Handlebar stem for better stability; short or long?

I've recently become the proud owner of a Thorn Raven Sport Tour. Overall,
great bike.

However, initially the steering was really wobbly. I thought it was just me,
but eventually discovered the wrong forks had been fitted. Instead of a 47mm
rake, a 42mm rake fork had been fitted. It was replaced immediately.

With the 47mm rake fork it is more stable (phew!) by a factor of, say, 50%.
(I understand that this goes against conventional logic which I can't
explain!) However, how do I get to what I regard as real stability like my
current Trek 7500FX. Ravens are supposed to 'run on rails'.

The Raven comes with a number of height sizes, each of which includes a
'long' and a 'short' version. I opted for a short version because I like a
fairly upright ride, but now wonder if I would be better off with a long
version, and with a shorter handlebar stem. So the question is, would a
shorter stem (with a longer frame) provide more stability? Grateful for any
thoughts.

Also, I'm not entirely convinced by the Raven's 26" wheels. Any opinions?

PS - I've posted the same message on Bikeforums.net. Apologies if that
breaks any protocols. I'm sure someone will tell me if it has.

Best regards to all,

Frank Tompson, Bath

"Frank Tompson" wrote in message
However, initially the steering was really wobbly. I thought it was just
me, but eventually discovered the wrong forks had been fitted. Instead of
a 47mm rake, a 42mm rake fork had been fitted. It was replaced
immediately.
With the 47mm rake fork it is more stable (phew!) by a factor of, say,
50%. (I understand that this goes against conventional logic which I can't
explain!) However, how do I get to what I regard as real stability like my
current Trek 7500FX. Ravens are supposed to 'run on rails'.
Dave sez:
Hmmm, it would seem to me that a longer rake would provide LESS castor
action and stability not more. I am confused by this, is it possible it just
had WAY too much trail and was sloppy as a result? Is it possible it was
designed for larger wheels than you are running?

The Raven comes with a number of height sizes, each of which includes a
'long' and a 'short' version. I opted for a short version because I like a
fairly upright ride, but now wonder if I would be better off with a long
version, and with a shorter handlebar stem. So the question is, would a
shorter stem (with a longer frame) provide more stability? Grateful for
any thoughts.
Again Dave blathers on:
Speaking only from expierence here, I used to ride several bikes 56TT
and150mm stem. I recently switched to a 60TT and a 110 stem and a 58.5TT and
120 setm. Bear in mind that a lot of things changed in the frame design but
I kept the same bars and wheels. Also bear in mind that the chain stays are
of nearly the exact same length with a slightly longer front.

The difference is stunning. I am WAY more in control of the machine. It does
not tend to oversteer like it did and I no longer make the rear wheel jump
around if I decide to accererate in less than good road conditions. The
weight distribution is the biggest difference.

Also, I'm not entirely convinced by the Raven's 26" wheels. Any opinions?
Again Dave believes you need to read:
Frank, Can you be more specific about your lace of confidence? I have many
opinions about many things I think you mean are 26" wheels OK. Yes they
are but they cut down on your tire choices considerabley. Other than that
they don't really run any harsher or with noticably more resistance. Having
said you have fewer tire choices you should bear in mind that at least here
in the US you have more choices of tire outlets. Every Wallmart carries
these tires.

Frank Tompson, Bath

Frank Tompson wrote:
I've recently become the proud owner of a Thorn Raven Sport Tour. Overall,
great bike.

However, initially the steering was really wobbly. I thought it was just me,
but eventually discovered the wrong forks had been fitted. Instead of a 47mm
rake, a 42mm rake fork had been fitted. It was replaced immediately.

With the 47mm rake fork it is more stable (phew!) by a factor of, say, 50%.
(I understand that this goes against conventional logic which I can't
explain!) However, how do I get to what I regard as real stability like my
current Trek 7500FX. Ravens are supposed to 'run on rails'

Are you riding it laden or unladen? Is it sold as a load-carrier?

The Raven comes with a number of height sizes, each of which includes a
'long' and a 'short' version. I opted for a short version because I like a
fairly upright ride, but now wonder if I would be better off with a long
version, and with a shorter handlebar stem. So the question is, would a
shorter stem (with a longer frame) provide more stability? Grateful for any
thoughts.

My Thorn Nomad also has very floppy steering. I *think* this is because
it's designed to be ridden fully loaded, and I never have any weight on
the front. I'm used to it now, but it was a surprise the first time I
got out of the saddle and the bike headed for the ditch.

Also, I'm not entirely convinced by the Raven's 26" wheels. Any opinions?

I'm not convinced by the 26" wheels on my Nomad either. I know there's
very little difference in circumference, but the ride does seem worse on
our potholed, broken roads.

This is an interesting read:
http://www.precisiontandems.com/artbillwheelsize.htm