First there was a question and I had an answer:
From firstname.lastname@example.org cargo bike listserve,
"I'd like a tire that can handle some off-road/gravel/hard-pack/maybe some mud, but which will also be fairly low rolling resistance on the the street. Right now I think my Xtracycle will see mostly street duty, but I'd like to have tires on it that will serve for those times that I might ride on the rough stuff. Also, after seeing some blog posts by a guy who uses his Big Dummy to carry equipment out to his research sites, I've been inspired by the idea of maybe using my Xtracycle to get out to do camping, birding, carrying my boat, etc."
So replied with this,
As a guy who has written "some blog posts by a guy who uses his Big Dummy to carry equipment out to his research sites" I'll throw my two cents out there.
(I don't know for sure if it was my posts that you read or not, but if there is somebody else hauling research equipment with a Dummy I'd love to have the link and the chance to pick his brain.)
First off I see you bought the Kendas. Looked like a great deal on a quality tire, I hope you enjoy them and report back when you've got some miles and an opinion on them.
As for my set up, I am a tire tinkerer. I enjoy experimenting with different tire/rim combos just to see what happens. On the BigDonkey I've tried a number of things including: 2.4 Maxxis Holy Rollers, 3.7 Surly Endomorph (up front only), 3.0 Nokian Gazzaloddi, 2.1 Bontrager 'generic style mountainbike tires', 29x2.35 Schwalbe Big Apples, and my favorite set up 26x2.35 Big Apples.
All of these tires were run on a widish (~44mm) Alex DM24 rim, and a couple also spent time on a modified Sun Ringle Double wide.
If you were posing this question regarding a non-longtail setup, I would hands down recommend the Holy Rollers (which I've run in the summer on couple different bikes, including my Surly 1x1), but a cargobike is a different beast.
This spring a gypsy I crossed path with traded me some Holy Rollers he had for the Big Apples I'd been running on my Dummy. A few thousand miles later he was switching to full on fat tires and offered to mail my Big Apples back to me, to which I enthusiastically said 'yes'. I swapped the Holy Rollers off and slapped the Big Apples back on and everything was again right with the world. Not that the Holy Rollers were bad or lacking, but I just find the Big Apples to be a little nicer, a little quieter, a little smoother and a little more pleasant to ride.
The Big Apples plenty of traction for almost all of the trail riding I do on the Dummy. The long, stable cargo bike isn't getting rallied through corners quite the same way a regular bike would so cornering traction isn't a huge issue.
The flat protection from the tires is fantastic and the ride quality is super plush. I think Gypsy Nick rode something like 3,000 flat free, loaded, touring miles on my well used Big Apples before mailing them back.
A flat tire on a loaded cargobike could be particularly inconvenient.
Knock on wood, but in the past 3 years I've had no flats on the Big Donkey that I can recall.
I have however shifted the chain off the top of the cassette a couple of times and learned how annoying rear wheel repairs in the field can be.
I've had more than one instance of slamming hard into an unavoidable rock and feeling my rim make contact with the rim. Not only have I escaped without pinch flats, but I've also not had to true the rims.
It looks like the Schwalbe Fat Franks would also be a excellent option and perhaps provide a hair more traction.
Just my thoughts, no more right or wrong than anyone else's, but I'll put them out there for what they're worth.
Then I had a question I sent out to Allman and Gypsy Nick that went something like this:
6 miles through the woods to school.
4 miles on paths home.
2 hours later, in the garage, rear tire is flat . . . tear at the valve stem (presta).
2 nights in a row.
Additional information available upon request.
I have a theory or two, but would be curious if you had any additional insight.
After all the holiday thankfulness I have to say I'm thankful to be able find answers to bike questions on the internet. Not too long ago things were a lot different.
Resources and answers were quite limited by today's standards, I try not to take it for granted.
13 hours ago