Background:
I recently bought a Bike Friday Pocket Rocket Pro with 451 wheels (& Panaracer Minits 28-451 tires). After riding it enough so that I was over the “talking myself into it” phase and getting the feel of the bike it’s clear that the handling is much more “nervous” and “twitchy” than what I want & need in a bike. Understand that i’m not claiming that there’s anything wrong with the bike - only that on the bike handling spectrum from criterium bikes on one end to downhill MTB’s with 65mm of trail on the other end the Pocket Rocket is all the way on the left end of the spectrum. Sure it’s rideable - if you’re experienced and have good reflexes. Unfortunately i’m older than dirt and have some neurological issues that mean I need a super stable bike that any fool can ride no handed.

When it became clear to me that the PRP wasn’t going to work for me as it was set up I measured the trail of the bike and came up with approximately 35mm - which is about 20 mm less that the normal range for full sized road bikes. I wrote to Bike Friday and asked them (a) what the geometry figures were for my bike and (b) why they used so little trail and (c) did they have any practical suggestions as to how I could modify the bike to get the stability I need. I exchanged several emails with people in a position to answer questions like these and their answer to (c) was “no” and their answer to (a) & (b) was resounding silence. In other words they don’t want to talk about the geometry of their bikes - period. In fact they have, so far, refused to even disclose what the geometry figures are for my bike. (This is a side issue but my entire experience of buying the PRP leaves me with the strong impression of a poorly run business that can’t even spell “Customer Service”)

After that dead end I did a lot of searching online about bike geometry and found a lot of good info but it was virtually all on full sized bikes with big wheels. So this (finally!) brings me to my Questions:

Is there any inherent reason why a bike with 20” wheels can’t ride as “stably” as one with 700 / 650 / 26” wheels?

What is a “normal” trial figure for other bikes with 20” wheels?

Do any of you have bikes with 20” wheels that ride as stably as a “full sized” bike?