Delta trike vs Tadpole trike

[Night Train]

Throughout all my thoughts on recumbents and HPVs I have only really considered tadpole trikes (two wheels at the front) and ignored delta trikes (two wheels at the back) altogether.

My reasoning so far has been that with a tadpole there is a lot of weight on the front wheels which provide the grip for both steering and braking. The rear drive wheel will always have all of the tractive effort available from its share of the weight. In motoring tadpole layouts are more stable in cornering.

Delta trikes have less weight on the front wheel so it can't give its best in both breaking and steering. In motoring delta trikes are more unstable. The rear drive wheels have one of the following:
One drive wheel - causes the trike to pull to one side
Two drive wheels on freewheels - when cornering all the drive goes to the inner wheel countering the turn
Two drive wheels with a differential - allows the wheel with the least grip to spin away all the drive effort on loose or slippery surfaces and then cornering (unless someone knows of a limited slip diff version)

So those have been my thoughts about the two systems based on nothing more then my original, and possibly flawed, assumptions.
What I feel I need is some balance, to know what is so good about delta trikes over tadpole trikes and just how flawed my assumptions may have been in the first place.

Over to you lot.

Thanks,
NT

 

[ufkacbln]

I have not ridden a delta trike for many years - I tried a "Sinner" in the early '90s.

However I have experience of both short and long wheelbase bikes.

One of the considerations is traffic - I find that a LWB is more difficult to manage at corners, where visibility can be a problem.... it is difficult to get far enough forward to see without the front wheel protruding beyond the junction. However this can be compensated for by the additional height of LWB.


It is not unmanageable and as I said personal.

As always the only way that you are going to find out is to try them out and see how you get on.

 

[byegad]

I have a QNT and a Kettwiesel. I've answered this question a number of times. The latest is at:-
http://www.bentrideronline.com/messageboard/showthread.php?t=46598
Also see:-
http://www.bentrideronline.com/messageboard/showthread.php?t=46598
Hope this starts to answer your question.

 

[Auntie Helen]

Byegad, the two links you've posted are the same!

 

[Night Train]

Cheers Bygad, that's informative.

Whenever I have been in a position to ride a trike I always go for the tadpole and so have never riden a delta of any description. Must change that I guess.

 

[ufkacbln]

Of course - you may have to buy both!

I am impressed by the new RANS Trizard - looks very impressive

 

[Night Train]

Of course - you may have to buy both!

I am impressed by the new RANS Trizard - looks very impressive

I can't afford both. I will work out what I actually want one for and see if either fits my needs.

The Trizard is impressive looking. It looks like it should have a limited slip diff and a sleek velomobile fairing.

 

[Riding in Circles]

Derailleur looks very vulnerable, I think the only advantages that a delta sometimes has is a higher seat height and easier storage options, both of which are addressed with the new Catrike Villager which has a high seat and will be able to stand up on its back with our new custom rack.

 

[ufkacbln]

I didn't say it was "Practical" - just impressive.... After the CAtrike and previous Trice I would not go back to LWB.

One of the reasons I chose the Catrike Expedition was dérailleur clearance - I know smaller wheeled bikes are quite capable and safe as the dérailleur is close to the wheel, whereas the one on the Trizard is open to speed bumps, road debris etc, but it was just a personal feeling.

 

[Night Train]

So far deltas seem to be long wheel base and tadpoles shortwheel base.
Are there short wheel base deltas and long wheel base tadpoles?

 

[ufkacbln]

So far deltas seem to be long wheel base and tadpoles shortwheel base.
Are there short wheel base deltas and long wheel base tadpoles?

....ish

There are a number of medium wheelbase Deltas such as the EZ3 and "Roadster"

However the need for the distance between chainset and seat has a certain minimum.

As for LWB tadpoles - again there is little to be gained for a solo, but the design lives well as a tandem

 

[Night Train]

....ish

There are a number of medium wheelbase Deltas such as the EZ3 and "Roadster"

However the need for the distance between chainset and seat has a certain minimum.

So there aren't any with the front wheel behind the chainset then. Perhaps that would be unstable.
No tadpoles with front wheels ahead of the chainset either then.

 

[ufkacbln]

I stand to be corrected, but not that I am aware of....

There are a couple of "oddities such as the (Human Power Machines ) Trihauler or the (Organic Engines) "SUV" but these are "worbikes" rather than the type of machine we are discussing

The only "commercial leisure trike that fits this format is the ZOX T20, but this is frintwheel drive - another kettle of fish...

 

[Night Train]

The steering on that looks more interesting. Articulated steering to prevent chain twist and leading drivewheel for steering stability. The angle of the articulation needs to be right to allow it to self centre with its own weight but without making the steering too heavy.

The only "commercial leisure trike that fits this format is the ZOX T20, but this is frintwheel drive - another kettle of fish...

Looks odd to be honest. It would probably lose steering angle with the twist in the chain

 

[squeaker]

Delta plus

Derailleur looks very vulnerable, I think the only advantages that a delta sometimes has is a higher seat height and easier storage options

And a tight turning circle,
.
.
.
.
and being able to be parked vertically (Kettwiesel)

Damn, that pics got me thinking about lowracers again (that's a Baron lurking by the bench) :~