View Full Version : Bottom Bracket instead of headset

08-22-2013, 02:58 PM
Hi to those that might know.
Just bouncing ideas about.

I was wondering if anyone had tried or considered using the bottom bracket for the steering system on a tadpole trike instead of the headset setup?

The reason i ask is that i got 4 shimano UN-55 square tapered BB's off a friend, brand new unused and thought they may be used in place of the headset set up.

So what do you think, anyone had this idea before?

09-28-2013, 10:54 AM
Id think it would work, but you still would need the tube to put it in. Im just starting my build, so im just chiming in with my thoughts. Other than having them why not just use a head tube?

09-28-2013, 12:43 PM
Hi all

Probably not a good idea.
a) pedals are attached at right angles to the bearings so the forces are acting at right angles
b) headsets have the forces in line with the bearings
c) considerably heavier

How are you going to attach the wheel axles to the square stub the pedal fits onto ?


09-29-2013, 04:52 AM
Nothing is impossible, but I am not too sure this is practical.
How will will you attach then wheels--welding is not a good idea non heat treated steel unless you known what has been done to the axle, and you know what you are doing when welding!
The head set is the best answer, but if you cab attach the wheels OK--the BB isn strong enough for the job.
Steve G

Radical Brad
09-29-2013, 09:34 AM
I did this with a 1 piece BB once...


Since you will be welding to the axle, you have to ensure that it is not hardened. A 3 piece BB axle will be very hard steel so you will need to find an old steel crank arm and make a removable axle adapter instead of welding to the axle.


10-02-2013, 04:54 PM
It seams great minds think alike Brad, thanks for the input from everyone, i think they will work very well not counting making an axle piece that bolts on the bottom and similar as control arms on the top, the square taper fitment is designed to take vast amounts of torque, far more than created by steering forces etc on a trike but alas they will be much heavier. I thought about this idea for a tandem i will build during the winter.

On a different but equally awesome note, my wheels just arrived from TerraTrike, great price they were, tires and tubes tomorrow then i can build my axles, its all coming together now :)