Tuesday, April 2, 2013

Less caster angle?

I spent an afternoon at LTE recumbent bike shop. The owner Boudewijn, from the Tripod and Tracer trikes, suggested I did less caster on the Tribolt. The tilting effect will be less as a result.

Maybe he is right. Maybe not. Point is he always links the front brakes on his trikes. Then you don't need centerpoint steering.

When I built the first copy of the Raptor I had no steering axis inclination. The handling was perfect. With 14 degrees caster. After I added my design steering the brake-steer was as god as gone, or at least very manageable. But it didn't improve anything else.

So I will do some experiments with less caster and less kingpin angle and compensate with the wheel axle further behind the kingpin.

The last word is not spoken yet about the steering. It's complicated. My L-profile setup works fine. But perhaps it can be improved by other angles, more or less Ackermann compensation and axle placement.

If you do link the front brakes, please consider the simple straight Raptor method with no steering axis inclination whatsoever. Death easy construction. I found 14 degrees working great. Less then 10 degrees and you may encounter problems with the bottom bracket height and your heels touching the road. Check before you drill.



  1. Study of the tribolt's, Kingpin to Wheel Axle Orientation...

    i understand that the axle of the wheel should be trailing (behind) the king pin orientation... but in the case of the tribolt, were the wheel axle centerpoint is in a higher point to the ground, over the ging pin.. How does this rule apply?

    could moving the trail distance 1 cm back changing the axis angles towards the desired tire contact patch area, will affect positevelly the center brake steering??

    Perhaps a bit of negative camber and a bit of a ‘Toe-In’ relationship is desired to provides greater straight line stability and better braking at the cost of efficiency on cornering response.


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