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Conference noted::bicycle

Title: Bicycling
Notice:Bicycling for Fun
Moderator:JAMIN::WASSER
Created:Mon Apr 14 1986
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:3214
Total number of notes:31946

2232.0. "Shimano 105SC friction?" by SHALOT::ELLIS (John Lee Ellis - assembly required) Mon Apr 06 1992 11:20

    
    With all the talk about running STI against "mere" 7-speed freewheels,
    plus the usual Titanium-mania, the following may seem Neanderthal,
    but...
    
        My friend Pat has a Shimano 105SC drivetrain.  Since it was new,
    	it has seemed to offer resistance (friction) when cranking forwards.
        So far we still have the original set-up except that the cluster
        is now 13-28 and the chain is now a Sedisport (which helped a little).
    
        In comparing with my bikes, I have the sense that the *chainrings*
        are part of the problem.  Admittedly, the 105 chainrings and crankset
        are not aesthetically overwhelming, but the suspicion is now dawning
        that the roughness of the metal (in the chainrings) and the cut of
        their teeth add friction.  (Comparison is with Chorus, C-Record, and
        Croce d'Aune, but I also suspect Ultegra would be a lot smoother.)
    
    We've tried cleaning, adjustments, lubrication, and the friction remains.
    I'm very tempted to stick Chorus cranks (and BB) on the bike next.
    Has anyone had similar experience with 105 or other models?
    
    -john
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2232.1105SCAUDIO::MCGREALMon Apr 06 1992 12:0216
Hi,
	I have a Paramount Series 5 with the 105sc groupo. It's
	only one season old but I find it smooth and reliable.
	I've put about 1400 miles on it and have had no problems.
	This could certainly mean at least a couple of things, one is that 
	my sense of smoothness is not that acute or the problem is
	with the particular instance of your 105 but maybe not with
	all 105s and so on.
	
	Also your comparisons are with groupos costing signigicantly more
	money. I would expect them to perform a lot better.

	Sorry I can't concur with your friends problem.

	Pat 
	
2232.2Wild guesses39675::MJOHNSONMatt JohnsonMon Apr 06 1992 14:3611
    I know this sounds too simple-minded, but...
    
    o Could the chain be too tight?
    
    o What about the alignment of the chainrings with the rear cluster?
    
    o Are the bottom bracket bearings good? (Crank spins freely with no 
      chain on it?)
    
    Spinning in reverse is OK?  (You said it had trouble moving forwards.)
    
2232.3quite sensibleSHALOT::ELLISJohn Lee Ellis - assembly requiredMon Apr 06 1992 15:0427
    Matt,
    
    >    o Could the chain be too tight?
    
         Could check that - it's a possibility.
    
    >    o What about the alignment of the chainrings with the rear cluster?
    
         Looks ok - will recheck.
    
    >    o Are the bottom bracket bearings good? (Crank spins freely with no
           chain on it?)
    
         Yes, the crank spins ok without the chain.
    
    >    Spinning in reverse is OK?  (You said it had trouble moving
         forwards.)
    
         Spinning in reverse exhibits same sense of friction (in both
         directions this is by hand, not while riding - so it is a subtle
         think, I guess).  I tried "forward" to eliminate friction in the
         freehub mechanism (which in fact was doing fine).
    
    Simple minded or not, those are the only types of things that make
    sense.  :-)  I'll look further.
    
    -john
2232.4Rear Derailleur Pulleys?NEMAIL::DELORIEAI've got better things to do.Tue Apr 07 1992 12:091
How about the rear derailleur pulleys. Maybe they are not on properly...???
2232.5SHALOT::ELLISJohn Lee Ellis - assembly requiredTue Apr 07 1992 12:136
    
    RE: rear-derailleur pulleys
    
    Thanks, Tom - they looked ok from a distance, but I'll check.
    
    -john
2232.6...or change the frame?SHALOT::ELLISJohn Lee Ellis - assembly requiredMon Apr 13 1992 08:5624
    
    An update, of sorts...
    
    Pat has been trying out my blue De Rosa (SLX) the last couple
    of days (starting Wednesday for 30 miles and including a century
    yesterday).  Many of her riding difficulties have been corrected
    as a result.  She says she feels so much more confident on turns
    and above 30mph on descents that she can really ride full out,
    instead of holding back and being a nervous wreck.  Ok, this has
    nothing to do with the 105 components, but everything to do with
    the Allez geometry, as Bat Buchanan warned in these notes a year
    or two ago.  The De Rosa, though heavier, is faster ... because the
    geometry is right, and you can depend on the bike.
    
    The downside is that until Pat gets a bike of this ilk for herself,
    it looks like I've "lost" mine...  :-)
    
    Oh, for completeness, I'll still check out the Mystery of the 105. 
    
    -john
    
    PS: Her first reaction was, "This is a great *touring* bike!"
    to which our cycling companion said, "Oh yes, Eddy Merckx
    used it to great effect on several Tours ... de France."
2232.7JUNCO::HUIWed Apr 15 1992 18:028
John,

How about the Jockey Pulley bolts being too tight or pullies not greased? Also
check the rear wheel cones. Are they adjusted correctly?

Good Luck,

Dave