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Singlespeed & Fixed Gear "I still feel that variable gears are only for people over forty-five. Isn't it better to triumph by the strength of your muscles than by the artifice of a derailer? We are getting soft...As for me, give me a fixed gear!"-- Henri Desgrange (31 January 1865 - 16 August 1940)

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Old 11-20-08, 09:16 PM   #1
Adam G.
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Rake distance.

When you hear someone say less rake does that mean the fork is closer to the head tube? Because the geometry on a track bike, you want the fork and wheel as close as possible the head tube for quicker reaction?
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Old 11-20-08, 09:30 PM   #2
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No, it means the fork is closer to leaves raking chain stay arch bridge.
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Old 11-20-08, 09:45 PM   #3
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I'm not certain that I understand your question but look at this and ask again...
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Old 11-21-08, 07:14 AM   #4
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Cruiser bikes will often have less rake than a track bike but it's due to their slack headtube angle. Less rake, more trail, for the same angle.

Then there's the angle of the fork blades to the steerer crown. That angle on a straight bladed fork is often the same created by a fork with curved ends. You end up with the same rake, just different looks.

So when looking for that ultra twitchy tarck bike, check out the headtube angle. The ultimate of course, being a unicycle.
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Old 11-21-08, 08:46 AM   #5
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Originally Posted by bbattle View Post
Cruiser bikes will often have less rake than a track bike but it's due to their slack headtube angle. Less rake, more trail, for the same angle.

Then there's the angle of the fork blades to the steerer crown. That angle on a straight bladed fork is often the same created by a fork with curved ends. You end up with the same rake, just different looks.

So when looking for that ultra twitchy tarck bike, check out the headtube angle. The ultimate of course, being a unicycle.
lol. what?
are you joking about this?

slack head angles usually have more rake.
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Old 11-21-08, 09:04 AM   #6
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http://davesbikeblog.blogspot.com/20...le-bit-of.html

http://davesbikeblog.blogspot.com/20...rrelly_30.html

http://en.wikipedia.org/wiki/Bicycle...cycle_geometry

In the top two diagrams of the wikipedia link, they have the same rake distance, but the left one has more trail due to the slack head tube angle.

In the bottom two diagrams, the left one has less rake offset but more trail so it's more stable and easier to ride no hands. The one on the right, with more rake offset, has less trail so will be twitchier and more responsive to ride. All of the forks in these diagrams have the same angle of the fork blades to the steerer tube.


http://www.phred.org/~josh/bike/trail.html

"Trail is the distance the contact patch of the front tire lags behind the point where the steering axis intercepts the ground.

Consider the casters on a shopping cart: the wheels are offset behind the vertical steering axis, and the force of the ground on the wheel tries to center the wheel on the direction of travel.

The greater the distance between the steering axis intercept and the contact patch, the stronger the centering force becomes.

For a given steering angle, offsetting the hub forward reduces trail, while offestting the hub backward increases trail. This may seem counterintuitive, since very stable cruiser bikes usually have more fork rake than twitchy track bikes. But the other factor at work is the angle of the steerer -- cruiser bikes have very slack head tubes, so they have more trail despite their fork rake, not because of it.
Standard road bikes have the hub offset ahead of the steering axis. This can be done several ways:

By bending the fork blades forward in a curve;
By offsetting the blades ahead of the steerer tube at the fork crown;
By offsetting the dropouts ahead of the fork blades;
By having the blades leave the fork crown at an angle to the steering axis;
or by any combination of these methods.
For a given steering angle and fork offset, the trail is the same regardless of how the offset is obtained. A straight bladed fork with 45mm of rake has exactly the same trail as a curved-bladed fork of the same length with 45mm rake. All that matters here is the points at the fork crown and the dropouts, not the shape of the fork between them. "

"He who laughs last, laughs loudest."

Last edited by bbattle; 11-21-08 at 09:08 AM.
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Old 11-21-08, 09:14 AM   #7
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Good looking, bbattle. Sums it up for me.
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Old 11-21-08, 10:16 AM   #8
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Cruiser bikes will often have less rake than a track bike but it's due to their slack headtube angle.
yeah, now read the stuff you bolded in post #6 and tell me what you think.
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Old 11-21-08, 01:49 PM   #9
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Gadzooks! I've pwned myself!!!



I meant to repeat in my first post what I copied on bold on the next post. What a jackass I was.
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