Monday, July 6, 2009

Proto-bike


parts_on_floor, originally uploaded by melanthius18.

Here we have most of the parts that will become our cargo bike. The fork is that designed for the Surly Big Dummy, one of the other cargo bikes we considered. We went with the Mundo because of the greater cost of the Surly and reports of instabilities with very heavy loads. "The wobbles" were also a problem with heavy loads on the Xtracycle- converted mountain bike we used to have and it sounds like it may just be a problem with the modular rack design. I even added custom bolt-on struts between the seatstays and vertical racks of that bike to combat the problem, but we were looking for something stiffer this time around. The Surly fork, however, looks great. It's big, strong, and has a disc brake mount and rack braze-ons. It's also almost an inch shorter in crown-to-axle distance than the Surly Instigator fork that the Stouts use, so it should raise the top tube a little less than on theirs.

Also visible here are a pimpin' white Halo Combat rim for the front, along with white spokes for that wheel (the white hub hasn't arrived yet). The other rim is a 48-hole Salsa Gordo, the only 26" 48-hole currently available with a brake track for rim brakes. I'll be using a 9-speed cassette hub making the wheel more dished than with the modified BMX freewheel hub that Yuba specs on their 6-speed model, or any single-speed or internally-geared hub that only has one cog. I wanted a 48-spoke rear wheel to ensure the greatest strength with such a large dish, and the Mundo doesn't have a rear disc mount, so I also needed a rim with a brake track. This one is it.

Also visible is a 185mm Avid BB7 disc brake for the front and SD7 rim brake for the rear, matching levers, a Shimano LX Hollowtech II crankset with only a steel 32-tooth chainring and a bash guard in place of the big ring, a Brooks Flyer, a pair of Schwalbe Marathon Plus puncture-resistant tires (I'm a big fan of the Specialized Armadillo lines, but wanted to try these because they seem to be building a reputation to rival the Armas), and various other small parts in the bags.

Just waiting on the replacement frame and my hubs to put this all together.

7 comments:

MamaVee said...

Just a big hallo back at you! can't wait to see how the cargo bike comes out.

V

Kitty said...

You likely know about this event in SF http://bicyclemusicfestival.com/ which justed passed. yah?

inkandpen said...

Kitty,
I read about it on the Rock the Bike blog (the shop that sponsored the event)-- very cool! The Yuba Mundo was also heavily featured in the festival, and a version of it will soon be our new bike!

Julian said...

Curious ... new Mundo or old? If new, do you think it's as sturdy? There's some vague stuff online about the 2.0 Mundo being child seat compatible, and a photo of some 2 grey plastic Topeak-looking bike seats on the back of one on the Yuba site. Can't wait to see the built bike! You and the Stouts are making me give the Mundo another good look ...

melanthius said...

I'm working with a 2009 (new) Mundo frame. The rack certainly has less metal in it than the 2008 (old) model, but still feels plenty beefy. The seat-compatibility is from the new rack being narrower and being made from smaller diameter tubing so that a seat will fit over and fasten properly to it. Besides the changes to the rack, the frame looks fantastically better than the old one. The ovalized top- and down-tubes look great and the rear triangle is every bit as strong and stiff as you'd want. I'll take plenty of photos during the build.

Anonymous said...

Dave and Katie,
I am enjoying your blog, even though I don't speak bike. It is exciting to be creating your own transportation, isn't it?
momjude

Robert Davidson said...

What hub are you using - I have searched and searched for a 48 spoke 135mm OLD cassette hub with a 14mm axle without any luck at all.