Frame "going down" when steering?
11-11-14 | 03:43 PM
#1
Thread Starter
Junior Member
Joined: Nov 2014
Posts: 5
Likes: 0
Frame "going down" when steering?
Hello,
just got an IRO Mark V frame with an ordinary 700c fork (straight arms too, but not Iro`s originaly) and i feel the frame headpart "going down" during the steering and backing up again when riding in a straight line.
thats weird, anyone experienced that or even heard about it?? its just my impression or frame geometry/fork issue?
best,
M.
just got an IRO Mark V frame with an ordinary 700c fork (straight arms too, but not Iro`s originaly) and i feel the frame headpart "going down" during the steering and backing up again when riding in a straight line.
thats weird, anyone experienced that or even heard about it?? its just my impression or frame geometry/fork issue?
best,
M.
11-11-14 | 04:22 PM
#2
Veteran Racer
Joined: Jul 2009
Posts: 11,854
Likes: 913
From: Ciudad de Vacas, Tejas
Bikes: 34 frames + 80 wheels
Sounds like a mismatch between the frame's head tube angle and the fork's offset (rake). Whether the fork legs are straight or curved doesn't matter.
11-12-14 | 08:01 AM
#4
.
Joined: Aug 2005
Posts: 12,769
Likes: 38
From: Rocket City, No'ala
Bikes: 2014 Trek Domane 5.2, 1985 Pinarello Treviso, 1990 Gardin Shred, 2006 Bianchi San Jose
Pictures of the bike would be nice. One with wheel straight, one with wheel turned to the left or right.
At first, I thought you might just have a loose headset which would give you a 'thunk' or 'clunk' sound when braking, along with some movement. But I think TejanoTrackie has called it.
check this out: Bicycle Steering Geometry
Dave Moulton's Blog - Dave Moulton's Bike Blog - Trail, fork rake, and a little bit of*history
and lots more reading here: Spectrum Cycles | Geometry
Do you feel the handling of the bike is too twitchy at low speeds? Can you ride no hands? The frame should not be moving down but may feel like it is because the wheel wants to turn so easily.
Again, pictures would be a big help. Also identify the fork; see if you find any info on it. What size frame do you have? The headtube angle changes as the frame size changes.
At first, I thought you might just have a loose headset which would give you a 'thunk' or 'clunk' sound when braking, along with some movement. But I think TejanoTrackie has called it.
check this out: Bicycle Steering Geometry
Dave Moulton's Blog - Dave Moulton's Bike Blog - Trail, fork rake, and a little bit of*history
and lots more reading here: Spectrum Cycles | Geometry
Do you feel the handling of the bike is too twitchy at low speeds? Can you ride no hands? The frame should not be moving down but may feel like it is because the wheel wants to turn so easily.
Again, pictures would be a big help. Also identify the fork; see if you find any info on it. What size frame do you have? The headtube angle changes as the frame size changes.
