Sunday, March 6, 2011

The 100mm experiment

Snow bikes were invented to provide more floatation than a standard mountain bike. It stands to reason that the wider the rim, the more floatation you will achieve as long as you have a tire that will take advantage of the rim width. My first snow bike, the Wildfire, had 65mm Large Marge rims. My Fatback came with 80mm rims. In my quest for more float, I just had Fitzy's lace up a set of 100mm FlatTop rims.

The old 80mm rims next to the new 100mm rims

The project is not quite as simple as relacing the hubs to new rims which is why I call this an experiment. The 100mm rims take up a lot of real estate in the rear of the bike and I am going to lose a couple of gears in the process. I am hoping to keep 7 gears but I may end up with 6 in the rear to go with my triple in the front. The FlatTop rims themselves are very average in quality so I am not sure about longevity. I will post more on the experiment once I dial things in a bit more.

Fat wheels bolted to a Fat fork. Phat!

Today was my first ride on the 100s and they are very stable. The additional width and change to the tire profile is noticeable. We were relegated to backroads but we did ride through 6-8" of fresh snow on the unplowed section of Stateline Rd and I broke trail easily. Sweet!

I really wish my Endomorphs would last more than one season. Running them at 4 PSI wears out the sidewalls long before the tread.

We had a great ride on Teton Valley backroads and were stocked that the precip remained frozen and didn't turn to snain...or worse. :)

This guy didn't wave back or smile when we said hello so we will call him 'Crusty' from now on. He did have a cool snowblower tractor though.

M wasn't having any fun at all.

Riding & Smiling

Even more smiling...

Yeah, we still have a LOT of snow here Teton Valley.


Eszter said...

Me want. Real-bad-like. :)

Vito said...

I'm running my Pugsley with 80mm Graceful Fat Sheba rims from vicious cycles as a single speed (30 x 22). I don't live in Idaho and I'm assuming that an ss set up would not be the best option in your neck of the woods for a snowbike.

I do love those drilled out 80s you have.

FixieDave said...

should have waited to post this till FAT Tuesday =)

Anonymous said...

what, no front brakes!

spruceboy said...

I am using 100mm flat tops on a 2010 alu fatback and only had to lose one cog on the back.

Dave said...

Eszter - have you called Walt yet? :)

Vito - a singlespped would be great here...for long walks with my bike. :)

Spruceboy - your 170mm rear end vs. my 165mm rear end is probably just enough to gain you that extra cog. My wife has the 2010 Alum Fatback and I really dig it.

Anonymous said...

The Larrys have a 120tpi sidewall compared to the 60tpi of the endos. Just a FYI

spruceboy said...

How well did your endo and larry mount on the 100mm flat tops? I had a bit of trouble getting the endos bead properly seated on mine. It was quite a pain actually, though it might have been user error on my part.

Dave said...

Spruceboy - the fit of both tires is very loose, borderline unacceptalbe. I am going to try wrapping two layers of Stans tape or Velox next to each rim's inner wall to build up the diameter a bit. I will post the results.

Speedway said...

This is the reason that I did not release my Uma 80's. They made the mold too small, though they are still bigger than the Flat Tops, I had to reject it and start over. Tire width on those rims was over 98mm.