R
richard
Guest
I have an Independent Fabrications Crown Jewel, 55 cm, on which I
replaced the steel fork with a carbon fiber. I had reason to believe
the rake was 43 mm, so I bought a Reynolds 43 mm fork. All is well,
EXCEPT...
The past two years, decending a hill in Dubuque, IA, I have experienced
violent shimmying. The sensation is as if a REAR tire has blown and the
wheel has broken loose. The first time (last year), I nearly was lucky
to regain control in time to keep from going down along with a crowd
that no longer liked me. This year, I was ready for it...
This hill has a very smooth surface, but there is a gentle sweeping
curve. Each time, the shimmying occurred at somewhere over 35 mph.
This bike has been ridden at speeds in excess of 40 mph on other
occasions without this shimmy...
Since last year, the wheels and tires have changed. There seems to be
no play in the headset nor the hubs.
I did not experience the shimmy the year I went down this hill with the
steel fork. HOWEVER, on that occasion, it was raining and unseasonably
cold, so the hill was taken quite slowly.
Could this shimmy be the result of a fork with 43 mm rake instead of 45
mm rake? (Better yet, would the extra 2 mm solve the problem?)
Thing is, after buying and installing another fork, I'd have either a
LONG drive to Dubuque or a long wait till next year to confirm...
replaced the steel fork with a carbon fiber. I had reason to believe
the rake was 43 mm, so I bought a Reynolds 43 mm fork. All is well,
EXCEPT...
The past two years, decending a hill in Dubuque, IA, I have experienced
violent shimmying. The sensation is as if a REAR tire has blown and the
wheel has broken loose. The first time (last year), I nearly was lucky
to regain control in time to keep from going down along with a crowd
that no longer liked me. This year, I was ready for it...
This hill has a very smooth surface, but there is a gentle sweeping
curve. Each time, the shimmying occurred at somewhere over 35 mph.
This bike has been ridden at speeds in excess of 40 mph on other
occasions without this shimmy...
Since last year, the wheels and tires have changed. There seems to be
no play in the headset nor the hubs.
I did not experience the shimmy the year I went down this hill with the
steel fork. HOWEVER, on that occasion, it was raining and unseasonably
cold, so the hill was taken quite slowly.
Could this shimmy be the result of a fork with 43 mm rake instead of 45
mm rake? (Better yet, would the extra 2 mm solve the problem?)
Thing is, after buying and installing another fork, I'd have either a
LONG drive to Dubuque or a long wait till next year to confirm...