Recumbent - Wheel size and speed?

Due to neck and back problems, I will soon be buying a a bent and selling my df. I seem to be drawn to the Bacchetta Strada and Bacchettas seem to enjoy a good reputation here. I am also looking at a couple other models with a 26-20 wheel configuration as opposed to the 26-26 of the Strada. My question is .....would there be a noticible difference in speed if I went with a bike with a 20 on the front vs the 26, if all other things on the bike were equal, ie. components, frame , etc. ?? Thanks!

IMO, most of the speed capability is in the rider's legs and lungs.
Wheel diameter is compensated with the gearing of your chainrings or cassette, but the narrower the tire, seems to be more capable to go fast with less effort.
Between 26/26 and 26/20, I feel the handling difference is most noticable but not speed different. 20/26 is quicker, may feel less stable at higher speed but that just take some time to get familiar with.
20/26 usually have a more upright riding position thatn a 26/26, also closer to the ground.
Tire choice wise, you could find more choices in narrow tires in 26 size, so you might be able to get higher speed on 26/26..

One particular thing I considered when I started riding recumbent, I switch from 175mm crankarms on my DF bikes to 165mm crankarms on recumbent, since I don't get to use my bodyweight to propel the bike to forward moving, the leverage of longer crankarm is unnecessary, also since I am forced to pedal I higher cadence, smaller pedaling circle from shorter crankarms allow me to conserve more energy for the long run. I've been very happy with shorter crankarms on my recumbents.

Thanks for the reply cat0020. Your answer makes perfect sense. I have some questions specific to the Strada that I am going to post a little later but I have another general question for you about highracers. I have seen a few comments dealing foot numbness with highracers due to the high BB. Is this the general consensus or just something that happens to just a few individuals? I usually experience numbness in my hands my DF and really dont want to exchange numbness in one part of my body for numbness in another.

The hand numbness riding the DF bikes usually means that too much weight is supported by the arms, ever try bending your elbows while you ride a DF bike? that allow some weight from yourhands to your back, usually alieveate the numbness from the hands.

I suspect the foot numbness issue has to do with pushing on the pedals versus pedaling in circles with clipless or toecliped pedals. Maybe it has some to do with crankarm length, numbness occus in our bodies mainly due to the lack of circulation or outside pressure against nerve pressure points. I guess combined with high bottom bracket location and longer crankarms, a rider would be more likely to experience the foot numbness versus shorter crankarms.

Personally, I've no experience with foot numbness, I pedal in circles with clipless pedals and keep my pedaling cadence pretty healthy.
When I ride my recumbent I'm in a different mindset as riding a DF bike, I'm not so concerned about speed but just enjoying the surroundings and getting to my destination safely. Maybe eventually if I developed my 'bent legs/muscles I might be interested in a low/high racer type recumbent, but for now, I'm having fun riding my $450 Vision R40 20/26 config. that I bought on Craigslist. So far no problems keeping up with DF riders, but it would be fun to be competitive on a faster pace group ride. I need to ride more.

I'd echo what was said by Cat 0020. you will find that the leg muscles you use are a bit different and it will take a while getting used to it. I've gone to shorter cranks arms (152's) and gear down a bit and spin a bit faster than others riding the same bike, but it sure works for me. I had some post stroke/back surgery weakness in the left knee but it disappeared late last summer. Maybe due to the shorter cranks or maybe simply because I was riding more. And enjoying it better!
I lave a LWB bent and can keep up with the top middle third of DF riders easily enough (and I'm not Lance!) but I have much less, actually no, problems with aches and pains from my back, neck and no wrist pain, like so many of my DF friends experience. They are a bit slower of hills but you easily get it back on downhills and the flats.
I do ride a DF on occasions when I have no choice but only sparingly, because of the aches and pains that simply don't happen on bents.
I've never ridden a SWB high BB bent except for a mile or two, and find the laid back position a bit uncomfortable, but I'm not used to it and probably would like it once I did a hundred miles or so. The foot numbness thing I've never seen as most of the bent drivers I ride with have LWB lower BB bents and the ones on the SWB ones don't seem to experience it. Anyone out there get numb feet on low BB LWB bikes?? If so, I suspect it is much less but don't quote me on this!
The only "recumbent butt" that you hear about I've experienced when I did several days of 60 - 75 miles nonstop. At the time I wore regular shorts but learned that on long rides over 50 miles you shouldn't wear anything with a seam. I had 3 seams coming together in one spot which is normally fine, but after several days of long rides I wore a nice hole in my hide at the bottom of my sacrum! Ouch! Luckily my wife had a DF pair of shorts with padding that was a bit too large for her and I wore those for the remaining ride. Now I tell everyone that "I can sure ride great after I get into my wife's pants!"
Now I wear anything on rides up to 30 miles or so, but wear thin spandex checked carefully for no seams on longer rides.
Like cat0020 I use clipless and while I can't pedal in circles I find I can sweep my legs around towards me and extend the power stroke greatly, and I don't sorry about my feet falling off when I get distracted.

100psi tires make a world of difference too. I have Kenda Kwests (26x1.5 rear, 20x1.5 front). They're really sweet tires.

Numb feet won't happen if your pedals are equal to or lower than your seat height.

Due to neck and back problems, I will soon be buying a a bent and selling my df. I seem to be drawn to the Bacchetta Strada and Bacchettas seem to enjoy a good reputation here. I am also looking at a couple other models with a 26-20 wheel configuration as opposed to the 26-26 of the Strada. My question is .....would there be a noticible difference in speed if I went with a bike with a 20 on the front vs the 26, if all other things on the bike were equal, ie. components, frame , etc. ?? Thanks!

The 26' Strada feels faster than any LWB I've tested to date. However, the feet numbness is real and mine were starting to feel strange after a short while. You have to test the bike to find out where you stand in particular.

IMO, most of the speed capability is in the rider's legs and lungs.
Wheel diameter is compensated with the gearing of your chainrings or cassette, but the narrower the tire, seems to be more capable to go fast with less effort.
Between 26/26 and 26/20, I feel the handling difference is most noticable but not speed different. 20/26 is quicker, may feel less stable at higher speed but that just take some time to get familiar with.
20/26 usually have a more upright riding position thatn a 26/26, also closer to the ground.
Tire choice wise, you could find more choices in narrow tires in 26 size, so you might be able to get higher speed on 26/26..

One particular thing I considered when I started riding recumbent, I switch from 175mm crankarms on my DF bikes to 165mm crankarms on recumbent, since I don't get to use my bodyweight to propel the bike to forward moving, the leverage of longer crankarm is unnecessary, also since I am forced to pedal I higher cadence, smaller pedaling circle from shorter crankarms allow me to conserve more energy for the long run. I've been very happy with shorter crankarms on my recumbents.

The speed will be higher on the 26/26 than the 20/26 as the 26 has less rolling resistance than the 20.

The lower height of the 20/26 will make it easier to get on and off and start and stop.
If you're short, the 26/26 might not work well since you'd have trouble reaching the ground from your seated positio with your feet.
The 20/26 will be easier to handle at low speeds.

IMHO, speed is determined by a number of factors. The engine goes without saying. On the bike, the aero position of the rider is probably the biggest factor, followed by weight and stiffness of the frame, particularly the pedal boom.

When you push on the right pedal, the boom is reinforced against flex by the chain; but pushing on the left pedal produces no such bracing effect, so the boom tends to move to the right. Of course the frame returns at the end of the power stroke without adding anything to the bike's speed, and so the energy that went into flexing the boom is wasted. Trikes are particularly bad in this respect, because they tend to have long monotube booms. Even my Baron does it - I can move the bb almost an inch to the right by pushing hard. Bottom line: if speed matters, check the boom for deflection when you do your test rides.

Finally, yes wheel size can matter. Rolling resistance may be a large component or a small one, depending on how fast you're trying to go and how smooth your roads are. The rougher they are, the more you'll notice an advantage with larger wheels. As you go faster, rolling resistance becomes a smaller % of the total drag. On smooth roads at least, that would give some sort of weighted advantage to aerodynamics regardless of wheel size.

So the answer to your question is, "it depends." Aerodynamics, stiff frame, rolling resistance. If you have neck problems, you might have to compromise between a laid-back aero position and what your neck can handle. Or if you want speed, you might consider a fairing or tailbox instead of lying 30 degrees from horizontal.


Numb feet won't happen if your pedals are equal to or lower than your seat height.

That's not exactly true. If you read on upright bike forums, numb feet and/or hotfoot are occasionally problems for a select few of them, too. I personally think that high pedals might make an existing problem worse, but it's not the primary cause. Most often it's caused by tight shoes or some other constriction. Bents probably get a bum rap in this area because so many bent riders are FOGs (fat old guys) who are more likely to have diabetes or peripheral artery disease. Or tight pant legs, even. About the numb hands, I had those on my upright; in fact carpal-tunnel problems were the primary reason I originally got my first bent. No regrets.

I have both these bikes. There is no way the Rans tail wind will ever keep up with the tour Easy. The bigger wheels really make a difference when cruising . Crank and gear size do not make up for the difference in wheel size. Still I like them both. The difference between 26 and 28 (700) is probably not significant.
Keith -- Recumbent since 1983

I'll stick with the 20/700c nocom. Its all about aero position. The vk2 has same wheel combo. conclusion................. the nocom spanks the vk2 so bad its not even funny. otherwise I'll go with pretty much everything else blazing pedals stated. wheel rolling resistance is pretty much a silly and insignificant part of the whole picture. Its like a roadie trying to decide if it is worth shaving his legs or not.

Due to neck and back problems, I will soon be buying a a bent and selling my df. .....would there be a noticible difference in speed if I went with a bike with a 20 on the front vs the 26, if all other things on the bike were equal, ie. components, frame , etc. ?? Thanks!
From what I've heard from people who've had both, the advantage of a larger wheel is that it doesn't slow down as much as a smaller wheel does when rolling over rougher pavement.

-------

Numb feet is a complicated subject, and it's a "danger" of buying a recumbent. You usually need to do a 1-2 hour ride to see if it will be a problem, and taking test rides that long often isn't possible.

Generally speaking, recumbents with higher-set pedals DO tend to cause more problems with numb feet (poor foot circulation). I got rid of a 20/26 SWB in part because of the numb feet problem that was minor, but that I couldn't find any way to eliminate. I bought a traditional 20/26 LWB instead (with low pedals) and I haven't ever gotten ANY numb feet on it, even though I'm using the same shoes and pedals that were on the previous SWB.

Another school of though maintains that the cause of recumbent numb feet is not usually anything to do directly with your feet being elevated, but it has to do with a riding position that requires your legs to maintain a certain angle that results in compression of the arteries and veins in your hip. The only solution is still the same though--it is to get a different bike that has another leg/back angle in the riding position.
~

From what I've heard from people who've had both, the advantage of a larger wheel is that it doesn't slow down as much as a smaller wheel does when rolling over rougher pavement.

<snip>
~

The rough pavement is where the 26 has its big advantage. On the smooth surface of a velodrome, the rolling resistance advantage of a 26 over a 20 is very small.

Bearings in a 26" hub get to roll slower than in 20" (30%) or 16" (60%).

Thanks for the reply cat0020. Your answer makes perfect sense. I have some questions specific to the Strada that I am going to post a little later but I have another general question for you about highracers. I have seen a few comments dealing foot numbness with highracers due to the high BB. Is this the general consensus or just something that happens to just a few individuals? I usually experience numbness in my hands my DF and really dont want to exchange numbness in one part of my body for numbness in another.
I rode a Strada for two years. The 3 reasons I sold it are my feet would go numb over 25 miles, my neck hurt when I laid the seat back past maximum upright and in the position I rode, I got recumbent butt on long rides. I had a LWB and had no problems, other than the bike was a tank it was so heavy. I've ordered another LWB that should be in next week--I hope.

I have owned and ridden dual 650 bents and 650x20 bents and 700x20 bents and can't really tell that much difference on rough pavement. Like others have stated, to me, motor and aerodynamics means way more than tire size.

FWIW, my fastest averages have been on bents with 20" front wheels. Should I forsake them for my 650x650 bike because the wheels should or may theoretically "roll" better?