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Rans V2 Formula?



 
 
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  #21  
Old July 18th 03, 03:59 PM
Steve Christensen
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Default Rans V2 Formula?

In article ,
says...

Steve Christensen wrote in message
...
luvabluzer wrote:


Steve,

You got a custom V2 with similar components except for the aluminum
frame for $1800? That's what I paid for my stock V2 back in 2001.



Seemed like a good deal to me too. The only differences are the steel frame and
the standard seat.


Steve Christensen



Keep in mind though, that the aluminum framed version weights about 7
pounds less than the cromo version (with upgraded components too).
That is a sigificant amount of weight on a bike. Also, aluminum is
less flexy which should provide more speed. A good example of this is
the tour easy (cromoly)vs the gold rush (aluminum). They are very
different performing bikes.
Marci



Well according to their site the weight difference is 5 lbs for the Formula,
which is, I grant you, significant. I'll have to get around to weighing my
custom V2 to see how much more it weighs with the standard seat and frame. I'm
guessing it will be 2 to 3 lbs heavier than the Formula. (Which would work out
to $400 to $600 a pound for the difference.)

As for the aluminum frame and the Gold Rush comparison, with the standard V2 and
Formula there is more than just the frame that is different, and I suspect that
it is the same with the Gold Rush. Meaning you can't contribute all of the
performance difference to the frame, as the upgraded bike usually has better
wheels and components.

I wonder about the importance of frame stiffness too. There have been a number
of interesting comments recently on the value of rigid pan type seats. One of
the advantages is said to be that the seat does not flex, so that all of your
energy goes into the bike. This makes me wonder whether improving the stiffness
of the frame is as meaningful if you don't have a rigid seat to transfer the
energy without power loss.

Anyway I'll have to get out the scale.

Steve Christensen

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  #22  
Old July 18th 03, 06:39 PM
Marci Taylor
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Default Rans V2 Formula?

Tom Sherman wrote in message ...
Marci Taylor wrote:
...Also, aluminum is
less flexy which should provide more speed. A good example of this is
the tour easy (cromoly)vs the gold rush (aluminum). They are very
different performing bikes.


The aluminium alloy frame will be stiffer than the steel only if tubing
with a significantly higher moment of inertia (larger diameter and/or
greater wall thickness) is used. Aluminium alloys typically have an
elastic modulus in the range of 70-80 GPa, while the elastic modulus of
steel is around 200 GPa. So a steel tube will be almost three times as
stiff as an aluminium alloy tube of the same diameter and wall
thickness.

Tom Sherman - Quad Cities USA (Illinois side)


Hi Tom:
That is interesting. Obviously you have some good knowledge on this
as I do not. I am wondering though, why then the tour easy is
reported to be much slower than the GRR with same component package.
Bob Bryant of RCN news reports MUCH greater speeds on the GRR than the
Tour EAsy with same conditions/rider/etc. What do you think? Also,
Bob Bryant, if you are reading this, maybe you could comment.
Marci
  #23  
Old July 18th 03, 06:39 PM
Marci Taylor
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Posts: n/a
Default Rans V2 Formula?

Tom Sherman wrote in message ...
Marci Taylor wrote:
...Also, aluminum is
less flexy which should provide more speed. A good example of this is
the tour easy (cromoly)vs the gold rush (aluminum). They are very
different performing bikes.


The aluminium alloy frame will be stiffer than the steel only if tubing
with a significantly higher moment of inertia (larger diameter and/or
greater wall thickness) is used. Aluminium alloys typically have an
elastic modulus in the range of 70-80 GPa, while the elastic modulus of
steel is around 200 GPa. So a steel tube will be almost three times as
stiff as an aluminium alloy tube of the same diameter and wall
thickness.

Tom Sherman - Quad Cities USA (Illinois side)


Hi Tom:
That is interesting. Obviously you have some good knowledge on this
as I do not. I am wondering though, why then the tour easy is
reported to be much slower than the GRR with same component package.
Bob Bryant of RCN news reports MUCH greater speeds on the GRR than the
Tour EAsy with same conditions/rider/etc. What do you think? Also,
Bob Bryant, if you are reading this, maybe you could comment.
Marci
  #24  
Old July 19th 03, 12:13 AM
stratrider
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Default Rans V2 Formula?

Tom, can we as readers (and riders) then conclude that the tubing used
on the GRR must have thicker walls than the TE (as I see no difference
in tubing diameter)?

Jim Reilly
  #25  
Old July 19th 03, 12:13 AM
stratrider
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Default Rans V2 Formula?

Tom, can we as readers (and riders) then conclude that the tubing used
on the GRR must have thicker walls than the TE (as I see no difference
in tubing diameter)?

Jim Reilly
  #28  
Old July 19th 03, 01:53 AM
Tom Sherman
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Default Rans V2 Formula?


stratrider wrote:

Tom, can we as readers (and riders) then conclude that the tubing used
on the GRR must have thicker walls than the TE (as I see no difference
in tubing diameter)?


I recall the GRR as having larger diameter tubing than the TE - would
someone from Easy Racers or a dealer inform us of the actual tubing
diameters (and wall thicknesses if available).

Tom Sherman - Quad Cities USA (Illinois side)
  #29  
Old July 19th 03, 01:53 AM
Tom Sherman
external usenet poster
 
Posts: n/a
Default Rans V2 Formula?


stratrider wrote:

Tom, can we as readers (and riders) then conclude that the tubing used
on the GRR must have thicker walls than the TE (as I see no difference
in tubing diameter)?


I recall the GRR as having larger diameter tubing than the TE - would
someone from Easy Racers or a dealer inform us of the actual tubing
diameters (and wall thicknesses if available).

Tom Sherman - Quad Cities USA (Illinois side)
 




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