# Delta trike vs Tadpole trike



## Night Train (13 Feb 2009)

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


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## ufkacbln (13 Feb 2009)

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.


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## byegad (13 Feb 2009)

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.


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## Auntie Helen (13 Feb 2009)

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


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## Night Train (13 Feb 2009)

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.


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## ufkacbln (13 Feb 2009)

Of course - you may have to buy both!

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


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## Night Train (15 Feb 2009)

Cunobelin said:


> 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.


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## Riding in Circles (15 Feb 2009)

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.


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## ufkacbln (15 Feb 2009)

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.


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## Night Train (15 Feb 2009)

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


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## ufkacbln (15 Feb 2009)

Night Train said:


> 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


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## Night Train (15 Feb 2009)

Cunobelin said:


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


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.


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## ufkacbln (15 Feb 2009)

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...


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## Night Train (15 Feb 2009)

Cunobelin said:


>


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.



Cunobelin said:


> 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


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## squeaker (15 Feb 2009)

*Delta plus*



Catrike UK said:


> 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) :~


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## byegad (16 Feb 2009)

I own a QNT and a Kettwiesel. The overall length of the Kett' is about 4" longer than the QNT. Both lengths are height of rider related so taller riders will find the same difference as me in the two models.

I'm more secure on the QNT in corners, in that I can, and every so often do, lift the inside wheel in a corner. The Kettwiesel is pretty good on corners too, I have never lifted a wheel, I do take it a little bit steadier than on the QNT. I feel if it lifted the inside wheel on the Kettwiesel it would be harder to control than the QNT which is a totally instinctive correction for me. This is purely a confidence thing, I do not have good balance so others may well feel differently. Hase have some video clips of their riders on two wheels so it is certainly possible.

The Drum brakes on the QNT give much better braking than the Avid BB5s on the Kettwiesel. This is because the QNT has effectively two front brakes and the Kettwiesel two rear. It's not that the Kettwiesel brakes poorly, it stops in around the same distance as a DF, maybe a little better. The QNT brakes almost as well as my car!

I find the Kettwiesel is slower by 5 to 10% than the QNT over routes I regularly ride. Part of this is the slightly lower top gear on the Kett' which limits my habit of swooping down one hill to 'charge' the next up hill stretch. Other factors to take into acount are the more upright riding position on the Kett and the general difference in overall height. The QNT seems to 'feel' headwinds less, being so close to the road.

The Kettwiesel is a drier ride on wet days, I use the same Streamer Fairing on both trikes and the mount is relatively higher on the Kettwiesel allowing more side access to water from wind blow rain and vehicle spray but the front wheel has a mudguard and mud flap so doesn't wet me even when hitting a deep puddle. The QNT front wheels send spray sideways onto my lower thighs. Also the QNT seems to be at such a height that spray from passing vehicles hits my face more than on the Kettwiesel where I'm some 10" higher. 

Parking in town favours the Kettwiesel as it can stand on its tail, so avoiding young boys 'trying out' the seat as they have been known to do with the QNT! 

Riding in traffic is easier on the Kettwiesel as its height gives better vision and visibility. I use a flag on the QNT and not on the Kett' to enable drivers to 'see' me. 

Both trikes are now on Big Apples and the rear suspension on the QNT really takes the sting out of bumps, the difference is noticable.

To sum up.
1. The Kettwiesel is better in the wet.
2. The QNT is a little faster.
3. In a busy town the height of the Kett' alongside its tighter turning circle makes it the first choice.
4. Off road or on bad road surfaces the QNT is a more comfortable ride.


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## Night Train (16 Feb 2009)

That is a really good write up there Byegad. Thank you.
It gives a really good impression of when and why one would chose one layout over another.


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## byegad (17 Feb 2009)

Thanks Night Train,

Having two trikes was the second best thing I've done in cycling. The best was to buy my first trike!

I would add that if ever forced to sell a trike I'd reluctantly let the Kettwiesel go. That's because I live in a small village and so ride in open countryside more often than in town. If I lived in town the QNT would be the one to go. Hopefully I'll never have to make that choice!


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## kbrumann (24 Sep 2009)

Cunobelin said:


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




Is there anyone in East Anglia with a Zoxbike or Zox Tandem willing to show it or let me test ride one? 

I am very keen on a allwheel drive, seperatable tandem like this one:



but would really want to find out more about front wheel drive in practise...

K


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## Chonker (25 Sep 2009)

I have not ridden a delta trike, however the tadpole layout makes more sense to me mainly due to the greater tyre contact on the steering/braking wheels. 

It also allows the arc of the legs to pass between the wheels rather than having the wheel between your legs (limiting steering angle) or having an overly long trike (see Rans Trizard, very cool, but BIG) and the turning circle to match. Keeping a low CoG and small frontal area, it also fits the ideal aerodynamic teardrop shape for fairings without large overhangs.

With a delta trike wouldn't you need driveshafts/differential (probably bespoke parts) at the back? Sounds expensive and heavy (though ackerman steering isn't so light I guess)


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## byegad (25 Sep 2009)

Most deltas turn much tighter than a tadpole, my QNT is 4" shorter than my Kett' yet the Kettwiesel turns in little more than its own length. 

The Trizard is plain huge, so may have a turning circle similar to a tadpole. 

Brakes on trikes are typically on the pair of wheels. 

My Kettwiesel, now with Avid BB7 calipers, stops as well as any bike, locking one or both rear wheel is possible but as the front wheel is so lightly loaded, carrying in my case just over 20% of the weight, braking the front wheel would add little to deceleration. 

My QNT, using SA drum brakes, will on a dry road lift the rear wheel under extreme braking (Not something you want to do as the trike then tries to swap ends on you!) and will out brake any DF bike by a good margin. I'd go so far as to say that the QNT braking is comparable to my car. Adding a rear brake makes sense if you are going to use it as a parking brake, or as a drag brake, but in an emergency stop all it will do is make swapping ends easier as the then lightly loaded rear wheel locks up. KMX have entertained a generation of kids by fitting a rear brake so the kids can do this on purpose. Ask any of their parents about the cost of repacelent tyres for the KMX


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## Chonker (25 Sep 2009)

During braking your front wheel wont be carrying just 20% weight though


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## byegad (25 Sep 2009)

Chonker said:


> During braking your front wheel wont be carrying just 20% weight though



I'd accept that but 20% initially means it would be very likely to lock up at the point of application. 

My point is that with effectively two rear brakes the Kettwiesel pulls up at least as well as my Thorn Club Tour did, and with less chance coming to grief while overdoing it.


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## ASTROPY CAPTAIN (6 Mar 2014)

Hey!! Frnds want some suggestions from aal of you. As i had read your reviews about tadpole and delta, i found it so much help full. Idon't know rather you all know about SAE(Society of Automotive Engineers) ornot. But, I am going to make a Hybrid tricycle using BLDC motor. Which will be of two sittings. then in that case i would like Your suggestions that I should use delta system Or tadpole. Ita a big confusion for me. So, guys plzz help me to solve out this problem.


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