Help with chain tension on a single speed conversion.

"Trevor Jeffrey" writes:

Andrew Webster wrote in message
. ..

But the OP says that his chain seizes up. A better QR won't solve
that. Also, if the QR didn't slip before conversion, why should it
now?

When one is constrained to one gear, one must push harder to compensate for
the lack of availability of a lower gear. The chain pulls the hub forward
in the slots because the pulling force upon the chain is greater and so is
to overcome the friction available at the locknut.

Nice try. Thanks for playing.
The higher the gear, the less tension in the chain.
You got fooled because it is harder to pedal, but it is
easier on the chain.

Jim Smith wrote in message ...
"Trevor Jeffrey" writes:

Andrew Webster wrote in message
. ..

But the OP says that his chain seizes up. A better QR won't solve
that. Also, if the QR didn't slip before conversion, why should it
now?

When one is constrained to one gear, one must push harder to compensate
for
the lack of availability of a lower gear. The chain pulls the hub
forward
in the slots because the pulling force upon the chain is greater and so
is
to overcome the friction available at the locknut.

Nice try. Thanks for playing.
The higher the gear, the less tension in the chain.
You got fooled because it is harder to pedal, but it is
easier on the chain.

Maximum tension within the chain is determined by pedal force and front
sprocket size alone and has nothing to do with gear ratio. Acceleration is
affected by gear ratio. So for a high gear ratio the bicycle accelerates
more slowly yet the force upon the pedals is usually increased, which is why
the axle slips.

Trevor

Jim Smith wrote in message ...
"Trevor Jeffrey" writes:

Andrew Webster wrote in message
. ..

But the OP says that his chain seizes up. A better QR won't solve
that. Also, if the QR didn't slip before conversion, why should it
now?

When one is constrained to one gear, one must push harder to compensate
for
the lack of availability of a lower gear. The chain pulls the hub
forward
in the slots because the pulling force upon the chain is greater and so
is
to overcome the friction available at the locknut.

Nice try. Thanks for playing.
The higher the gear, the less tension in the chain.
You got fooled because it is harder to pedal, but it is
easier on the chain.

Maximum tension within the chain is determined by pedal force and front
sprocket size alone and has nothing to do with gear ratio. Acceleration is
affected by gear ratio. So for a high gear ratio the bicycle accelerates
more slowly yet the force upon the pedals is usually increased, which is why
the axle slips.

Trevor

Andrew Webster wrote in message

But the OP says that his chain seizes up. A better QR won't solve
that. Also, if the QR didn't slip before conversion, why should it
now?

Might be that his bike had old-style thin dropouts with a clamp on
derailer hanger. Conversions involving removal of such adaptor claws
sometimes do require shorting the protrusion of the axle on the right side.

Trevor Jeffrey wrote:

When one is constrained to one gear, one must push harder to compensate for
the lack of availability of a lower gear. The chain pulls the hub forward
in the slots because the pulling force upon the chain is greater and so is
to overcome the friction available at the locknut.

Jim Smith wrote

Nice try. Thanks for playing.
The higher the gear, the less tension in the chain.
You got fooled because it is harder to pedal, but it is
easier on the chain.

That's a bit of an oversimplification.

For a given amount of pedal force, chain tension is inversely
proportional to the size of the chainring. (Bigger chainring/higher
gear=less tension)

How ever, for a given amount of bicycle driving force at the tire, chain
tension will be inversely proportional to the size of the rear sprocket.
(Smaller sprocket/higher gear=more tension.)

Sheldon "Maths" Brown
+-------------------------------------------------+
| My mother would have been 90 years old today |
| Some of my her paintings may be seen at: |
| http://sheldonbrown.com/joyce |
+-------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

Andrew Webster wrote in message

But the OP says that his chain seizes up. A better QR won't solve
that. Also, if the QR didn't slip before conversion, why should it
now?

Might be that his bike had old-style thin dropouts with a clamp on
derailer hanger. Conversions involving removal of such adaptor claws
sometimes do require shorting the protrusion of the axle on the right side.

Trevor Jeffrey wrote:

When one is constrained to one gear, one must push harder to compensate for
the lack of availability of a lower gear. The chain pulls the hub forward
in the slots because the pulling force upon the chain is greater and so is
to overcome the friction available at the locknut.

Jim Smith wrote

Nice try. Thanks for playing.
The higher the gear, the less tension in the chain.
You got fooled because it is harder to pedal, but it is
easier on the chain.

That's a bit of an oversimplification.

For a given amount of pedal force, chain tension is inversely
proportional to the size of the chainring. (Bigger chainring/higher
gear=less tension)

How ever, for a given amount of bicycle driving force at the tire, chain
tension will be inversely proportional to the size of the rear sprocket.
(Smaller sprocket/higher gear=more tension.)

Sheldon "Maths" Brown
+-------------------------------------------------+
| My mother would have been 90 years old today |
| Some of my her paintings may be seen at: |
| http://sheldonbrown.com/joyce |
+-------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

Sheldon Brown writes:

Andrew Webster wrote in message

But the OP says that his chain seizes up. A better QR won't solve
that. Also, if the QR didn't slip before conversion, why should it
now?

Might be that his bike had old-style thin dropouts with a clamp on
derailer hanger. Conversions involving removal of such adaptor claws
sometimes do require shorting the protrusion of the axle on the right
side.

Trevor Jeffrey wrote:

When one is constrained to one gear, one must push harder to compensate for
the lack of availability of a lower gear. The chain pulls the hub forward
in the slots because the pulling force upon the chain is greater and so is
to overcome the friction available at the locknut.

Jim Smith wrote
Nice try. Thanks for playing.
The higher the gear, the less tension in the chain.
You got fooled because it is harder to pedal, but it is
easier on the chain.

That's a bit of an oversimplification.

For a given amount of pedal force, chain tension is inversely
proportional to the size of the chainring. (Bigger chainring/higher
gear=less tension)

How ever, for a given amount of bicycle driving force at the tire,
chain tension will be inversely proportional to the size of the rear
sprocket. (Smaller sprocket/higher gear=more tension.)

Yep. I was just thinking about the chainrings, forgot about the sprokets.
That'll teach me to be hasty.

Sheldon Brown writes:

Andrew Webster wrote in message

But the OP says that his chain seizes up. A better QR won't solve
that. Also, if the QR didn't slip before conversion, why should it
now?

Might be that his bike had old-style thin dropouts with a clamp on
derailer hanger. Conversions involving removal of such adaptor claws
sometimes do require shorting the protrusion of the axle on the right
side.

Trevor Jeffrey wrote:

When one is constrained to one gear, one must push harder to compensate for
the lack of availability of a lower gear. The chain pulls the hub forward
in the slots because the pulling force upon the chain is greater and so is
to overcome the friction available at the locknut.

Jim Smith wrote
Nice try. Thanks for playing.
The higher the gear, the less tension in the chain.
You got fooled because it is harder to pedal, but it is
easier on the chain.

That's a bit of an oversimplification.

For a given amount of pedal force, chain tension is inversely
proportional to the size of the chainring. (Bigger chainring/higher
gear=less tension)

How ever, for a given amount of bicycle driving force at the tire,
chain tension will be inversely proportional to the size of the rear
sprocket. (Smaller sprocket/higher gear=more tension.)

Yep. I was just thinking about the chainrings, forgot about the sprokets.
That'll teach me to be hasty.