tire with a nominal width of 2.40 inches. The whole bike weighs 36 lbs, which is amazingly close to what my other bikes weigh.

I should point out that the Instigator frame is not a requirement. Almost any bike that takes a 1-1/8" steerer can be retrofitted with a Pug fork and wheel. The point of all this nonsense is to create a Pugsley-esque bike without buying a Pugsley frame and the special offset rims that are made for it. Simply by removing the Pug wheel and inserting a "normal" front wheel, this would become a typical-looking rigid MTB.

How does it ride? The big tire is actually lightweight and "supple" for its size, and at "high" pressure of 18-20 psi, does not feel slower than any other high-quality offroad tire when ridden on pavement. It's not a road bike, obviously, but it rides way better on the road than a road bike would ride here:
Pugstigator on the Mississippi
In fact, I could envision myself doing long distance (100+ miles) on this bike, though I'd be unlikely to set any speed records. On pavement, this rig has good momentum, and is very stable-feeling. I can ride indefinitely with no hands easier on this than on my other bikes. I think this has a lot to do with the high bottom bracket, but I'm not 100% sure.

One feature of the Pugstigator that is new to me is hydraulic disc brakes (Avid Code 5). I've always found mechanical discs to be effective enough, but somewhat fussy to use, noisy, etc. The hydraulic brakes are a revelation, and I doubt I'll ever want to use mechanical disc brakes again. They are smooth and quiet and not bedeviled by the various friction issues surrounding cable-actuated brakes.

Yesterday I was out testing the capabilities of this bike by riding on rocks and sand along the river, and even down a small set of stairs at the Veterans Home. I found out that reduced tire pressure makes riding here easy and enjoyable.
Pugstigator on the Mississippi

The reduced tire pressure that works well on rocks and sand and other irregular or shifting terrain makes for an unnerving experience when riding on pavement or hardpack. The squishy tires dive unexpectedly into corners, while, with just a few more psi, they carve the same corners with a feeling of security and some degree of controlled precision. It's amazing that a mere few hundred strokes of the mini-morph pump can produce such a large disparity in capability over diverse terrains.

Finally, after all this, the casual reader, like many visitors to the shop, may be tempted to ask "why?" or "what's it for?". I REALLY hate to get into the asinine practice of pigeonholing bikes into marketable categories. That said, I like to think that almost all bikes fit into my loose definition of "touring bike", which is: a bike that one can ride to experience the world, look at scenery, hear noises, smell the local cuisine emanating from kitchen windows, etc. All touring bikes have design trade-offs. A Long Haul Trucker loaded with 80 lbs of camping equipment and food is a poor choice for 150-mile day tours, but a 16-lb race-geometry bike that can accommodate only 700x25 tires is a generally poor choice for multi-day self-supported camping trips. Somewhere in the spectrum of bike touring, there is room for a bike that can travel comfortably and safely over any terrain that even remotely resembles a road or trail. As can be seen from some of the photos, I have been tinkering with various bags on the bike, with the ultimate goal of actually taking this bike on multi-day multi-terrain tours with camping gear.


bloodline said...

when i was mountain bikling everyday i sometimes enjoyed low pressure in the front tire for a 'suspension type' feel....i used to ride my 'work bike' downtown chicago with a 35X700 in the front and 23x700 rear.... how does the surley company feel about this bike, i bet they may like it...

MplsMTB said...

You should start having Pug rides from the shop! You'd be surprised how many fat bikes there are in S. Mpls.

I have a similar set-up as the Pugstigator... except I used a 1x1 frame. Here's a link to mine. A 100mm Pug fork and an Ednomorph tire were added this summer. I'm running it as a singlespeed now.

If you chop the brake bosses off the Instigator, you could probably run that 2.4 WTB tire on a Large Marge rim.

Jim Thill said...

The problem with going with a wide rim/tire on the back is that the chain will rub the tire in the lowest gear(s). I have a few ideas for working around that, but for now I'm going to keep a normal rear wheel on it.

MplsMTB said...

Alfine hub?

By the way, I LOVE the Pugstigator! Makes me wish I had gone with an Instigator instead of a 1x1.

KM said...

Karate Monkey (aka Pug Monkey) is a great choice too.

doug peterson said...

Is the Pugstigator coupled to facilitate travel to warmer climates? Oceanside can look mighty good along about February!

Doug Peterson

KM said...

I think the folks at Brompton should make a folder version.

Scott G. said...

Have you used this on the snow yet? Curious how this set up compares to the "true" fatbikes on the snow, also have an instigator and am trying to figure out what direction to go with it.

Bujiatang said...

Scott, this may be info coming late, but I also have an instigator. I used an enabler fork and use a Larry in the font. The bike is brilliant on single track and a dream in snow.