adding trail to a tailwind

Hiya

I'm sorry if this has shown up for the 4th time. tech problems.


Any suggestions on how much trail I should get added to my
tailwind? The
high speed stability is fine but anything below 7kph / 4mph and the
bike is
a handful. I was thinkin about 4 inches. The trail is currently in the
1
inch or less range. I have a feeling that the brakepads and rim wall
may not
line up if the fork is straightened too much.

wrote:
Hiya

I'm sorry if this has shown up for the 4th time. tech problems.


Any suggestions on how much trail I should get added to my
tailwind? The
high speed stability is fine but anything below 7kph / 4mph and the
bike is
a handful. I was thinkin about 4 inches. The trail is currently in the
1
inch or less range. I have a feeling that the brakepads and rim wall
may not
line up if the fork is straightened too much.

I think that adding trail will make your low speed problems worse.

--
Order Lords of the Chainring
http://www.calpoly.edu/~wpatters/lords.html

Or use pay pal


Reply to

I'm with you. Adding trail aids high speed stability to the detriment
of low speed stability. If you want low speed stability, lose some
trail at the possible cost of making steering twitchy at higher
speeds.

I have a tailwind and plugged Patterson's equations into Mathcad. His
equations verify exactly what you say below. For example, reducing the fork
offset 10% from the measured value to increase trail caused Patterson's
sensitivity measure to increase by a whopping 67%. The fork flop nearly
doubled. This is not the direction you want to go. Increasing the trail on
the Tailwind will make it unridable at low speed. The design is already on
the edge at low speed and I have the scars to prove it.


"hfhfh" wrote in message
...
I'm with you. Adding trail aids high speed stability to the detriment
of low speed stability. If you want low speed stability, lose some
trail at the possible cost of making steering twitchy at higher
speeds.

thanks guys

I changed my handlebars to a wider set yesterday and noticed an increased
stability at low speeds today. What also seemed to help is having just one
hand on the bars at a time. Weird

"Samuel Burkeen" wrote in message
...
I have a tailwind and plugged Patterson's equations into Mathcad. His
equations verify exactly what you say below. For example, reducing the
fork offset 10% from the measured value to increase trail caused
Patterson's sensitivity measure to increase by a whopping 67%. The fork
flop nearly doubled. This is not the direction you want to go. Increasing
the trail on the Tailwind will make it unridable at low speed. The design
is already on the edge at low speed and I have the scars to prove it.


"hfhfh" wrote in message
...
I'm with you. Adding trail aids high speed stability to the detriment
of low speed stability. If you want low speed stability, lose some
trail at the possible cost of making steering twitchy at higher
speeds.

thanks guys

I changed my handlebars to a wider set yesterday and noticed an
increased
stability at low speeds today. What also seemed to help is having just
one
hand on the bars at a time. Weird


Samuel Burkeen wrote:
I have a tailwind and plugged Patterson's equations into Mathcad. His
equations verify exactly what you say below. For example, reducing the fork
offset 10% from the measured value to increase trail caused Patterson's
sensitivity measure to increase by a whopping 67%. The fork flop nearly
doubled. This is not the direction you want to go. Increasing the trail on
the Tailwind will make it unridable at low speed. The design is already on
the edge at low speed and I have the scars to prove it.


"hfhfh" wrote in message
...
I'm with you. Adding trail aids high speed stability to the detriment
of low speed stability. If you want low speed stability, lose some
trail at the possible cost of making steering twitchy at higher
speeds.

wrote in message
ups.com...
thanks guys

I changed my handlebars to a wider set yesterday and noticed an
increased
stability at low speeds today. What also seemed to help is having just
one
hand on the bars at a time. Weird

It sounds like you are tying to overcontrol the bike by using 2 hands

"Mark Leuck" wrote in message
...

wrote in message
ups.com...
thanks guys

I changed my handlebars to a wider set yesterday and noticed an
increased
stability at low speeds today. What also seemed to help is having just
one
hand on the bars at a time. Weird

It sounds like you are tying to overcontrol the bike by using 2 hands

I was thinkin the same thing. I'm surprised that I didn't figure this out
years ago.

wrote:
thanks guys

I changed my handlebars to a wider set yesterday and noticed an
increased
stability at low speeds today. What also seemed to help is having just
one
hand on the bars at a time. Weird


Handing qualities suggests that we have an anti spring at low speed. The
equation for this.

The force on the handlebar of the anti spring is

weight X B/A X trail X Sin(beta)/Rh

B is the horizontal distance from the rear wheel to the riders belly
button.

A is the wheel base

Beta is the head tube angle measured from the vertical

Rh is the radius of the handlebar.

So increasing Rh will reduce the effect of the anti spring. You did
exactly the right thing. I have seen other riders actually add a bungee
cord to act as a centering spring to overcome the anti spring.
--
Order Lords of the Chainring
http://www.calpoly.edu/~wpatters/lords.html

Or use pay pal


Reply to