Glen’s Delta Trike

Glen Aldridge, regular reader and commentator of Trike Asylum, and also a member of the 2011 Coast to Cactus Tricycle Expedition, is a man of diverse interests and directions. While a tried and true tadpole triker, Glen has also been curious about the world of delta trikes, those bizarre vehicles with two wheels in the rear and one in the front.

Well, if you know Glen, you know that he is not usually content with the status quo, likely a reason he and I get along well, so, rather than purchasing a delta to experience these backwards trikes, he went and built his own! Yep, and today, you will read some of his initial thoughts because it is now rideable, and also see a few photos he sent. Following the pics is Glen’s letter, and following Glen’s letter are Esko’s thoughts.

By the way, this avid triker also is seriously contemplating the acquisition of a new HP Velotechnik tadpole trike. This delta is simply a curious diversion from triking as usual.

Hi Steve,

This trike has been a long time coming and except for a few needed bits of fine tuning & breaking in seems to be working quite well. Still needed are the front derailleur which is coming from Flevobikes in Holland, Mirrors & lights.

I have noticed a couple of strange tendencies & maybe the engineers out there may know the cure.

When standing still the front wheel will flop to one side & as soon as you sit down, the weight pivots the wheel straight ahead. – (Not such a bad thing)

When pedaling the slightest shift of your weight on the seat will want to change steering direction – (Quite a bad thing)

When cornering most bikes or trikes require you to lean to the inside of the turn to counter centrifical force. On this trike in order to turn sharply you have to lean to the OUTSIDE of the turn which causes you to turn tighter to the inside. (sharper turn) (Very bad thing)

Absolutely no brake steer at all – NONE!. I can brake with one hand on either side or both on a hill or on a turn and there is not the slightest pull to the side. (I haven’t tried this at 50kms/hr. yet) (Very Good Thing)

My wheels & axles must have had very good bearings as it takes very little effort for this Trike to coast quite a long way. This is using a Nexus IGH 7 speed which I think has higher drag than most cassette hubs. (Very Good thing)

This build was based on Mr. Esko Meriluoto’s Hipparrion which he designed & built several years ago & has cycled many 1000’s of Kilometers through Finland & other Scandinavian countries. The tendencies described on my build may be due to my error & not inherent weaknesses of the Hipparrion design.

What I would like to improve – Lighter weight. I have already figured out ways to shave about 4kgs. off the frame & reduce the amount of welding required. Current frame weight is about 10kgs. Total Trike weight is about 18kgs

Brakes – Although the brakes function quite well they require considerable pressure on the levers. This may improve as the brake assemblies wear in but in case of Panic Stops I would prefer an instant response on the levers which may require disc brakes or possibly Sturmey Archer drum brakes.

Handling – straight line performance seems very stable as long as you don’t shift your buttocks on the seat which of course is not practical, also cornering. Why the need to shift weight to the outside of a turn in order to turn tighter circles?

Anyway next build will be more polished & have these quirky things sorted out.

Glen

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HERE ARE ESKO’S THOUGHTS ABOUT GLEN’S COMMENTS:

Hi Glen and others!

Great to read real test results! After 17 years and about 90.000 km pedalling Hipparion (versions 0…2) I hear the first real comments about driving Hipparion. I send this message to all of you because I think, there is some interest – at last. When standing still the front wheel will flop to one side & as soon as you sit down, the weight pivots the wheel straight ahead. – (Not such a bad thing)

This is one of the most important ideas. It differs of Flevo Trike, I thought the steering mecanism again and changed it. I think it’s now good. I have a steering damper on front wheel, maily to keep the front wheel straight when parked. Earlier I thought that it’s necessary for safety to avoid hazardos steering movements. Sitting on the trike centralizes the steering front wheel. The higher is the driver’s weight, the stronger is the centralizing force.

When pedaling the slightest shift of your weight on the seat will want to change steering direction – (Quite a bad thing) Better to keep the button still. Leg steering. When cornering most bikes or trikes require you to lean to the inside of the turn to counter centrifical force. On this trike in order to turn sharply you have to lean to the OUTSIDE of the turn which causes you to turn tighter to the inside. (sharper turn) (Very bad thing) No! Don’t do that! I have tested. Tilt your shoulders to inside. Slight turns do not need any movements.

You seem to have brakes only in rear wheels. I have two brakes in front wheel and no brakes in rear wheels. Front brakes are much more effective and also safer. On slippery conditions the rear end will slip sidewards if you brake with rear brakes.

I have Shimano Roll Brake and Magura rim brake in the front wheel. After 41.000 km driving (Hipparion Protohippus 2) the front rim broke and I had to order a new front wheel (with Shimano 8 Intern). Magura brake was not possible to install with the new broader 20″ BMX-rim (the only I could get), so I had to install a traditional mecanical rim brake. But it works.

One guy in Finland made a wooden Hipparion and said it to be dangerous cecause of wobling. The geometry was just right but the material was too flexy. My Aluminum frame does not flex and is safe above 50 km/h speeds (maximun tested 57 km/h).

*What I would like to improve -* Lighter weight. I have already figured out ways to shave about 4kgs. off the frame & reduce the amount of welding required. Current frame weight is about 10kgs. Total Trike weight is about 18kgs

Great! My Hipparion weights about 22…23 kg kg. I have used thick (10 mm) Aluminum parts in some places. But it is a prototype, now 12 years old. It could be lighter – allso using square tubes.

Anyway next build will be more polished & have these quirky thing sorted out Glen. Good luck! I am very interested! Sorry about my English! I learned it 50 years ago when Swedish and German were the main foreign laguages at school.

Cheers! Esko

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One of Glen’s previous tadpole trikes, the Trident