bikemig 

One possible (and serious) downside to a 700c to a 26 inch wheel conversion is that your crank arms may clip when leaning the bike into a curve. You may be OK since you are running really fat tires but this is something you want to keep an eye on.

corwin1968

Definately. One of the reasons I put this bike on the back burner was that I planned to buy a set of Compass 26" x 44mm tires and that would be pushing BB height too much for me. Then Jan announced the 54mm Rat Trap Pass tires.

Fortunately, I have always intuitively kept my pedal up on the side I'm leaning toward and I don't pedal thru sharp turns. BB drop is surprisingly hard to measure and I've measured this one at 60mm on several occasions, although based on Trek's listed BB height with 38mm tires, the drop might be more than 60mm. The Ravn initially was spec'd with 70mm of drop but then it was changed to 65mm, which gives a theoretical BB height in the mid 27cm range, which is probably similar to my old Trek with the 26" wheels.

rhm

I did that.

The frame was an old Lambert Grand Prix. I like short crank arms anyway, so I used 152 mm crank arms. Both hubs were Sturmey Archer drum brake hubs, the rear one a five speed IGH, the front one a dynamo. The tires were Panaracer Pasela 26 x 1.25, so maybe that was the problem. It all worked, but there was no magic to the ride. I later rebuilt that bike with 700c wheels.

XXLHardrock

Awesome, now, maybe that high dollar set of P35/559 disk wheels, complete with SON Dynamo collecting dust in my garage will find a nice (all) road frame to roll with. Personsly I quite enjoy looking at that awesome 685mm diameter of the 60/559 Big Apples to say nothing of the ride quality.


It's kinda funny though, seeing 26" being touted as a cure for something when 650B was supposed to cure whatever just a few years ago.

green79

One option for a new build using these tires: I'm using Soma Wolverine converted to 26" wheels. I have a somewhat unhealthy obsession with smaller, wider tire conversions - I have a 700 road bike converted to 650b x 38mm and a Surly Big Dummy converted to 24" x 2.35" wheels. A big plus for me is increased standover clearance - I'm 5'6" but with a short inseam but long arms.

Clearance on the Wolverine is fine for me - BB height of ~265 with 165 cranks on a 50cm frame. It's going to be an XO 1 style build (silver components, flipped Nitto albatross with white bar tape) mixed with newer tech (belt drive, Alfine 11, dual piston disc brakes).

dwmckee

Is Jan sort of the "Martha Stewart" of biking? I get his magazine and my wife used to get Martha Stewart Living and the similarity just hit me....

unterhausen

How does that fit? Do you have any pictures? I just test fit a 26" tire on a 29'er frame, and it's just ridiculous. I got this frame because it has broken chainstays, and I'm thinking about replacing the rear end for 26" use

green79

I'm mid build at the moment and still waiting on some parts. Give me a week or so and I can post some pics. What was ridiculous about the test fit?

unterhausen

huge clearances between the tire and frame. The wheels I used had my winter studs, so the tires weren't the biggest.

catgita

I think Jan would like my rando bike a lot, if he were 2 meters tall and 100 kilos. Low trail (30mm), and tubing as flexy as I could get in the needed length, but still a tad on the stiff side. The formula works, extremely well for me.

It is interesting that both high trail and low trail advocates describe their preference as the "more stable" direction. I now have two bikes with low trail. Both are extremely stable, precise, and change direction easily. Not true at all of any of my high trail bikes.

My Zinn built with double oversize steel was stiff and horrible. My rando, on paper, calculates to be half as stiff, and is way more fun to ride. My 90s era Cannondale 2.8 was a harsh riding noodle, and scary as hell.

I often wonder how many people, given the chance to ride the range of flexibility that Jan, or even I have, would arrive at a fair bit of flex. Custom framebuilders very often do. Carbon bikes certainly could be way stiffer than they are. They too have more flex than people realize.

rhm

When it became clear that the Ravn was not to be, I built up this old Univega MTB frame as an 'enduro allroad' bike:



The bb height is pretty extreme, especially since I prefer shorter crank arms, but that doesn't matter except for when I stop. The Cro-Mo frame is very heavy, almost twice the weight of a butted 531 frame. The fork is fully double the weight of a 531 one (but it looks cool). Clearly a stoutly built frame, and though it gives me access to roads I can't ride on thinner tires, I'm still wanting a lightweight flexible frame.

ayjaydee

seems to me light tubing will "ding" pretty easily when ridden on gravel

rhm

It is probably easier to dent it in general, so you may be right; but in my gravel riding I have not noticed rocks flying up and hitting the frame, so I don't really see how this would be an issue.

unterhausen

I don't think I've ever gotten a ding on a bike frame from gravel, but there is always a first time. I probably get more sticks than gravel flying around. Even on gravel group rides, I don't recall too many instances of flying gravel, and we have lots of it

Also, most lightweight steel bikes are made with heat treated tubes, so they are more ding-proof

green79

Here's the Wolverine I just built up. This is a small frame (50cm) so the smaller wheels don't look too weird. BB height is 267. Fork is uncut until we get my dad set up on it. Front wheel will get replaced with a dynohub.

www.flickr.com/photos/69421720@N02/22048363642/
www.flickr.com/photos/69421720@N02/21437939624/

ThermionicScott 

Bet that's a cushy but responsive ride. And the 650B wheels really do help with the proportions. Thanks for sharing.

NormanF

Jan Heine is an asshat. He should have given due credit to Grant Petersen of Specialized who designed the world's first all-enduro bike for Specialized with 26" wheels as the standard. It was called the RockCombo:



It was the first attempt to build a do-everything bike with a road bike geometry and clearance for fat tires. It was a commercial flop as only 500 of them were made and Specialized dealers found them a hard sell.

The RockCombo in many respects was a bike ahead of its time and laid the foundation for what later became known as the hybrid bike. When Petersen moved on to work for Bridgestone, he did the same thing with the XO-1 bike but with the 700 C standard. Another flop at the time.

But today they're recognized as ground-breaking bikes and while the RockCombo is largely forgotten due to its rarity, the XO-1 designed for Bridgestone came to acquire a cult following.

LesterOfPuppets

Meh. Specialized/Grant Petersen can only be given credit for trying to bring some of Charlie Cunningham's ideas to mass market.

Here's a rig Charlie finished in 1979:

jfowler85

This seems less like evolutionary change and more like a marketing attempt to carve out a niche where one need not exist. Barring specific specs, the same thing could be accomplished by giving gravel/adventure bikes lighter materials, or just changing the current gravel/adventure lineups to include performance models at the top end. A carbon cx bike could easily fit the bill as well.

The market space doesn't need to repeat the growth of "craft" beer.

bikemig 

Did Peterson work for Specialized on the rockhopper before moving to b'stone? This thread suggests otherwise, 2 Wheel Fetish: Drop bar mountain bike redux: A vintage find, the Specialized Rock Combo, circa 1989

In any case, the bridgestone xo-1 was built around a 26 inch wheel, not a 700c. I own a 1993 bridgestone xo-2 which has the same geometry as the xo-1. It's basically a road bike built around 26 inch wheels. It's a really neat design for an all around bike and the bike rides great: