On Thu, 25 Sep 2014 15:27:31 -0700 (PDT), JS
wrote:

Just finished this conversion.
Found a flat-free wheel and tire at the local Tractor Supply Co (tractorsupply dot com).
SKU 3553230 "Never Flat Tire, 8 inch". It's rated for 220lb / 100kg and has a 2.50x4 tire.
It's soft enough to provide some shock absorption.
....
detailed text deleted

Here is another approach to this problem. I posted a brief summary on
r.a.s. 3 years ago, but here is a somewhat more detailed note I put
together for a fellow club member 2 years ago.

===================
Several years ago I got tired of continually having to pump up the
pneumatic tail dolly wheel for my Ventus. I ended up replacing the
inner tube with a solid rubber inner tube replacement sold under
the name "No-Mor Flats". I got my tubes from Cyclo Manufacturing in
Denver, CO. While they no longer appear to be in business, a
quick google check shows a number of alternate sources for the No-Mor
Flats tubes. E.g.,
http://www.amazon.com/Bell-No-Mor-Fl.../dp/B001UGAJYA., or
http://www.noflattires.net/cart.php?...ategory_id=117

http://www.toolboxsupply.com/product...x?sku=10698202

Looks like Bell may have bought out the manufacturer.

I used a 20" x 2" version that No-Mor Flats termed a "20B7". This
tube is for a larger 20" wheel so I had to measure the circumference
of my tail dolly wheel and cut the continuous No-Mor Flats solid tube
to a shorter length to fit inside the tire. It took a little trial and
error (cut oversize first) but a couple of iterations got it
right. I just butted the ends together inside the tire. While these
are obviously intended to be used in a continuous configuration, I
have not noticed any problem with the joint in the dolly tail wheel.
It might be worse in a tail wheel with higher speeds, but I figure
it's worth a try versus the hour or so it takes to drop the tail
wheel, reair, and reinsert with it's 4 shims that seem take a dozen
tries to get in place.

More details, cost is around $23. The actual diameter of this
tube is 1.625" (41.3mm), and the weight of a 39 inch length is 1.5 lbs
(99 cm, 0.68 kg).

No problems in over 4 years with the tail dolly, no flat spots.
Maybe a little heaver than a pneumatic tube, but well worth the
avoidance of flat tires and continual repumping.

After several years of success with the tail dolly, I followed the
same procedure on the pneumatic tail wheel of my Ventus cT

No problems once installed, though the 20" x 2" model I used (20B7)
was about the same size as the fully inflated pneumatic tube, which
made installation of the wheel shims a challenge in the confined space
of the tail wheel well.

The actual rubber tube from No-Mor Flats varied between 1.65" and
1.75" in diameter.

Side note, the added weight was less than 0.5 lbs (1.735 lbs to 2.220
lbs), resulting in negligible CG shift in my configuration.

Bob