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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

632.0. "An Automatic Transmission!?!?" by AIMHI::SMITH (Never say never, I always say.) Mon Apr 25 1988 08:36

    
    	In their coverage of the Long Beach Bicycle Show, Mountain Bike
    	Action (May 88) had a picture, from which I couldn't make out
    	any of the details, of an automatic transmission. The caption
    	of the picture said :
    
    	For years the Browning family has been developing its automatic
    	transmission system. It's now perfected, and one of the most
    	talked about products in the cycling world. The years of hard
    	work have paid off and Browning is now the-top-of-the-line
    	choice of most builders.
    
    	Does anyone know anything about this unit? I did a dire/title=
    	"automatic" and "trans", but found nothing, which is surprising
    	for one of the most talked about products in the cycling world.
    	It sounds interesting, anyway. I wonder how well it works and
    	how much it weighs, etc.
    
    								   Mike
T.RTitleUserPersonal
Name		DateLines
632.1ElectroshiftCIMNET::MJOHNSONMatt JohnsonMon Apr 25 1988 09:3025
    I don't know if there's been further development since I saw a 
    picture of it, but Browning makes servo-shift non-derailleur
    gearing systems.  The company started by replacing the front
    derailleur/chainrings with a pair of chainrings that "hinge"
    to guide the chain onto the adjacent ring when you push the 
    shift button -- like the switches on railroad tracks.
    
    There are a couple of inherent disadvantages to this method:
    the shift occurs at the same position in the stroke, regardless
    of when you press the button (the hinge is only on one section
    of the chainring).  This means a rider might have to wait up
    to one full stroke before the shift happens.
    
    Supposedly, the company was going to do a system for the back
    gears, which looked like a much bigger challenge to me. (How
    do you shift accross multiple gears at once, for instance?)
    Maybe this is what the magazine meant by saying it had been 
    "perfected."
    
    
    MATT
    
    PS- Is it "cheating" to have electrically activated components 
        on your bike?  I think we're going to see lots more of these
        in the future....
632.2Current Browning status...JETSAM::HANAUERMike... Bicycle~to~Ice~CreamMon Apr 25 1988 13:2218
Just read an article on Browning...

It's not really an automatic transmission since you still need to
decide when to shift, and then shift it yourself.  In an automatic
transmission, shifting is an invisible need like on a car or a
camera with autofocus or autoexposure.  Maybe "semi-automatic"? 

Browning does have a rear wheel system at prototype stage.  It
apparently only does three cogs (rather than the usual 5, 6 or 7).
Browning claims that three is enough because, on a bike so equipped
on the front and rear, double (simultaneous front and rear) shifting
is easy. 

Personally, i'll reserve judgement on this.  Maybe 3 cogs is just 
for now, and they will later increase it with further development, 
don't really know.

	~Mike
632.3A real automaticULTRA::WITTENBERGSecure Systems for Insecure PeopleTue Apr 26 1988 14:516
    I saw  an ad for a automatic transmission that measures tension on
    the  chain  and  shifts  the  rear derailleur to keep that tension
    within the set range. It weigs "less than a pound". It didn't seem
    like anything I wanted so I don't have any more details.

--David
632.4Recent DevelopmentsSTAR::TEAGUEI'm not a doctor,but I play one on TV...Thu May 05 1988 12:3617
It's true, the Browning Automatic Transmission isn't automatic in the 
sense that a car's automatic transmission is.  It's basically an 
electrically-powered front derailleur.  And up until very recently, it
was at least being offered as an option on some top of the line mountain
bikes.

Not anymore, however.  Suntour has just acquired exclusive rights to 
market and sell the unit, and has put orders on hold.  I was told that
there weren't serious problems with it or anything, but that Suntour was
making the unit more robust (i.e., more waterproof, etc.).

Re: cheating.  Interesting philosophical question.  Did any of us accuse
indexed shifting of that a couple of years ago???

.jim