Recumbent - Smaller wheels

What would happen if I put smaller wheels on my 26/26? My understanding is that it would lower the amount of trail, therefore making the bike twitchy, am I correct? I was toying with the idea of installing two 20" wheels to try it out, but I fear the change in handling might be a bit radical.

What kind of bike is it? You could actually end up with negative trail, depending on the bike.

That could be "a bad thing™"

What kind of bike is it? You could actually end up with negative trail, depending on the bike. That could be "a bad thing™"

That's true :) Although I suspect the new wheels' size would have to be really small for that to happen. But in theory it's possible.

The bike is an Optima Condor with a suspension fork. I don't think it has a lot of trail to start with, since it essentially is a mountain bike with a recumbent seat. I'll go measure the trail with 26" wheels later today.

What you will probably get is problems mounting the brakes and a much reduced gear range using a 20" drive wheel.

From what I can gather, small wheels, particularly the 20 X 20 combination that is common for compact long wheelbase recumbents makes for a pretty inefficient bike. My first recumbent was a BikeE AT. It came with a 3X7 SACHS (now SRAM) hub to make the gear range usable at the high end. It was a slug! If you are having trouble riding a recumbent with a high bottom bracket on your 26 X 26 combination, maybe it is time to move on to another recumbent as I soon did when the BikeE AT turned out to be not what I wanted in a recumbent.

What you will probably get is problems mounting the brakes and a much reduced gear range using a 20" drive wheel.

Nope, I use discs, and I could just install bigger chainrings for the gear range.



From what I can gather, small wheels, particularly the 20 X 20 combination that is common for compact long wheelbase recumbents makes for a pretty inefficient bike.

I don't think it has much to do with the wheel size, but rather with the weight distribution on those bikes. A small wheel simply has a tad more rolling resistance (although that's debatable with modern tires) and has a harsher ride, otherwise they aren't any worse than big wheels as far as road riding is concerned.



If you are having trouble riding a recumbent with a high bottom bracket on your 26 X 26 combination, maybe it is time to move on to another recumbent as I soon did when the BikeE AT turned out to be not what I wanted in a recumbent.

No no, I don't have any trouble with the Condor, and I'm happy with the bike as it is. I just wanted to try something different on the cheap.

And by the way, I still have my BikeE, it's a great little city bike :)

From what I can gather, small wheels, particularly the 20 X 20 combination that is common for compact long wheelbase recumbents makes for a pretty inefficient bike. Really? This (http://www.alexmoulton.co.uk/questions.asp) might enlighten you ;)

From what I can gather, small wheels, particularly the 20 X 20 combination that is common for compact long wheelbase recumbents makes for a pretty inefficient bike. My first recumbent was a BikeE AT. It came with a 3X7 SACHS (now SRAM) hub to make the gear range usable at the high end. It was a slug!

Bike-Es had several details that made them slow. First was their upright seating, which made the rider catch as much air as possible (and had a bad reputation for causing recumbutt.) Second was the tires. I've heard that owners who changed out to performance tires saw a noticeable speed increase. Third, from what I've heard the frame had enough flex to make it even more inefficient.

Even the best small tires have rolling resistances that would be considered very mediocre in the 700c world, but the difference is on the order of a watt or two - not enough to seriously impair a bike's speed. Unfortunately, speedy small tires are not the norm - it's much more common for small tires to be made for kid's bikes - heavy and durable vs light and fast.

Bike-Es had several details that made them slow. First was their upright seating, which made the rider catch as much air as possible (and had a bad reputation for causing recumbutt.) Second was the tires. I've heard that owners who changed out to performance tires saw a noticeable speed increase. Third, from what I've heard the frame had enough flex to make it even more inefficient.

Actually, BikeE frames have very little flex. I suspect flexy frames were found on the very first models, that had bolted-on rear arms. An all-welded BikeE is very stiff indeed.

As for tires, I ride thin high-pressure Schwalbes, or wider Hookworms depending on the season, and they indeed perform much better than the stock tires.

Bad aerodynamics can be somewhat improved by a fairing. Recumbutt unfortunately happens easily with a BikeE.



Even the best small tires have rolling resistances that would be considered very mediocre in the 700c world, but the difference is on the order of a watt or two - not enough to seriously impair a bike's speed. Unfortunately, speedy small tires are not the norm - it's much more common for small tires to be made for kid's bikes - heavy and durable vs light and fast.

I've ridden 16" tires on my Brompton that roll very well. Most notably Schwalbe Marathons, Primo Comets and Brompton's own knock-off brand which surprisingly do really quite well in the speed department, but are so slippery in the rain they should be outlawed.

With the burgeoning recumbent and folders market, the offering for small high-quality tires is getting quite large these days, and serious small tires really blur the line between small wheelers and traditional road bikes, performance-wise. They have nothing to do with child bike tires. You can even find good tires in 18" these days.