Physics problem
07-09-15 | 08:23 PM
#51
Senior Member
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From: Sacramento, CA
Bikes: old ones
07-10-15 | 09:25 AM
#52
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From: Point Reyes Station, California
Bikes: Indeed!
Physics and engineering are not my strong suits so I'm afraid that, like most of the other contributors to this thread, I can offer no helpful information.
I have, however, after many decades of cycling, developed a nerve which runs directly from my ears to my hands such that any noise from the drivetrain is followed instantly by shifting to any gear that will remove the painful stimulus: Faced with your dilemma I would probably shift to a larger cog and pedal like crazy. (It is possible that physiology is also not my strong suit and that I am, once again, full of baloney.)
In my brazen youth I have been known to grind the lip off of a post CPSC Campy dérailleur in order to turn it into a pre CPSC model, for a mountain bike of all things, with TA cranks! Perhaps the preservation of rare and classic items is also not my strong suit. In fact I probably have no strong suit, but muddling along and messing with bikes is ok by me.
I have, however, after many decades of cycling, developed a nerve which runs directly from my ears to my hands such that any noise from the drivetrain is followed instantly by shifting to any gear that will remove the painful stimulus: Faced with your dilemma I would probably shift to a larger cog and pedal like crazy. (It is possible that physiology is also not my strong suit and that I am, once again, full of baloney.)
In my brazen youth I have been known to grind the lip off of a post CPSC Campy dérailleur in order to turn it into a pre CPSC model, for a mountain bike of all things, with TA cranks! Perhaps the preservation of rare and classic items is also not my strong suit. In fact I probably have no strong suit, but muddling along and messing with bikes is ok by me.
07-10-15 | 09:33 AM
#53
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Joined: Apr 2005
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From: Ann Arbor, MI
Bikes: 1980 Masi, 1984 Mondonico, 1984 Trek 610, 1980 Woodrup Giro, 2005 Mondonico Futura Leggera ELOS, 1967 PX10E, 1971 Peugeot UO-8
07-10-15 | 09:34 AM
#54
Senior Member
Joined: Apr 2005
Posts: 17,195
Likes: 761
From: Ann Arbor, MI
Bikes: 1980 Masi, 1984 Mondonico, 1984 Trek 610, 1980 Woodrup Giro, 2005 Mondonico Futura Leggera ELOS, 1967 PX10E, 1971 Peugeot UO-8
There's nothing wrong with your SR front derailleur; it's just not designed to work with pre-CPSC cranks. As I have a number of vintage cranks that need the pre-CSPC version, I'm reluctant part with any usable front derailleurs. Other front derailleurs that will work include Zeus Criterium, 1st edition Dura-Ace, SunTour Compe, SL, or 1st edition Cyclone, and Simplex Super LJ, among others.
07-10-15 | 11:51 AM
#56
Bike Butcher of Portland
Joined: Jul 2014
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From: Portland, OR
Bikes: It's complicated.
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If someone tells you that you have enough bicycles and you don't need any more, stop talking to them. You don't need that kind of negativity in your life.
If someone tells you that you have enough bicycles and you don't need any more, stop talking to them. You don't need that kind of negativity in your life.
07-10-15 | 11:52 AM
#57
Bike Butcher of Portland
Joined: Jul 2014
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From: Portland, OR
Bikes: It's complicated.
Not me, I tend to think, what will get my boss from bugging me? I've got forum posts to make, doesn't he know?
__________________
If someone tells you that you have enough bicycles and you don't need any more, stop talking to them. You don't need that kind of negativity in your life.
If someone tells you that you have enough bicycles and you don't need any more, stop talking to them. You don't need that kind of negativity in your life.
07-10-15 | 11:56 AM
#58
Bike Butcher of Portland
Joined: Jul 2014
Posts: 12,427
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From: Portland, OR
Bikes: It's complicated.
07-10-15 | 12:00 PM
#59
Bike Butcher of Portland
Joined: Jul 2014
Posts: 12,427
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From: Portland, OR
Bikes: It's complicated.
If we graph the friction caused by both methods, the force vs time graph approaches zero. To expedite matters, take a file and accelerate the break in period, and viola! No rubbing issues.
__________________
If someone tells you that you have enough bicycles and you don't need any more, stop talking to them. You don't need that kind of negativity in your life.
If someone tells you that you have enough bicycles and you don't need any more, stop talking to them. You don't need that kind of negativity in your life.
07-10-15 | 02:22 PM
#60
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As far as repairs, I just tend to grab another bike. That's one justification for having a basement full. I'll get to the Int'l at some point. However, on today's ride my Lemond was making all sorts of awful crackling noises under load. Crank arm bolts were tight as were pedals. I'm going to fire my mechanic again.
07-10-15 | 02:57 PM
#61
Bike Butcher of Portland
Joined: Jul 2014
Posts: 12,427
Likes: 7,918
From: Portland, OR
Bikes: It's complicated.
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