My Recumbent Tadpole Trike

My recumbent tadpole trike - ready to ride

Everyone has different needs. It is good to pimp your trike to meet them best. My configuration is for adventure on new paths without worrying about climbing hills. Speed is not an issue. I am about looking around, not getting there quickly.

Configuration Based on Needs and Budget

My first trike was a HP Veloteknic Gekko fx 20 – about 12 years old as of 2023. The original configuration was tough to ride. Now I know why. The lowest crank ring had 40 teeth. I did not understand the options then, so I installed a crank e-drive and a Nuvinci hub. Electric assist worked well for my commute but did little for my fitness. I have now given my Gekko a third lease of life to travel the rail trails and tracks.

Pedals

My recumbent tadpole trike - pedals to eliminate leg suck

My wife suffered from a “leg suck” when we first started riding. Leg suck is when your foot slips off the pedal, and you attempt to run over yourself. At best, you end up with a very bruised calf muscle. I would hate to think what “at worst” would be. I did not understand the mechanics at the time. To be safe, we started to wear clipless cycling shoes. The name is a misnomer as these shoes clip onto the pedals so your feet cannot slip off.

Clipless shoes have problems. They are expensive and often not that comfortable to walk in. The clips protrude from the sole – making walking on wooden floors a no-no. The worst problem for me is that the clip places the pedal on the ball of the foot. It maximises the stress on the angle and front of the foot while riding. The pain limited the distances I could ride comfortably.

It turns out that the leg suck issue my partner experienced was from the length of the boom. I cut it a little shorter and moved to mountain bike pedals.

I get the most oversized mountain bike pedals I can find that have good anti-skid spikes. Wear sneakers or walking shoes that allow the pins on the pedals to fit between grips on the shoe sole.

Just as importantly, use the correct boom extension. Your leg should still be bent between 5 and 10 degrees when a pedal is away from you. You won’t get leg suck if your foot cannot leave the pedal. There is another reason for this boom length. It is inefficient if your leg straightens entirely at the end of a stroke. All your stroke power occurs before your leg is straight.

Crankset

My recumbent tadpole trike - 22/32/42 crankset

The original Gekko crankset had the lowest gear ring with 40 teeth. I thought I could not keep up on the hills because of my weight. It was a bit of both.

The first thing I do now with a new trike is to replace the crankset with a mountain bike rig of 22/32/42 teeth and 152mm cranks.

The 22-tooth ring is the first step to easing riding up hills. It dropped the Gekko from 24 gear inches (GI) to 13 for hill climbing with a standard derailleur set on the rear. For me (at 85kg/13 stone), 13 gear inches means I still have to push harder for a 5-degree slope. It is possible but tiring.

The other unusual thing about these cranksets is the 152mm length cranks. Most cranks are longer than 170mm. Longer cranks work on an upright bike where you can use your weight for leverage. We don’t want our knees bending more than 90 degrees for a recumbent. Think of doing squats with your back to a wall. The further you lower yourself, the harder it is to stand back up. Most of our riding energy is over a bending range of about 70 degrees. The shorter crank works for everyone, including beanpoles. Also, it is way better for your knees.

Mobile Phone Mount

My recumbent tadpole trike - mobile phone mount

I like to watch my ride with either Ride with GPS or Strava. There are quite a few other apps. They all have their strengths and weaknesses.

Unfortunately, mobile phone holders for upright bicycles are not always suitable for a recumbent. As you can see from the photograph, I have modified (as in bent) a handlebar accessory mount to suit my purposes. The phone angles slightly downwards to minimise glare. Modern screens can be seen clearly at that angle.

Tires

I have spent most of my trike riding hours on road tires. They provide a hard ride and minimal grip on grass or dirt.

I have switched to balloon tires. The Schwalbe Big Ben tires are 2.15″ balloons. By running them at 20psi, I get good suspension below 15kph (10mph) and more surface area for off-road excursions. They also have good protection from thorns and similar nasties.

I know when it is time to pump up my tires if the trike hops when I ride over a gutter.

What they do not have is a nobbly tread. They will probably not work as well in sand or mud. I have put Kendra tires on my partner’s trike to see if the difference is worth considering.

Brakes

The Gekko has standard mechanical disc brakes on the front and a rim drag brake for the rear.

I much prefer drum brakes on the front wheels. They stop you as quickly but feel a lot more gentle. I am not sure it is even possible to switch them over. I will look for softer compounds when my pads for the disc brakes wear out.

The Gekko has a rim brake on the rear wheel and a locking control lever on the left handlebar. I have always used it as an excellent handbrake. Then I was told it was a drag brake used to slow your descent on hills. What an excellent idea. It will save me having to always hang on to the brake levers – if I ever remember to use it.

Flags and Camera Mount

Flags hang from a thin fibreglass pole – except for my trike. I like to film my rides with a 360 camera, so I have mounted a trekking pole with a camera mount using a metre of 1″ aluminium tube. I can drop it down when on the car.

I was tired of flags being lost or pinched, so I purchased a roll of orange bunting flags. They will last me a lifetime or two. They are attached with hook and loop cable ties so I can remove them while filming.

Hub Gears

My recumbent tadpole trike - Rohloff hub gears

Like almost every trike sold, the Gekko came with derailleur gears. I stuck with them until I put a crank motor on for commuting. Derailleur gearing and electric motors don’t play well together. When you stop pedalling, the e-bike system takes a second or two to drop power. You can’t change down while going uphill under load. By the time you can change down, it is often too late. We have a 250w limit on e-bikes. I imagine there would be much less need for gear changes with a 1000w motor.

I switched to a Nuvinci (now Enviolo) 360 hub “gears”. The quotes are because the Nuvinci is a continuous design without gears.

I ran with the Nuvinci for many years. It is a good and reliable system. You can change the gear ratio from 0.5 to 1.8 – a difference of 360%. It is slightly better than the original derailleur system giving me a low gear of 10 GI (gear inches) with the crankset above.

While ten gear inches is enough to ride up 5-degree slopes without stress, I cannot pedal 10-degree slopes without pain. The figures will differ for you as they depend on weight and resilience.

For my retirement chariot, I installed a Rohloff 14-speed hub. Everyone agrees that it is the Rolls Royce in bicycle gearing with renowned reliability and a gear range of 526%. My low-speed gear inches is now at 6.

A Rohloff hub is expensive – adding another half to the price of a trike if you want to climb any mountains. I hope to have a more economical solution soon.

The Nuvinci hub did not go to waste. It is now on my partner’s Catrike Villager. Installation was a doddle as I kept it on my Gekko rim. She weighs 50kg (< 8 stone). I think 10 gear inches will work for all the hills we ride. Time will tell (as will William).

Exclusions

Well, one exclusion, anyway. Adding an electric motor in the hub or crank has become very popular. I had one for when I was commuting. Now I am riding for exercise and pleasure. Electrification takes that away for me. I also want to travel and try out distant rail trails. Electricity needs charging points. An e-bike system also adds complexity and increases the chance of failure.

A modern mid-drive (crank drive) with a torque sensor allows exercise, but you will need the power to replace the lower gearing you lose when installing the drive. It comes with a 42-tooth chainring – compared to the 22 tooth smallest chainring on my crankset.

A hub electric motor allows you to keep all derailleur gearing but precludes hub gears such as Nuvinci or Rohloff. There is another option. A Schlumpf Mountain Drive replaces the crankset. It has two gears – 1:1 and 2.5:1. One version comes with 27 and 38 tooth chainrings. At low range, this gives the same as an 11-tooth chainring giving six gear inches using the standard derailleur at the rear. There is no turning back once installing a Schlump system since the installer has to bore out the bottom bracket.

Imperfections

For every problem, there is a solution. Every solution creates another problem.

  1. The disc brakes feel scratchy and a bit abrupt. I will be interested to try softer pads.
  2. The brake handles are too short. Putting the gear change below the grip means the brake handles mount lower. Longer brake handles stick out further from the handlebar, making them harder to use. I minimise discomfort by adjusting the brakes to activate when the brake handles are close to the handlebar.

That’s about it – for now.

In Conclusion

I am happy with my setup. The perfect recumbent tadpole trike will vary from person to person and from use to use. Please let me know what your preferred setup is.

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