A number of Catrikers on the Forum are probably familiar with the Utah Trikes Catrike extension kit that permits 20” (406 and 451) rear wheels to be replaced with 26” (559), 650c, or 700c wheels. Don’t know how many have ordered and installed the kit, so I thought I would post my experiences with it. I ordered a kit for my 2007 “Speed” to turn it into a quasi “700” (Installed a 26” wheel, instead of a 700c). Cost a total of $184, which included $9 for shipping. Thankfully, I didn’t need a chain rerouting kit, which ranges in cost from $100 to $145. I already had a spare 26” wheel, tire, and shifting cable, so the conversion cost was minimal. Installation of the kit took about an hour. Installing a shifting cable, adjusting the chain length, making other adjustments, test riding, and changing out the cassette, after the test ride, took several more hours. The CNC machined aluminum extensions fit like a glove over the original dropouts. I didn’t experience any installation problems. The extensions for 2007, and earlier, trikes require additional machining that must be requested when the order is placed. Otherwise, they won’t fit. Rode the trike a couple of miles, yesterday, and 38 miles, today. Not enough miles to fully evaluate the effects of the kit on the trike, but here are a few observations: (1) Spun out at 28 mph (108 cadence) in the middle chain ring, yesterday. Before, I would spin out at 28 mph in the big ring (With stock 451 rear wheel); (2) The ride seems smoother with the 3-1/2” increase in wheelbase and 26” wheel/tire combination; (3) As would be expected, acceleration is decreased with the increased wheel diameter and heavier wheel/tire combination; (4) Does the trike roll faster with the bigger wheel? Don’t know. Need more riding time; (5) Handling of the altered trike seems fine. The turning radius is of course slightly longer; (6) The seat angle was not affected. Photos follow:  
 

Trike with stock 451 rear wheel
 

Extension kit
 

Trike ready to receive extension kit
 

Extensions and derailleur installed
 

Trike with 26" Aerospoke wheel

Quote from rmillay on May 5^th, 2011, 7:01pm:

 
A real pro has more than one jackstand. I have a bunch of them behind the garage (Approx. 30 bricks).  

very nice looking ride there Jay...

Jay that looks really good. You might temp me into trying that with my Road some day.

Jay, if it's like mine, the seat frame clamps can be rotated to get it out of the way.  I had to do that for clearance for the bigger tire.  You have to readjust the headrest then, of course--a pain in the neck.    

Did some coasting tests on the steep portion of the path that parallels the WRL dam spillway to see if the the trike rolls faster with the 26" rear wheel than with the stock 451 wheel (Both wheels had Schwalbe Stelvio tires mounted and pressured to 115 psi). Looks like the trike achieves a slightly higher terminal velocity with the larger rear wheel. Removed the Aerospoke wheel and installed a 26" wheel with 24 wire spokes. The Aerospoke wheel is stiff, and the trike really bounces around at speed on the wooden bridge planks at WRL with it installed. The bouncing could probably be reduced by installing a wider and lower pressure tire, but I like narrow, high-pressure tires.

Quote from power_bent on May 11^th, 2011, 7:26pm:

 
115 psi, Tom.

But unless you ride terrain that's perfectly smooth, most of your weight can end up on one tire for an instant, and that's all it takes for a pinch flat.