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Funk49
06-27-2018, 11:51 AM
New user from Carlisle Pa, just starting on my first bike build but have a long history of building various junk. I actually do have a relevant question.

I want to build a 3 wheel recumbent and saw a thread about flipping a delta trike when riding. I'm not overly concerned about flipping when it is mishandled but I'm curious about the relative stability of the various trikes on the site. Where it matters is in an emergency such as avoiding a car.

The major factor is the center of gravity and the width of the wheel base. Is there a difference in the stability between a delta and a tadpole with similar characteristics? Also, which of the designs are the most and least stable of the bunch?

darnthedog
06-27-2018, 12:14 PM
Center of Gravity is the key to avoiding this issue. If built to the plans I believe most of the Trike plans on this site are stable. They become unstable when they get modified without taking COG into account.
There are various discussions on COG. But one key factor is keeping the primary weight at or below the axles. Length and width can also become part of problem when trying to shorten or narrow the trike regardless of Delta or Tadpole. Lastly is speed. Excessive speed can make even a well balanced trike tilt. But for the most part "if" you follow Brad's instructions on the plans it will be a safe ride. Otherwise experiment at your own risk. But we love to help new folks out. So it you want to try something and unsure ask. It may have been tried before, an of course there is always an opinion hanging somewhere.
But best to not worry about that so much as to have fun building. Photos help a lot. So be sure to post photos as you can. And welcome to the fun.

DannyC
06-27-2018, 12:34 PM
There is a very good primer on all trike designs and their pro's & con's.
https://pdfs.semanticscholar.org/5ee5/84368629fdc7ad69a3adf63da2c8e90de9f4.pdf

Twinkle
06-27-2018, 01:24 PM
Welcome from the UK

enjoy yourself - My preference is the tadpole with USS and Disc brakes with a low seat for performance and stability.

regards emma

stormbird
06-28-2018, 10:04 AM
This is also an interesting read ?

https://web.archive.org/web/20171221030453/http://www.jetrike.com:80/tadpole-or-delta.html

However there are some glaring errors in both of them ?

Dans assumes the brakes for a Delta will be on the front wheel - all commercial Deltas I know of have brakes on the rear.

Both try to compare a tadpole with a low seat height with a Delta with a higher seat ? this does not have to be the case for instance my python has a 8" seat height comparable with most tadpoles and lower than some commercial models ....

Big thing is to decided what type of riding you plan to do and which configuration gives you the mosts pluses ?

Funk49
06-29-2018, 11:02 AM
Thanks, it looks like that is a serious read. Mostly I was curious after reading a thread about wheels being lifted how the different designs compared especially in the case of ***, I'm going to run into a brick wall scenario. In general, I expect the designs as is are rather stable but it isn't obvious looking at the pictures which have the lower COG and such.

darnthedog
06-29-2018, 04:08 PM
"Eek I'm going to hit a wall"
Sorry there is not a bicycle out there that is going to be safe in that scenario. Not many vehicles will be. Maybe a tank or a bulldozer.

Now as to what to build. My suggestion is pick six plans- Read through them and choose. I like the Warrior, Timberwolf, Deltarunner. Emma favors the Streetfox modified for her.

And most of the plans can be modified to use what you like. For example, Underseat steering is Emma's go to. Then there is drum brakes or disc brakes if you like. Any number to biking transmissions. Most depending on your pocket book or ability to fabricate your own. An example of an expensive transmission. Nuvinci N360/380. Its a CVT no external gearing to change. There other options as well.
Then there is the recent expansion of fat tire bikes and wheels. That can run you a pretty penny as well. But you build to your budget. Not the latest craze.
You can build with nothing but scrap bikes even. But it is up to you. Don't like what you built, then try again.

bkentr
06-29-2018, 09:20 PM
Eek ! I've not hit a brick wall, but I have hit the pavement face first. I don't recommend it.

I do go for using recycled bikes and other parts to build projects. Keeps the cost really low. Also will provide plenty of test rides to
find out if one build is worth building a first class bike with new parts.

An example is using V-brakes, with the added support, rather than drum or disk, because the parts can be found on used bikes.

So far I have had more fun building, experimenting, and playing around with bikes than riding them.

The latest build is a Short wheelbase Recumbent Tandem Delta Trike. A combination of several plans, and my own additions.

DannyC
06-30-2018, 01:34 PM
Whatever you decide on..... we all like pictures and regular build reports. :)